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Is it possible to move your arms above your head when handcuffed in the back?
This move was seen in Pitch Black and i wonder if it is possible at all. Say you are handcuffed to a pole, hands in the back, and the pôle is a little higher than your head. You just want to do a complete loop with your hands, going above your head, so they end up in front of you and you are free of the pole.
Now, putting horrible pain aside, is it possible to perform this move alone?
If not, maybe with a small surface to rely on, for a lever effect?
Would it cause minor / major damage at all or just pain ?
I am also curious if performing this move slightly turned sideways help ( as much as you could at least, considering the situation). In the movie he goes one shoulder at a time.
Anyway, i hope im clear enough !
Exactly what i mean is this video at 1:35

Contortionists do far more painful looking stuff, so I guess with the right training it could be possible.

Sort of like http://youtu.be/lY5V5la5nhU, https://www.youtube.com/watch?v=5bJyXN9EBrk or http://youtu.be/RpV4FHyQTyc?
Depends on the hight of the pole though.

Thanks everyone !
I just saw someone wrote an amazing answer that i was about to validate, but then deleted it. :(

I edited my answer with an exact video if what i saw.

Another very clear example https://www.youtube.com/watch?v=fRcuoLSDTjM, and a contortionist like this: http://youtu.be/sPYU24bauOM could do it without any problems.

yeah my sister can do it and she never said it was painful :P

i can do it. i can put my hands behind my back than over my head many times before. even with handcuffs, i tested myself.

maybe if you can, step through the handcuffs and then it'd also be in front. it's not easy or for everyone, I'll grant you, but it's possible for some

This is not normally possible or would be extremely painful if done. But there are special cases.

Atraumatic dislocation.
  This occurs when the shoulder dislocates with minimal force such as reaching up for an object or turning over in bed. Usually it will 'pop' back in itself or with a little help. Normally this type of dislocation does not need reducing in A&E. It can occur regularly throughout the day and will be associated with certain positions the arm is placed into. This type of dislocation is associated with people that have 'lax' joints, for example people who hyper-extend their knees and elbows and can get the palms of both hands onto the floor with ease.  This joint laxity is normal for these people and the onset of dislocation can be associated with a change in how the muscles around the shoulder are interacting with each other or a change in posture/ position of the arm. This can produce an imbalance in the control of the joint. Referral for appropriate physiotherapy is the initial form of management. The physiotherapist should look at the way in which the muscles and shoulder joint is moving and posture aiming to restore the balance. Treatment can 'cure' the problem as long as the exercises and advice is continued, but in some cases there is only minimal or nil benefit. At this point surgical intervention is indicated.
Positional Non-traumatic dislocations.
  This group of people can dislocate their shoulders without any form or history of trauma. Some may have started out dislocating their shoulder as a party trick; others may have always had shoulders that just 'fall' out of joint. This type of dislocation is usually painless and can be put back in easily. Both shoulders are typically involved. The cause of this type of dislocation is usually a result of what we call 'abnormal muscle patterning' which means the strong muscles around the shoulder joint are not working in the correct order causing them to pull the shoulder out of joint with active movement in the particular direction such as lifting the arm forward above the head or out to the side and above the head.  The main treatment for this is physiotherapy that looks at re-sequencing the muscles in order to prevent further dislocations.  Occasionaly surgery in the form of thermal capsular shrinkage or plication may be neccessary.

Taken from here such people would be able to dislocate then get their hands in front and relocate.
The body can be trained to be quite flexible through training like gymnastics etc...

Depending on the situation (i.e. orientation/rigidity of cuffed hands and the height of the pole), you could potentially escape, but getting your arms flipped around where your hands are in front of you would involve serious damage.
It may be technically possible to achieve alone with some way to continue wedge your arms further, but the pain would probably knock you out before you succeeded.

I thought so, too; see @fileunderwater's YouTube link.


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Difference between pulse and blood pressure
I'm a very naive and biologically illiterate person, and from what I've read on the internet I'm not really sure I understand the difference between pulse and blood pressure. I'm guessing for most of you this is trivial so I'm hoping for something clear for someone of my "level".
On a side note, I speak french, and we have two words: pression / tension (artérielle). One of them must be wrong since they mean totally different things and makes things even more confusing.
But from what I could gather, are the next statements correct/accurate or am I completely off?

The blood pressure is the fluid's movement "strength" in the veins (or "arteries", please edit my post with the correct english word)
The "tension" is the force applied on the veins itself, kind of like when you're pulling a rubber band
The pulse is just the wave of blood moving, which creates different tensions over the vein and whose movement is created by the pressure.

The blood pressure is the fluid's movement "strength" in the
  arteries (or "artères", please edit my post with the correct english word)

Blood pressure is a measurement of the strength of flow through the arteries. (I.e., the force per unit area exerted by the blood on arterial walls.) So replace vein with artery and your definition is correct.

The "tension" is the force applied on the veins itself, kind of like
  when you're pulling a rubber band

In cardiovascular terminology, hypertension and hypotension are used interchangeably with high and low blood pressure (even though technically tension uses force units and pressure uses force/unit area units). Your definition sounds more like arterial tensile strength, which is the ability of the artery to withstand pulling forces without breaking (which decreases with age).

The pulse is just the wave of blood moving, which creates different
  tensions over the vein and whose movement is created by the pressure.

Pulse is an indirect measurement of heart rate. So, yes, it's the rate of the "wave of blood moving." It creates different "pressures" measured by systolic (the "wave" in your terms) and diastolic (the "trough") whose movement is created by the force (of the heart walls contracting).

There are many articles on pulse and blood pressure, but here's an analogy:
Think of the blood as a heavy iron block you are trying to move by hitting it with a sledgehammer.  Blood pressure is how hard you hit with the hammer.  Pulse (heart rate) is how often you hit with the hammer.
This analogy can be taken further if you like:  There is also stroke volume which is how far the block moves each time you hit it with the hammer, and cardiac output, which is how fast the block moves on average as you hit it with a hammer (depending on the pulse and stroke volume).  Vascular resistance is the friction on the block that makes it hard to move (demanding more blood pressure...)

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Are there official criteria for an experiment to be considered statistically robust for publication in a decent scientific journal?
For a high school project, I investigated the effect of breathing meditation on teenagers. 15 students were asked to follow specific directions and meditate for 10 minutes a day for 8 weeks. Each week, their heart rate, ventilation rate, maximum lung capacity and blood pressure were measured with 5 trials. These measurements were also done prior to the meditation regimen.
My question is, to publish an experiment in a scientific paper, must there be a specific number of participants, trials, or time-length of the experiment?
This is to talk about in the discussion part of my report.
Please let me know what you know!

Based on the complaints that have been made on my questions, this question might get attacked as being off topic.

@DanielGoldman — "attacked"? I think you should choose your words a little more carefully. The SE system allows users with a certain ‘reputation’ to review questions and vote to close them if they are regard them as off-topic in the terms defined by SE Biology. This is not ‘attacking’ but is performing a public duty to help maintain the standards of the site (you can get badges for it). So, yes, I do consider this probably off topic, but no, I haven‘t voted to close as I thought it wouldn‘t hurt for someone to answer this young person.

one important thing to consider would be to compute the statistical power of your experiment. There are online calculators, e.g. here, but it does sometimes take some creativity/adjustment to match your experimental design with the numbers the calculator is expecting. The most important thing is that you need to pick an effect size that you are expecting. (This is arguably more of a statistical question, e.g. for Cross Validated rather than Biology SE)

There is no single measure for "robustness" and a lot of it boils down to the field. Usually physics has a very high degree of precision: p value close to 0. For instance, the Higgs boson was a confidence level of 5 sigma, while biology or psychology is going to usually have more leeway: maybe 2 sigma (Sigma).
However, there should be no (statistical significance) criterion to publish. The idea that only positive studies should be published has led to biases in available data in a number of fields (Fighting publication bias: introducing the Negative Results section). Negative results are very useful to us as robustness of a theory is often evaluated using meta-analyses. If a person fails to publish their results because it does not robustly justify their theory, then the data available to perform a meta-analysis is diminished.
Clearly, you want the study to be properly run and you want the method to be reasonable. A garbage study, regardless of the statistical significance measured, is going to be looked upon negatively.
That being said, if your topic is something that has been researched a number of times, a small study is not going to be looked at very well, as there is already "better" information available. The study should provide some kind of new insight into the topic.

“p values close to 1”? I think there is at least a 0.00 missing from your answer.

Yeah; should be really close to 0, not 1. Sorry. Corrected.

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Recession of skin tan
In early October I was on a holiday near the equator and got tanned. Now, roughly 3 months later, the tan on my face and arms has gone almost entirely where my belly, chest and legs are still moderately tanned. It seems that body parts that are exposed (to light) more than others seem to loose the tanning effect more quickly. Why is this? Or is there another reason?
I am not a biologist so I would appreciate an answer that is articulated in a way non-biologists can understand it.


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Recommended reading to quickly get up to speed on infectious diseases
I am in the beginning stages of a capstone project for my master's in Data Science. For various reasons, I have landed on the subject of Clostridium difficile infection. My background is in Computer Science, Mathematics, and Statistics, but biology is way outside of my wheelhouse. While most of my project will focus on the statistical modelling aspect, I would like to be able to speak intelligently on the subject itself and be able to read through journal articles without getting tripped up on some of the terminology.
I'm not trying to cut corners, but I'm on a tight timeline (about 4 months). What resources - books, references, online courses - would you recommend to bootstrap me into the field of infectious diseases?

Welcome to Biology.SE! Is it an intro book to epidemiology that you're looking for?

I think that could be helpful. Something to get me started with basic concepts or to use as a reference maybe.

Since I didn't get an answer, I'll mention what I did.
My goal was to understand a particular disease well enough to talk intelligently about it while focusing mostly on the statistics. So learning Epidemiology from the ground up wouldn't have been practical in the 4-5 months I had.
I started with a high level patient-oriented book, C. diff in 30 Minutes. That gave me a general understanding of the disease. Then I began reading academic articles. Not only were these useful for citations in my paper, but it also helped expand my understanding. I would notice common terms that kept popping up. Gram-positive, rod shaped, anaerobic, endospore-forming is intimidating at first, but each of these modifiers can be googled individually to build an understanding.
Finally, it was necessary to know how much I needed to know. I began reading about the hypervirulent strain, ribotype 027 with its binary toxin yadda yadda. None of that was actually important for my paper because that level of detail wasn't in the data.
So while knowing the general landscape was important, knowing each and every detail, for my purposes, wasn't.

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Do You Need Vitamin B12 To Utilize Folate
Just wondering if Vitamin B12 is necessary for the body to utitlize folate. My husband is on Methotrexate for rheumatoid arthritis, a medicine which is known to destroy folate. The doctors therefore prescribe high dose folic acid. He also, however, has a geographic tongue which is supposedly due to B12 defiency. If he is deficient in B12, and yet if B12 is necessary for folate absorption, the extra folic acid is presumably doing no good. Whether the two vitamins are essential co-factors is interesting to know because I've just read that folic acid deficiency gives people a 69% higher risk of heart disease. And he's just had a massive heart attack.
I can't seem to find the answer on standard search engines, would be grateful to know whether B12 is needed to utilize folate. Many thanks.

From Wikipedia: "In the form of a series of tetrahydrofolate (THF) compounds, folate derivatives are substrates in a number of single-carbon-transfer reactions, [...] It is a substrate for an important reaction that involves vitamin B12 and it is necessary for the synthesis of DNA, ...".

B12 deficiency is not the cause of benign migratory glossitis. It is the cause of pernicious anemia, though.

B12 is not necessary to utilize folate but it is necessary to replace B12 before repleting folate as otherwise you can induce subacute combined degeneration of the cord.  There are multiple mechanisms of folate absorption from the small bowel and large bowel which don't require B12.
Geographic tongue is not caused by B12 deficiency, and the actual cause is not known.  It does cause raw beef tongue.
You don't normally need to prescribe mega doses of folic acid with methotrexate.  Common doses are 5 mg per week, and 0.8 mg daily, though some physicians don't bother using folic acid at all.  Although folic acid was commonly prescribed because it was believed that methotrexate works by virtue of its ability to antagonize folic acid, it is now known that this is not true. It works as an adenosine antagonist, and so you can take the folic acid on the same day as the methotrexate if you wish.


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Would salt cause a pistachio nut not to be able to germinate?
If I buy a bag of pistachio nuts that have been hand picked off the tree when ripe, then salted in a (light) saltwater solution, then vacuum-sealed, and stored in a refrigerator, then will they germinate if I take them out and soak them in a moistened towel laying out in the sun?

Aren't commercial pistachios roasted?

These aren't commercial. They've been hand picked as described.

This article https://wikifarmer.com/how-to-grow-pistachio-tree-from-nut/
says unsalted.  Lots more on that site about growing them.


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Assays for detecting RNA binding with protein
In a project I'm working on, we are designing a system where specific RNAs bind to proteins - an important part of this is to test whether the RNA binds when we modify the proteins in some way. What assays are there to test whether a specific (or non-specific) RNA is binding to a protein?

I would reccomend an electrophoretic mobility shift assay (EMSA), one procedure for which can be found here.


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Resources to study the cell as a "mechanism"
I am looking resources that effectively describe the cell as a mechanism. The cell might be irreducibly complex, but the individual components must necessarily have simple functions, locks, keys, switches, gears, membranes, and extruders. Is there any resource that exists that classifies the great many substances in the cell in this manner?

The basic cell biology textbook does explain different parts of the cell. Can you please clarify your question?

The cell is not "irreducibly complex" at all. What makes you think it is? As @WYSIWYG suggested, you should read up on the field of "Cell Biology".


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Have there been any measurements on the genomic differences between cancer cell DNA and healthy cell DNA?
I'm loooking for simple stats like the average number of base pair differences to normal cells, average diversity between different cancer cells, etc.

Check out dcc.icgc.org, a data portal dealing with what you describe.

Yes, there are two genome projects, which aim to identify the critical mutations (and by looking for them, they discover all the mutations in a given cancer) by sequencing DNA from the cancer cells and healthy cells from the same patient.
These are "The Cancer Genome Atlas" (TCGA) and "The Cancer Genome Project (TCGP)". Both project publish their complete data and ways to browse them. The data from the TCGP can be found in the "Catalogue of somatic mutations in cancer" (COSMIC), the data from the TCGA on their project site.


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Genes where both a disabling mutation and copy number amplification cause different genetic diseases
I'm trying to make a list of such  genes, because they must be tightly regulated. MeCP2 is one - it causes Rett Syndrome with a disabling mutation, but causes MeCP2 duplication syndrome if its copy number has been increased. Anyone know of any others?

Must this list include only genes where both deletion and duplication have been shown to have disease phenotypes?  Can this list also include transcripts with dose-dependent pathologies?  i.e. genes for which deviations (both up- and down-regulation) from median expression are deleterious?

@Dirigible yes I think that would be interesting to know as well.


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Are there examples of non-pathogenic RNA viruses?
There do seem to be some non-pathogenic DNA viruses, for example Foamy virus. Non-pathogenic viruses would be great to use for gene therapy applications, except DNA viruses incorporate themselves into the genome, which could drive oncogenesis. RNA viruses that are non-pathogenic would be great, but all RNA viruses seem to be especially pathogenic. Rabies, Ebola, Bas-Congo, Smallpox, etc.
Do there exist "gentle" RNA viruses?

Does it count if their pathogenicity is species specific?

The alphaviruses typically move between an arthropod host and a mammalian host. In the arthropod, they seem to be harmless. In the mammal, they are pathogenic. If there were some way to make them treat mammalian cells like insect cells, they would be very useful for gene therapy applications.


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Why don't rates of cancer increase generation to generation?
As cells divide, they accumulate mutations that can sometimes cause cancer. Gametes have to divide like any other cell, and thus generation to generation mutations should accumulate in people's genomes. However, it doesn't appear to be the case that cancer rates increase as a species ages. Why isn't this the case? Is the process of development itself a filter that ensures that most of the cells in the body are "far from cancer"?

If an organism grew from a mutated gamete, they will carry that mutation. And if the mutation is sufficiently debilitating, they won't properly develop or survive as well as other non-mutated members of the species. So the mutation would, in theory, be filtered out by natural selection.

This Wikipedia page is relevant. Individuals can inherit germline mutated forms of the TP53 gene and have a higher cancer risk. But organisms with a high cancer risk are less viable than those with a low cancer risk so their form of the gene is filtered out.

@Jam presumably this selection pressure will decrease as medical treatments become better - so we would see cancer rates increasing for younger patients in the future?

I see what you're suggesting but I don't really know. In theory, you might be right but I think the incidence rate of the mutation would need to stay constant, and the cancer would need to affect people early enough to not affect whether they can have children.

Species age

However, it doesn't appear to be the case that cancer rates increase as a species ages

Species don't have an age. All lineages on earth are about 3.5 billions years old. No, lineage is younger or older than that. A lineage does not get its genetics magically reset when the lineage gets a new species name. For more information about the standard misunderstandings about the concept of species, please have a look at the post How could humans have interbred with Neanderthals if we're a different species?
In all cases, there is some equilibrium between the selection pressures brought about mutations that are linked to cancer (whether mutations on oncogenes or on tumor suppressor genes).
Individual age
Individual, do have an age though. Cells, within multicellular individual replicate in order to ensure the multicellular individual growth and maintenance. Those cell lineage can accumulate mutations that could be linked to cancer development. Within the individual, these mutations are not deleterious and are therefore not selected against. Actually, in case of a cancer, those mutations are, by definition, beneficial as cancerous cells proliferate (have a large fitness). As a result one should expect that old organisms are at greater risk of developing cancer than younger organisms. In humans, this correlation exists, however, the statistics are slightly more complex than that. Typically, different types of cancer seem to show different age associations. See this article from the NIH as a start for more information.

I understand that species don't age, my question is "why don't they age? why haven't all species gone extinct from cancer?"

@Mike Flynn: Basically, because the individuals carrying the cancer-causing mutation die before they can reproduce, and thus pass the mutation to their offspring.  A current example is the Tasmanian Devil, which seems likely to be rendered extinct by a particular cancer to which they're subject.

@MikeFlynn Is your question something like "How does selection gets rid of deleterious mutations?", then?


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NCBI blast for exact match of short sequence
I'm trying to Blast for exact matches to the sequence: 'ATTGNNNNGCAAACCA' in the human transcriptome using NCBI Blast on its 'refseq_rna' database. However, when I do a basic query I get "No significant similarity found."
Note the N's in the middle of the sequence, if I get rid of those N's, yielding the sequence 'AGCGGATTGCAAAGCAAACCA', I get a match in the 3' UTR of the human MeCP2 gene (which is correct). I don't understand why adding the N's here make it not work.
I looked at the help section and I believe this may be due to shorter sequences being less "statistically significant". Statistical significance of output is completely irrelevant to me, so I set 'Expect Value' to 100000000000000. However, I still get the same result.
I also tried to modify the HTML of the page to allow me to submit a word size of 4 to the form. This went through, but I still got "No significant similarity found".
Could someone help me out with this? I feel like searching for a short sequence shouldn't be this hard.

You are asking a question about a piece of software which is extremely well documented. What does the documentation say about searches with wild cards?

it says absolutely nothing

Well you might email their help desk. They are quite good about replying to queries in my experience, although my own have been of a different sort.

The second sequence is not the first sequence with the N's removed, should it be?

no it's with the N's replaced with 4 bases to make it the MeCP2 sequence

This was answered in the bioinformatics StackExchange: https://bioinformatics.stackexchange.com/questions/14423/ncbi-blast-for-exact-match-of-a-short-sequence

@MikeFlynn Please tell Maximilian Press that 4^4 = 256

You don't usually use BLAST for exact matches. I would rather suggest that you simply do a regex match using any programming language you like. Since this question has already been answered in [bioinformatics.se], I won't elaborate further.

I’m voting to close this question because it is cross posted (and answered) in [bioinformatics.se]. (https://bioinformatics.stackexchange.com/questions/14423/ncbi-blast-for-exact-match-of-a-short-sequence)


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What is the use of ampulla in Scoliodon?
What exactly is the use of Ampulla of Lorenzi in Scolidon?
It posseses eyes for seeing prey, so what is the use of Ampulla?

Welcome to Biology.SE! What research have you done before asking it here?

I am just a student of class 12 and this question is very much important for my knowledge.

very frankly, being a student of class 12 does not give you liberty to ask here questions lacking prior research effort. The question might be important, and interesting as well, but as long as you don't show an attempt to answer it yourself, we are not willing to help you out. You need to, at least, google about it and then tell us what you have found so far, and how that does not help you :)

Ok ok , thanks for giving me the exact procedure of asking questions. I'll try to work on this topic in google.

@Abhijit Have you checked Wikipedia? It says quite a lot of stuff, which should probably be enough for a 12th grader (no school is going to make you right a thesis or something on this topic).


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Ornithology related areas in Biology
In relation to my work, I'm looking at ornithology as a field, and it would be interesting for me to know which areas in biology relate to ornithology.
Any help is much appreciated!

Paleontology has paleo-ornithology as well, in fact dinosaur paleontology is very closely related.

First of all, you can look at the papers published in the Journal of the Avian Biology, the Journal of Ornithology and the Auk. There you can see how bright is the field. It is about conservation biology, distribution of species, ecology of species, behavior, migration etc.

An easy way to figure that out is to look at what ornithologists are actually doing.  If you look up the staff page for an ornithological institute, you'll be able to see what type of projects they're involved in.
Here is an example:  Percy FitzPatrick Institute of African Ornithology staff page


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How does hypochlorous acid inactivate viruses?
I was reading how bleach was used very widely as a disinfecting agent during the 2014 West Africa ebola outbreak and am interested in the mechanisms with which hypochlorous acid inactivates viruses. Most of the studies I could find only focused on its activity against bacteria. I know viruses tend to be much more difficult to inactivate than cells as they're somewhat simpler and aren't really alive.

The other answer by @CMosychuk talks about the general aspect related to use of hypochlorous acid. I will discuss here its molecular mechanism of action.
Hypochlorous acid (HOCl) is a very powerful oxidizing agent. In aqueous solution, it dissociates into H+ and OCl- as:
$$\ce{HOCl \leftrightharpoons H^+ + OCl^-}$$
However, HOCl also destroys viruses by chlorination. It acts on anything, from lipids to nucleic acids. For example, Hawkins et al ,2002 describe in detail the effects of HOCl on nucleic acids. HOCl, by direct chlorination, leads to the formation of chloramines, and ultimately nitrogen-centered radicals. These radicals often react with each other to form dimers. Also, they have reported formation of single- as well as double-stranded breaks on application of HOCl on plasmid DNA. See this image:

These reactions render the nucleic acid useless and the virus harmless. In a similar manner, HOCl also reacts with polypeptides, ultimately leading to their fragmentation. See these images (from here):

Also, as mentioned in the other answer, application of HOCl has been shown to promote denaturation and aggregation of proteins. The linked paper also talks about HOCl's effects on other biomolecules, such as carbohydrates, but those effects would be out of scope here.

This one should be the accepted answer.

@ronisaiba haha thanks for appreciation! Its totally OP's choice which answer to select, and its all right if no answer is selected. After all, both answers are great in themselves, and selecting one answer should not mean that the second answer is useless :)

A 2008 paper in Cell elucidated a mechanism not far off from how heat-denatured proteins in a cooked egg aggregate, and never return to their native conformation (1).
Remember that proteins don't do their job outside of their native conformation. The hypochlorous acid post-translationally modifies the proteins in a way that they lose their shape and begin to aggregate. The authors believe that the reactions are sufficiently fast that the denatured product builds up faster than the refolding reaction can take place. Your innate immune cells do something similar to combat microbes or cells they recognize as distressed or foreign, known as oxidative burst, by releasing compounds such as hypochlorous acid.
Now, viruses are just protein coats and nucleic acid. Sometimes they have an envelope, but the envelope is typically quite easy to destroy with detergent. Naked viruses are known to be able to survive a number of days in harsh conditions. The virus depends on elements of the protein coat such as spikes to attach and facilitate entry into the host. Denaturing agents will act to destroy these structures, preventing infection.
So what are some important considerations?
1) Concentration: At an inappropiate concentration, common disinfectants will fail because they lose efficacy. For example, alcohols at least 65-70% abv are known to be the lowest efficacious concentration, and anything lower you see the killing begin to drop off. People tend to use bleach at 10% or 100ppm I believe.
2) Contact time: Proteins take time to denature and immediately cleaning away the bleach will not accomplish your goal. Five to ten minutes wet contact time is appropriate for bleach. If it dries it loses effectiveness. Anything higher you don't see an increase in effect, either.
3) Compound: Bleach isnt good for everything. It works on hard, non-porous surfaces, but it also requires pre-cleaning because without a detergent, bleach won't remove grime or films that may inhibit its action.

Wow, I didn't even notice that you were also writing an answer :P Anyways, +1!

Ah, can you see that sort of stuff? Thanks!


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What's the benefit of the average human body temperature?
Why would the body choose a resting temperature of 36.1c to 37.2c? It seems a very inefficient mechanism of survival considering the typical ambient temperatures on Earth. If there is a benefit to needing to continuously do extra work, what is it?

what have you searched so far to answer this?

What's the benefit of the average human body temperature?

It's a balance between preventing infection and not requiring excessive food intake. It is has also been claimed that this is the temperature at which the most essential enzymes are most reactive, without becoming damaged by excess temperature.
References:

"Mammalian Endothermy Optimally Restricts Fungi and Metabolic Costs", by Aviv Bergman and Arturo Casadevall, DOI: https://doi.org/10.1128/mBio.00212-10
"Fungal virulence, vertebrate endothermy, and dinosaur extinction: is there a connection?" (.PDF), by Arturo Casadevall, DOI: https://doi.org/10.1016/j.fgb.2004.11.008

"The number of fungal species that can thrive and therefore infect an animal declines by 6 percent for every 1° C rise in temperature. This means that tens of thousands of fungal species infect reptiles, amphibians and other cold-blooded animals, but only a few hundred harm mammals.".

It is useful to refer to ectotherms (an organism in which internal physiological sources of heat are of negligible importance in controlling body temperature, which permits them to operate at very economical metabolic rates) as poikilotherms when applicable.

"Poikilothermic animals include types of vertebrate animals, specifically some fish, amphibians, and reptiles, as well as a large number of invertebrate animals. The naked mole-rat is the only mammal that is currently thought to be poikilothermic.".
"Poikilotherm animals must be able to function over a wider range of temperatures than homeotherms. The speed of most chemical reactions vary with temperature, and in order to function poikilotherms may have four to ten enzyme systems that operate at different temperatures for an important chemical reaction. As a result, poikilotherms often have larger, more complex genomes than homeotherms in the same ecological niche. Frogs are a notable example of this effect, though their complex development is also an important factor in their large genome.
Because their metabolism is variable and generally below that of homeothermic animals, sustained high-energy activities like powered flight in large animals or maintaining a large brain is generally beyond poikilotherm animals. The metabolism of poikilotherms favors strategies such as sit-and-wait hunting over chasing prey for larger animals with high movement cost. As they do not use their metabolisms to heat or cool themselves, total energy requirement over time is low. For the same body weight, poikilotherms need only 5 to 10% of the energy of homeotherms.".

This update speaks to the theories on enzymes (solitary from metabolism), offered in other answers.
Articles and theories that are not discredited:

Enzyme assays by Hans Bisswanger:
That article is mostly concerned with the temperature used to conduct assays of enzymes.

"The essential requirements for enzyme assays are described and frequently occurring errors and pitfalls as well as their avoidance are discussed. The main factors, which must be considered for assaying enzymes, are temperature, pH, ionic strength and the proper concentrations of the essential components like substrates and enzymes. Standardization of these parameters would be desirable, but the diversity of the features of different enzymes prevents unification of assay conditions. Nevertheless, many enzymes, especially those from mammalian sources, possess a pH optimum near the physiological pH of 7.5, and the body temperature of about 37 °C can serve as assay temperature, although because of experimental reasons frequently 25 °C is preferred. But in many cases the particular features of the individual enzyme dictate special assay conditions, which can deviate considerably from recommended conditions.".
...
"Enzymes display their highest activity at their respective optimum conditions, deviations from the optimum cause a reduction of the activity, depending on the degree of the deviation. Moderate deviations produce only small activity decreases which can be tolerated (Figure 1), and so the physiological conditions prevailing in the cell may be taken as standards for at least of the mammalian enzymes. However, assay procedures are usually adapted directly to the features of the individual enzyme and not to obey general standards. Enzymes are sensitive substances present in small amounts and their activity in the cell can often be detected only at their optimum conditions.".

Royal Society of Chemistry - "Enzymes - Function and structure":

"As the temperature rises, reacting molecules have more and more kinetic energy. This increases the chances of a successful collision and so the rate increases. There is a certain temperature at which an enzyme's catalytic activity is at its greatest (see graph). This optimal temperature is usually around human body temperature (37.5 °C) for the enzymes in human cells.
Above this temperature the enzyme structure begins to break down (denature) since at higher temperatures intra- and intermolecular bonds are broken as the enzyme molecules gain even more kinetic energy.".

Note: Wikipedia: "Wilson's temperature syndrome":

"The American Thyroid Association (ATA) describes Wilson's syndrome as at odds with established knowledge of thyroid function. The ATA described the diagnostic criteria for Wilson's syndrome as imprecise and non-specific, and raised concern that the proposed treatments were potentially harmful. Florida State Medical Board members described Wilson's syndrome as a "phony syndrome" and a scam during disciplinary action against Wilson."
...
"The ATA stated in 2005 that a "thorough review of the biomedical literature has found no scientific evidence supporting the existence of 'Wilson's Temperature Syndrome'." The statement added that the mean temperature of normal persons in the AM on waking is 97.5 °F, not 98.5 °F, and that many of the symptoms described by Wilson are nonspecific and typical of depression, anxiety, and psychological and social stress. It also notes that a similar set of symptoms occurs in the alternative diagnoses of neurasthenia, chronic fatigue syndrome, fibromyalgia, multiple chemical sensitivity, chronic Epstein-Barr virus syndrome, and chronic candidiasis. Finally, the Association notes that chronic supplementation with triiodothyronine (T3) is particularly difficult and problematic, since various tissues set their own cellular levels of this hormone by making it individually from thyroxine, and supplementation of T3 may overwhelm this normal regulatory mechanism in some of these tissue.".

Reference: Wilson's Temperature Syndrome

"Metabolism Dependent on Enzymes"
"Enzyme Function Dependent On Temperature":

"... when an enzyme-dependent chemical reaction is monitored for how well it takes place at various temperatures, the lower the temperature, the slower the chemical reaction. As the temperature is increased, the reaction rate will go faster with each increase until it reaches its optimum reaction rate. If the temperature is increased too much, the rate of reaction will diminish due to denaturing or change in shape of the enzyme.".

The treatment suggested by Wilson is what was discredited, the fact that enzyme reactions proceed differently at different temperatures is still supported. Reference to his article was included due to the partial overlap with established knowledge.

I think you are the only one that answered the rather indirect question of why body temperatures are above ambient.

Those are some interesting citations, but I think this answer misses the other advantages of an elevated body temperature.

@BryanKrause I am expanding my answer.

Interesting. I was hypothesizing that perhaps our DNA developed in a warmer environment and we developed adaptations for cooler environments. Is there any possibility of that scenario?

@NonSecwitter I've made another update, I believe it explains that. Poikilotherms adapted to be conservative while homeotherms adapted to high energy activities and maintaining a larger brain. I think your 'DNA question' deserves its own space, but the short answer is that each developed its own taxa in either environment.

First, let's learn about the vocabulary to describe how living beings deal with their internal temperature with this answer. Now that you have read this answer, you understand that humans are homeo-endo-therms.
There are pros and cons of homeothermy. Those pros and cons depend upon the species and esp. upon the type of environment experienced by the organism. Here is one pro and one con. In the specialized literature, you;d find a much more exhaustive list of pros and cons
Pro
The activity of most chemical reactions are affected by temperature. See this post, this post and this post for examples (this post might also be of interest). Enzyme activities are typically highly dependent upon the temperature.
Homeotherms have the advantage that their internal working is not too affected by the outside temperature allowing them to maintain a high metabolism and a high level of activity in a variety of environmental conditions.
Con
Depending upon the environment and the species, it may take a lot of energy (and other ressources) to maintain a constant temperature. For example, in mammals we see behaviours such as shivering, hair positioning (piloerection), vasoconstriction, sweating, change in body posture and other systems such as non-shivering heat production by brown adipose tissues.

Consider if cavemen would be efficient at defending and fighting each other and predators if they took 15 minutes to warm up from a cold nap before they can start to move.
Animals with wider temperature ranges have to maintain many enzyme genes for enzymes that work at different temperatures, and that's inefficient.
If an animal is warm, it processes food and grows a lot faster, so it makes sense for all growing animals to be warm day and night if they can. Older animals can build up fat and reserves and milk and offspring faster if they are resting warmly also. So a female human would benefit from being warm from age 0-37 to breed.
Bears can be dormant at 33'C and alaskan marmots can adjust to 3'C.
Humans that don't hybernate have to be active every day, and have to survive the nights, and grow fast, and build up fat reserves, and keep the immune system enzymes and antibodies at their most performant.

You perhaps need to consider that it's not just humans.  All mammals have body temperatures in a fairly narrow range - 97-103 °F/36-39.5 °C.  Birds likewise have a narrow temperature range, though a bit higher, around 105 °F/40.5 °C.
The advantages seem fairly obvious, at least if you've seen reptiles in cold weather torpor.  As another answer points out, the speed of chemical reactions varies with temperature.  Maintaining a constant temperature allows those reactions (which ultimately determine the speeed of everything the body does) to happen at a constant rate, so animals can be equally active in everything from polar ice to tropical jungle.


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Cerebral activity during exposure to non - visible light
Our eyes only have the ability to sense light within a certain spectrum. My understanding is that particular frequencies energize specific cells in our eyes, each responsible for a different "color". When these cells are energized, they each release an appropriate amount of their chemical transmitter to stimulate additional cells and create the perception of the object from which the photos originate.
At what point does this process not occur for non-visible light?
In other words, do we fail to see non visible light because our eyes lack the receptors for other frequencies, or does our brain receive signals that it just dumps because it has not developed to process the information?
Have there been any experiments done involving a brain scan while exposed to non visible light?

[D]o we fail to see non visible light because our eyes lack the receptors for other frequencies, or does our brain receive signals that it just dumps because it has not developed to process the information?

It is because our eyes lack the receptors for other frequencies.
Humans have 3 'color receptor' called cone cells. We have three types of cone cells, each sensitive to a specific range of wavelengths. Here is a diagram of the sensitivity of each of these three types of cone cells.

As you can see, we do not have receptors for wavelength below 390 nm or above 700 nm which is our visible spectrum.

Awesome, thanks. I guess I was kind of hoping for some hidden brain activity  :-D

Vision is based on a protein interaction with a molecule called retinal from vitamin A.
Wavelengths of light in the visual range cause a photoisomerization of retinal (a cis- to trans- change), which is sensed by the protein that is "holding on" to the retinal.
Wavelengths that do not cause this photoisomerization cannot be sensed by the photoreceptors of the retina, so there isn't any signal produced to transmit to the brain.
However, there is some filtering done by the lens of the eye. Without the lens, humans (and other animals) can see further into the UV range. That UV light is also damaging to the retina, though, so it's best to keep the lens intact.
Note that the image in the answer by @Remi.b is actually from a psychometric experiment, so the lens is intact. The responses there are actually human perceptual sensitivity to light for each cone. The blue curve would go off to the left quite a bit further into the 300nm range if the lens were not present. The research subjects probably prefer the experiment as-is, however.
You wouldn't perceive that UV light much differently than a far violet color, however, because differences between different cones are necessary for color vision, and by that end of the spectrum only the cones responsive to the shortest wavelengths are responsive at all.

Of course, we do detect infrared and ultraviolet light in a sense. We feel infrared (heat) and UV can cause skin issues. You could say that the brain detects this, but you can't make out the form of an emitting source.

@JackR.Woods Those are completely different processes from vision. Chemically, sensing heat and UV are totally different from the processes that occur to detect visible light in the retina.


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Why do plants store energy as carbohydrates and not as fats?
In my introductory biology class, we are learning about biomolecules. The textbook says fats are a more efficient energy store than carbohydrates.
So my question is - why would plants store their energy as carbohydrates and not as fats, if fats are a more efficient energy store?

What research have you done before asking it here?

Asked my professor :P He suggested it might have been because plants don't have an inconsistent source of energy in the same way that plants do, but that didn't make much sense to me.

Not a homework problem! Although I guess there's not much I can do to convince people of that... Just a question I asked in class that my prof. didn't have a satisfying answer for.

I'd imagine since plants are already making carbohydrates and it would waste energy turning sugars into fats, there is just no benefit for them. Keep in mind that for plants and animals the majority of the calories we burn are carbohydrates, but plants will make more everyday while animals have to find it, and thus could go several days without. This is just supposition however.

Note that plants do commonly use fats for storage in at least one context, that of seeds (which humans exploit for edible oils). Seeds need to be compact for dispersal, so the high energy density is an advantage.  The stored fat is used by a small plant (the seedling), so transport issues are less severe than in larger plants.

Great question!  Agree with @John 's ideas.  Also, the main advantage of fat is that it is compact --- it stores more energy per volume than sugar polymers --- and a compact storage form is important to animals which need to move around, but probably not such a big factor for plants.  Just a thought.

Found this page  http://www.techno-preneur.net/technology/tech-trends/agriculture/animals.html  that contains several arguments that make sense to me at least.  It's hardly a textbook, but perhaps gives some ideas.

There are quite some reasons for why plants prefer carbohydrates for energy storage rather than fats. I will reach some of them one at a time.

Fat hates water: By just applying some common sense, one would get to know that fats are hydrophobic, meaning they literally 'hate' water i.e. don't dissolve in water. So, they cannot be transported very easily. On the other hand, most carbohydrates are water-soluble and can be easily transported via phloem fibers. So, plants prefer to use carbohydrate instead of fat. But they can store fat, by converting them into lipoproteins, by binding them with fatty-acid binding protein, by storing them as fatty-acids (i.e. with terminal -COOH which makes them a bit water-soluble) or by storing them in special compartments called elaioplasts. Yet, as one might assume, this would require more energy intake than using carbohydrates, so plants don't prefer this process too much.
source
Plants don't want to store everything: Obviously, plants photosynthesize because they need energy, and because they need energy to survive. So, storing every bit of energy would not be very clever, they need some of it handy. Fats are storehouses of energy i.e. they store energy for extreme conditions, when there is no primary energy source left. Under normal conditions, and at night, carbohydrates are the primary energy source.
Cells don't let them in: Plasma membranes are semipermeable, quite a general fact. So, they do not allow large molecules to enter inside. And fats are one of the largest biomolecules (after, obviously, nucleic acids). So they cannot be transported inside or outside cells. You would say 'but cells are the ones which make fats, so they are already inside!' No, that is why there is phloem, because there are cells which don't synthesize them (say, root cells). On the other hand, carbohydrates, being much smaller, can be transported through small channels or even through simple diffusion through the plasma membrane. Also, as already stated, fats are quite hydrophobic, unlike carbohydrates. So, they are, in a sense, repelled by hydrophilic layer of cell membrane just like water itself hates it. So, they find it even more difficult to cross plasma membranes because of combined effect of size and hydrophobicity.

There can be lots of other reasons which I can't think of right now, but I hope even this much is helpful.

A good effort, but I'm afraid I don't find the arguments very convincing. (1) "Fat hates water" -- but lipoproteins and fatty acid binding proteins solve this problem. (2) "Plants don't want to store" -- possible, but sidesteps rather than answers the question I think, and probably plants do need some energy stores. (3) No, membrane impermeability is due to hydrophobicity, not size; and see nr 1. (4) This is pure speculation, and the description of cardiovascular disease is completely off -- lipoproteins are nanometer scale particles and they do not "get stuck" in blood vessels.

(1) Still, molecular mechanisms have evolved for handling lipid solubility, and plant cells do in fact use these to store fat, see for example http://www.sciencedirect.com/science/article/pii/S0968000498013498. Therefore, solubility is likely not the answer. (3) No, I mean lipids are not that large (triglycierides ~1000Da) and size is not the important factor. (4) I think you have got the wrong impression from that web site. Atherosclerotic plaques result from inflammation, not cholesterol "sticking" to the vessel wall. I suggest you delete/revise this part of your answer.

The reasons stated are equally true for animals (specially first, third and fourth), but animals they do store fats.

My point is not to criticize the poster for accepting your answer — I should have expressed myself better. Clearly he doesn't know the answer to the question, so one cannot expect his judgement to be perfect. However, when an accepted answer is incorrect, as in this case, it is important to comment on the incorrect answer, pointing this out. Otherwise other readers may not realize why it is wrong. No hard feelings. We all have our areas of experties and we all make mistakes. In your place I'd delete your answer,  but that's entirely up to you.

Actually, hydrophobic means "lacking affinity for water", and literally means "fearing water", not hating it, from the Greek phobos meaning "fear"

It doesn't change much about the answer, except you said literally hating water, which is wrong. So at least that part of your answer is incorrect. It was a comment, not a down vote.

No, the problem is not just wording ("sticking", "clogging" or whatever). The idea that triglycerides or even lipoproteins would get stuck in vessels because of their size is simply wrong. Even the thinnest capillaries are several micrometers, and lipoproteins are tens of nanometers. And this does not occur in atherosclerosis --- the lipid buildup occurs inside the vessel wall and is associated with inflammation. (This atherosclerosis stuff is really beside the question here, but the analogy is still misleading.)

@another that's not the point. The point is you said literally, which is incorrect. Hydrophobic does not literally mean "hates water". It literally means "fears water". That is a fact. I'm not saying "hydrophobic" isn't the right word to use, or that "hates water" does not convey an appropriate meaning.  I'm saying that your claim of what it literally means is incorrect. I have now said the same thing half a dozen ways; hopefully you understand. I can't think of way other ways to say it, so let's leave it at that.

@another you still don't understand what I am saying. There isn't a significant difference in meaning, but it's nevertheless incorrect. Let me try this way: Remove the word "literally".

The question was:

Why would plants store their energy as carbohydrates and not as fats, if fats are a more efficient energy store?

But before trying to answer it you have to be quite clear what is meant by efficient. Without qualification this term is meaningless. A little reflection will tell you that whatever positive properties are implied by ‘efficiency’ may have different importance in relation to the very different modes of existence of animals and plants. One will also want to test any explanation on the exceptions — the instances where animals store carbohydrates (generally polysaccharides) and plants store fats. With this in mind I argue as follows:
1. Carbohydrate is the straightforward solution
Plants synthesize glucose from carbon dioxide, animals take in carbohydrates in their diet and break them down to monosaccherides. Hence, storing excess as polysaccheride (glycogen in animals, starch in plants) involves developing and using a relatively simple polymerization/depolymerization system. One would therefore assume it to be the default. The question is then, “in what circumstances is it advantageous to store surplus as fat?”.
2. Fat is a more concentrated energy store, so is used to minimize weight
Dull eh? But that’s the answer. The following extract from Berg et al. explains this clearly (triacylglycerol is the chemical name for triglyceride or fat):

Triacylglycerols are highly concentrated stores of metabolic energy because they are reduced and anhydrous. The yield from the complete oxidation of fatty acids is about 9 kcal g–1 (38 kJ g–1), in contrast with about 4 kcal g–1 (17 kJ g–1) for carbohydrates and proteins. The basis of this large difference in caloric yield is that fatty acids are much more reduced. Furthermore, triacylglycerols are nonpolar, and so they are stored in a nearly anhydrous form, whereas much more polar proteins and carbohydrates are more highly hydrated. In fact, 1 g of dry glycogen binds about 2 g of water. Consequently, a gram of nearly anhydrous fat stores more than six times as much energy as a gram of hydrated glycogen, which is likely the reason that triacylglycerols rather than glycogen were selected in evolution as the major energy reservoir. Consider a typical 70-kg man, who has fuel reserves of 100,000 kcal (420,000 kJ) in triacylglycerols, 25,000 kcal (100,000 kJ) in protein (mostly in muscle), 600 kcal (2500 kJ) in glycogen, and 40 kcal (170 kJ) in glucose. Triacylglycerols constitute about 11 kg of his total body weight. If this amount of energy were stored in glycogen, his total body weight would be 55 kg greater.

The animal exception — glycogen
A limited amount of fuel is stored as glycogen in animals. The increased weight load is offset by the advantage of rapid mobilization and the fact that glucose is obtained (animals cannot convert fatty acids to glucose).
The plant exception — oils in seeds
Plants do not walk around, so weight is not generally a consideration that would induce them to store their reserves as fat. They can develop large tubers under the ground, for example. However there is an advantage to minimizing weight in the energy reserves required for the development of seeds — it allows for easier spreading in the wind or through animal consumption. Thus one can rationalize why the energy reserves in seeds are oils (lower melting point triglycerides on account of their greater unsaturation).

Here is my try.

Why do plants store energy as carbohydrates and not as fats?

Is it because they can't? That isn't the answer as we have corn oil, palm oil, coconut oil, olive oil, sunflower oil etc. So plants can and do store energy as lipids.
Perhaps the question is better rephrased as "Why isn't the main store of energy in plants lipids like mammals."
My guess is because plants do not move as actively as animals. A plant is rooted to a spot by its root system. Hence there isn't an advantage of a storing energy in a high density manner, particularly when lipid synthesis takes more energy compared to sugar synthesis.
So aside for specific examples, there is no advantage to store energy in lipids for a plant. There is no need to pay for a compact source of energy when you will never move as an adult.
As a seed... that may be useful... and this is why all our plant oils comes from seeds of one sort or another.

Quick answer: Animals need mobility while plants favour stability.
Explanation: As you mentioned fat is a more effective storage form of energy. Plants though, reserve energy through starch (carbohydrate) and not through fats as it would be expected. This doesn't mean they don't use fats at all (i.e. oil seeds).
An energy storing molecule must save energy (as the name indicates), but it shouldn't be too heavy and it should be stable enough so that it's functional within the organism. Fat is the most lightweight molecule storing energy. One gram/fat stores more energy than one gram/starch or protein. Thus, the weight of a moving organism would be less if it stored fat instead of starch. But plants don't move around so weight saving is not a real necessity.
So, a heavy starch molecule is more stable than a lighter fat molecule which is comparatively more important for plants in order to provide long-term stability. Another reason why they store mainly starch instead of fats is alternate flowering for example, where the plants save up some starch every year (depending on the plant) and then use all the saved energy at once while blooming. Fats wouldn't have lasted for that long because when fats or oils are exposed to air, they react with the oxygen or water vapor and form short-chain carboxylic acids.


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Why is therapeutic index a ratio instead of an interval?
The therapeutic index of a drug is defined as its toxic dose ($TD_{50}$) divided by its effective dose ($ED_{50}$).  Why is it defined as a ratio rather than the difference $TD_{50} - ED_{50}$?
For example, if drug A has an effective dose of 1 ml and a toxic dose of 2 ml, and drug B has an effective dose of 50 ml and a toxic dose of 100 ml, then they both have the same therapeutic index (2), but intuitively, I would say drug A is much more dangerous, which is reflected if we take the difference instead.

Most drugs are measured by mass - they are then dissolved in some solution or incorporated with fillers into pill form.
If you are worried only about a difference, say from measuring out a volume to be given intravenously, then it would be trivial to solve that issue by dilution: you could take your drug that was dissolved in 1 mL, dilute it so that you are giving 50 mL instead, and make the difference unimportant. The ratio, however, stays the same, regardless of formulation.
A ratio is also much more likely to come up in clinical practice. Take your example, where the toxic dose is only 2X the effective dose. That means that an error where a drug is accidentally given twice could be a serious problem. It doesn't really matter if the volume delivered is small or large, just that someone doesn't realize the drug was already given.


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Where to download gene list of human genome?
I am looking for a place where I can download a full gene list of human genome. Either by HGNC symbol or ensemble ID as long as it is usable on the consensusPathdatabase. Up until this point I have only found fasta files which include a bit too much information and unfortunately not in the format I would like. I am not in the biology field myself so if I am asking for something unreasonable call me out on it!
Reason for this is I am trying to stress test an application that uses the output tabular forms from the gene set analysis tool on consensusPathbase. The stress test on the entire human genome seemed to be the best option as a bigger data set than that will probably not occur.
Thanks in advance

The database you are looking for is ensembl [Yates (2016)].
Go here and chose  Customise your download. There you can select a dataset (e.g. genes and then specify human genes - currently uses build GRCh38; you can also go the same way here to do the same for hg19/GRCh37).
After chosing your dataset, you can click on Attributes to specify what to include in your download (HGNC symbols, IDs, regions, GO terms, and a ton of other stuff), click on Filters to apply filters to your choices (only genes from a chromosome, region, and a ton of other stuff).
Then click Results and download your selection in a format of choice.
(Hint: click Count first and use it as a a sanity check to see if the number of selected genes fits your expectation.)

This is exactly what I was looking for. Thank you very much for the help!


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Chemical methods to detect cell division
So I have been working on a project for a while, and there is one mechanism that I need a little bit of advice about.
The project is chemical-biology based, so don't be deterred :)
Theoretically, by this point in the experiment:
I put cells (let's say lymphatic or endometrial) into stasis, through means of lyopreservation, and now, I have brought them out of stasis, through exposure to a sucrose (trehalose)-based medium.
Now I am attempting to chemically detect mitotic growth within the cells, how can I do this?
This is where the chemistry comes in: My first thought was to use a chromatic indicator that would fluoresce or irradiate in response to mitotic acceleration, but I have not yet found a suitable chemical. In research, I found that a similar experiment had been done in bacteria, and the chemical dimyristoylphosphatidylcholine (1,2-Dimyristoyl-sn-glycero-3-phosphocholine) had been used. Would this work in mammalian cells? Another idea was to use a chemical that detects the unnatural growth from the spindle fiber and centriole point of view, reacting when the centrioles entered the phase to replicate. I have been unable to find any chemicals that make use of the replication of centrioles, or the spindle fibers, so I need ideas.
To summarize: Does anybody know of any biochromatic indicators that react through detection of rapid, mammalian, mitotic growth? Not necessarily cancerous and uninhibited, but rapid meaning 'a speed of mitosis that is faster than the norm.' Preferrably, the indicator would be able to stay in stasis for extended periods of time.
If such an indicator is not available (or you do not believe so) then does there exist a biochromatic indicator that reacts in the presence of any sort of cell division?
Is there a way to chemically detect cell division?
I am welcome to all ideas.

There is one important experimental detail missing: do you want to 'keep' the cells you measure growth in, or can they die as a result of the measurement?

They can die, but only after it has been determined whether or not they were growing.

There are many methods to study the cell cycle, and it's not clear to me exactly what you want to measure. What do you mean by "mitotic growth"? Mitosis is a specific event in the cell cycle (separation of chromosomes), are you attempting to detect mitosis events specifically? This is distinct from measuring DNA synthesis, or merely the DNA profile as @Nicolai suggests, which would rather indicate proportions of the cells in the difference cell cycle phases. Cell growth is also different from proliferation. Please clarify.

I desire a chemical which would change color in the presence of cell division, at the bare minimum. Specifically, it would be nice to detect if cell division was faster than normal. Whether this is done through DNA or telomeres, I have no preference.

The most common indicator for the growth of any kind of cell (population) I know of is the amount of DNA in that cell. There are a number of (fluorescent) dyes that bind to DNA in a stoichiometric fashion and can therefore be used to determine the (relative) amount of DNA inside a cell (is hope that's what you mean with 'biochromatic indicator'). The most common dye used in this way is probably DAPI.
In order to determine which cells are dividing, you'll obviously need a device that can measure the fluorescence of each cell individually- so either a microscope or a flow cytometer. Because growing mammalian cells (it seems to me that's what you want to look at) multiply their full set of diploid chromosomes in the S-phase of the cell cycle, you can discriminate growing cells from others by their relative DNA amounts:

A non-growing cell has only the diploid chromosomes (1x relative DNA)
A growing cell will have either the doubled set of chromosomes (2x relative DNA) if it sompleteded S-phase or an intermediate amount (1-2x relative DNA) if it's currently in S-phase

Figure 1 of this (really old) paper also shows, how DNA amounts can indicate at which point of the cell cycle a cell is (which tells you if its growing) works.
A note on cell viability:
Staining any kind of cell with DAPI (or most other dyes that bind to DNA) will most likely kill it or at least act as a very strong mutagen. Based on your answer to my comment this should not be a problem.
While not really part of your question, you mentioned that you want to preserve cells using lyopreservation, which basically means drying them. You should consider, that mammalian cells will most likely not to survive this process (unlike plants and some invertebrates there are no mechanisms in mammalian cells to protect them against the water loss). Without sorting the live cells from the dead ones first, your measurements may detect cells that were dividing prior to the preservation.


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Organism and plants reduce radioactivity?
I would like to ask if there are organisms or plants that could help in reducing any one of types radioactive contamination?

What do you mean by "reducing"?

Your magic search word is 'phyto-remediation'
There a bunch of plants used for this.
None of them remove radioactive material as such.  With the possible exception of deuterium, the chemistry of isotopes aren't distinguishable by biological organisms.
So to remove strontium 90, you need something that picks up strontium.  It will pick up both the radioactive and non-radioactive forms.
In some cases the metal will combine forming compounds.  This may make the radio-isotope inaccessible to a given plant.  If, for example, strontium was in the form of SrO and SrSO4 you might need two different plants, or add a reagent to the soil to convert it to an accessible form.
Once the plant tissue has picked up the radio isotope, the usual process is to drive off the plant tissue by burning or destructive distillation, then processing the material to either make it insoluble for disposal, or convert it for use.  For material with a fairly short half life and low solubility, it may be sufficient just to bury it.

I recall reading that sunflowers were planted after the Chernobyl nuclear disaster, and I just now read that fields of sunflowers were also used in and around Fukushima.
Apparently sunflowers have an affinity to absorbing toxic heavy metals from the soil.  The radioactive isotopes are stored in their stems and leaves. The plants have to be cut down and disposed of as radioactive waste.  However, that cost is considerably less than digging up and disposal of topsoil.
Doing a brief google search, I learned other plants such as certain mustard plant species and other herbs can be used for lead and mercury environmental damage.  To learn more, I encourage you to spend a little time using your favorite search engine.  Undoubtedly you'll learn more than what little I have shared now.


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Intersex Genetalia
Hypothetically if someone who is born intersex has both sets of fully functioning genitalia (one male one female) could they potentially self fertilize? And if so would it be possible for any genetic variation to take place?

Coincidentally, I was just reading about this today on Wikipedia.

Someone born intersex does NOT have "both sets of functioning genitalia". It simply does not happen. That is a common misconception. Nearly every male organ has a female equivalent. The same embryonic tissue for each organ develops as male, female or gets stuck in between. Which parts do what depends on the specific condition. One cannot have a clitoris AND a penis for example because both  come from the same original structure. The only exception are the organs originating from the Mullerian Ducts (female) and Wolffian Ducts (male) but again it is nearly impossible for both of those to develop as fully functional in the same person.
Also, when both an ovary and a testicle develop it is because two embryos joined together forming a composite human with two different sets of DNA, one forming an ovary and the other a testicle. The genitalia would be rather jumbled making fertility as one sex difficult and as both sexes pretty much impossible.


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Help in identifying crusty formation on Eucalyptus leaves
I am working with the plant species Eucalyptus perriniana (spinning gum) for one of my research projects. A few days into the experiment, I noticed some crusty deposits forming on several leaves (as shown in the attached photographs). I was wondering if anyone here might be able to identify it. I am not sure if the deposits are biological in nature, or if they are some kind of chemical precipitate.


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How did mosquitoes expand their habitations to a place they never lived before?
So, in the region I live, we have some sort of like a "mosquito zone", spanning for thousands of Kilometres, this is the place where you will normally find lots of mosquitoes, and this has been so for years and years. But last year, we were surprised to see that the mosquitoes have "invaded"a village which has never experienced them even once. The village though, is at the border with what I call "mosquito zone" but never has these insects "visited" this village. So I became curious to know, what has happened so that the mosquitoes said "now let's invade this village and live there"? I can't see anything suspicious that has changed. Do we have any explanations?

It could be a number of things. Mosquitos need standing water. Look for that. Any changes? Was last year particularly rainy?  One group of mosquitos lays its eggs at the waters edge. They lie dormant until the water reaches them again. If the water was high when the eggs were laid, then recedes, it may be years before the water reaches them again and the eggs hatch, resulting in a bloom of high numbers. Also, other mosquitos breed in containers. Things like tires, or coffee cans, or flower pots in cemeteries. Even a small amount of stagnant water in a container can result in mosquitos. Any changes there? The obvious change is the warming climate, but I would look first to changes in the water.


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Did early 20th century researchers state why they used E. coli as a model organism?
I am investigating the early uses of E. coli as a model organism. Sadly, many early 20th century papers are not in English. In those that are, I have been unable to find explicit statements as to why a researcher chose to use E. coli as a model organism.
Does anyone know of early literature in which this reasoning is stated? I imagine that prior to the widespread use of E. coli, scientists would have had to argue why they chose to use it to investigate biological phenomena not limited to this bacterium alone.

Nobody justified the organism then, nor did they need to. If they had discovered something that was new then it was publishable. This "model organism" thing is a recent phenomenon driven by medical research funding and political pressure. What is valid in relation to your question is when E. coli started to be used and why. If you can cite any papers you have found do so, irrespective of language. It's only sad for you. Many of us here in Europe speak or read German and French (the most likely languages in this respect) and other European languages.

@user297623, while my answer is given below, I'd be curious to read some of the early 20th century French articles - to which you likely refer, but couldn't get a copy of their text, or find an online copy. If there were online copies: could you add a link?

Historical Fallacies implicit in the Question

“…why a researcher chose to use E. coli as a model organism.”

Researchers did not work with E. coli because they regarded it as a “model organism”. They worked with it because they were bacteriologists and it was a convenient bacterium to use. As Joshua Lederberg wrote in Microbiology Today (2004):

From the beginning, although pathogenic strains were also found, E. coli was used as a representative, harmless bacterium that could be safely and easily cultivated even on synthetic media. On rich media, it will grow with a
  doubling time of 20 minutes; hence readily visible colonies can be seen overnight when it is plated on agar. Specialized media, like MacConkey’s agar,were developed for the selective isolation and identification of E. coli, as this was used as a global indicator for the pollution of water supplies. Hence, during the first half of the twentieth century E. coli was well known to bacteriologists. However, it was rarely, if ever, mentioned in general biology texts, as bacteria were generally regarded as pre-cellular in complexity and devoid of the nuclei and other genetic apparatus of ‘real’ organisms.

Indeed the term ‘model organism’ was not used in this sense until about 1970, as this Google ngram shows.

“I imagine that prior to the widespread use of E. coli, scientists would have had to argue why they chose to use it to investigate biological phenomena not limited to this bacterium alone.”

You imagine wrongly. They were not sitting down and saying “we want to study this biological phenomenon, what bacteria shall we choose?” and certainly not having to justify themselves on publication. In general they published in specialized bacteriological journals where audience and referees would know why they were using E. coli or whatever. Even when Tatum and Lederberg (see below) published a letter on bacterial recombination in the general science journal, Nature, in 1946 they did not waste space on species justification:

No. You are imposing modern attitudes — governed by the contemporary state of science and its funding — upon the science of a completely different era. That is not the way to approach history.
Why did E. coli become the most studied bacterium?
It would seem that the discovery of bacterial recombination in E. coli by Lederberg and Tatum (for which they shared the 1958 Nobel Prize for Physiology or Medicine with George Beadle) was one of the key factors leading to the expansion in the use of E. coli (see Microbiology Today article previously cited). This phenomenon was originally suggested by studies on the transformation pneumococcal bacteria, but its demonstration in the bacterial workhorse, E. coli, opened the doors to the use of a wide range of genetic techniques that could be used for biochemical, as well as molecular biological, studies.

Very interesting question.

Did early 20th century researchers state why they used E. coli as a model organism?

In short: No (at least in the 1920ies). For instance: Werkman 1927: Vitamin Effects in the physiology of microorganisms does not provide any justification.
Similarly, a recent review by Blount, 2015, eLife: The unexhausted potential of E. coli states:

E. coli's meteoric rise and exalted status in biology stem from how
  easy it is to find and work with. Hardy, non-pathogenic, and versatile
  strains that grow quickly on many different nutrients can be isolated
  from virtually any human. These traits made E. coli a mainstay in
  microbiology teaching lab collections. Consequently, when early 20th
  century microbiologists cast about for a model organism, E. coli was
  one of the most widely available choices.

However, when E. coli entered research in the 19th century, and thus a few decades earlier, it wasn't introduced as a tool or model or teaching material. When it entered science it immediately did so as part of one very profound and important discovery about human digestion, as reviewed by Shulman et al., 2007, Clinical Infectious Diseases

Escherich described in detail Bacterium coli commune (the common colon
  bacillus now known as Escherichia coli) and Bacterium lactis aërogenes
  (now known as Klebsiella pneumoniae). He demonstrated their
  fermentation characteristics and the nature of the gas produced during
  fermentation, and he showed that, under anaerobic conditions, growth
  was totally dependent on carbohydrate fermentation. Breaking with
  dogma, Escherich concluded that any role of the intestinal flora in
  nutrition was minor at best.

While only peripheral to your main question: E. coli's second boom during the mid of the 20th century, where it entered the field of genetics (that has been occupied by other organisms before) occurred because of discovery of the ability to exchange DNA between individuals - as reviewed by Telis et al. 2014: A Bibliometrics History of the Journal GENETICS (... which would then promote further discoveries relating to the handling and manipulation of DNA...).


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Are all enzymes proteins?
So throughout my education and research career I have been taught that all enzymes are proteins. This makes sense when you consider enzyme denaturing and folding/shape etc. However, I was recently told by a biology professor that in fact, not all enzymes are proteins -- and he alluded to the RNA world hypothesis and rRNA's.
Could someone explain further how exactly an rRNA (or similar) could be (or not be) considered an enzyme, and whether or not all enzymes are proteins etc?
Thank you!

You need to read about ribozymes, and a lot of people were surprised in 1982 when they were discovered. You can find ample information on this wide topic on the web, which is why I am voting to close.

Disclaimer
I voted to close this question as it struck me that the by giving the poster the magic word ‘ribozyme’ he could easily verify for himself that the answer to the question in his title was “No”. However, as this question received answers that I find incorrect or misleading, I provide my own answer to put the record straight.
History and Terminology
Although I would not necessarily regard entries in Wikipedia as authoritative, scientific dates are not particularly contentious, so I refer the reader to the entries on Enzyme and Protein for the following:

The first enzyme to be discovered is said to have been diastase, in 1833, although the opposition of Pasteur to the idea of metabolic activity outside of living things delayed the acknowledgement of this. The word enzyme was coined in 1877 from the Greek, meaning “in yeast”. The catalytic activity of the enzymes of fermentation was studied intensively in the late 19th and early 20th century, culminating in Buchner’s Nobel Prize in Chemistry in 1907.
Although proteins had been recognized in the 18th century, and named by Berzelius in 1838, their chemistry as polypeptides was not established until 1902, and it was not until 1926 that Sumner established that urease was a protein.

Hence, the word enzyme and the concept of its activity was introduced long before the chemical nature of most enzymes as proteins was established, and therefore the poster is correct in not including protein in the definition of enzyme. It is also correct to talk about the later discovery of enzymes that are RNA rather than protein, despite the fact that the latter confounded a general belief that had held for over a half century. Indeed, RNA enzymes are referred to by a special designation — ribozymes — just as most members of genus Cygnus are referred to as swans, but Cygnus atratus is usually referred to as black swans.
RNA enzymes (ribozymes)
A perfect example of an RNA enzyme would be one that was naturally active in the absence of protein and showed catalytic activity against a distinct substrate. As of 2002, when the topic was reviewed by Thomas Cech — who, together with Sidney Altman, received the Nobel Prize in Chemistry for the discovery of the first ribozyme in 1962 — there were no such natural examples.

The type of catalytic RNA discovered by Cech — the self-splicing introns of Tetrahymena are completely free of protein, but act on the pre-mRNA that contains them.
Another type of catalytic RNA, exemplified by the ribonuclease-P discovered by Altman, is active against a substrate distinct from itself — a precursor tRNA — contains protein as well as RNA. However if the protein is removed from RNase-P under appropriate conditions the RNA component retains catalytic activity.

Despite these limitations — and the fact that the only reactions catalysed are cleavage and ligation of RNA — I would have cited these as clear examples of RNA enzymes if I had been the professor to whom the poster addressed his question. Ribosomal RNA probably has catalytic activity, but is less clear-cut, as I explain below.
The ‘RNA World’ and RNA catalysis of other types of reaction
One of the results of the discovery was catalytic RNA in the early 60s was that it gave flesh to an idea that resolved some of the problems of the early evolution of biochemical processes — especially the interdependence of protein and nucleic acid. This was an ‘RNA World’ in which RNA served both as genetic material (before DNA evolved) and the enzymes for performing biochemical reactions, including that of protein synthesis. However the only reactions catalysed by the contemporary RNA enzymes that had been characterized were the cleavage or ligation of RNA itself.
One could argue that other catalytic reactions were taken over by proteins when they emerged, as they were more efficient etc., however the question remained as to whether RNA had the potential to catalyse such reactions. One step in that direction was to artificially select oligoribonucleotides (aptamers) on the basis of their ability to bind particular small molecules. There have also been reports that a small synthetic RNA can catalyse the amino acylation of AMP-activated tRNA for phe.
The peptidyl transferase activity of rRNA
It is in the context of what I have written above that the possible catalytic activity of rRNA should be viewed.

The reaction involved is that of the peptidyl transferase (below). There are no other examples of RNA catalysing reactions other than RNA hydrolysis and ligation
The implications for the ‘RNA World’ hypothesis (which is not universally accepted) are such that — although I personally favour it (and have lectured to students on it in relation to ribosomes) — one must be very careful not to allow this to cloud one’s scientific judgement.

The evidence for the peptidyl transferase (PT) activity of the large ribosomal RNA (23S rRNA in E.coli, 28S rRNA in H.sapiens) is as follows:

Repeated attempts to associate particular ribosomal proteins with PT activity failed and many individual ribosomal proteins could be deleted from E.coli ribosomes without abolishing the PT activity
Affinity labels of substrates of the PT reaction tended to label RNA rather than protein.
The PT centre has been located in the three-dimensional structure of 23S rRNA by crystalization with analogue of the reaction intermediate. No proteins are in the vicinity of this.

This argues strongly that the PT activity of the ribosome lies in the 23S rRNA — but cannot be regarded as a rigorous proof. Not surprisingly, no protein-free RNA or fragment thereof has been shown to be able to catalyse the PT-reaction between the small substrate analogues that can be used for this.
I happen, myself, to believe that the ribosome is a ribozyme — for the little that it is worth — but I would never put forward the ribosome as an example of a ribozyme, when so much better ones exist.

Until the late 1980's all enzymes* were believed to be proteins, and were often defined as protein catalysts, often in textbooks which are often not perfect representations of science. At that point every macromolecular biological catalyst known was a protein so they thought all macromolecular catalysts were proteins. But the discovery of ribozymes (RNA strands that act as catalysts) changed that. The discovery that one of the most well known enzymes ribosomes had their functional components made of RNA and not protein also played a factor.
NOW enzymes are generally defined as macromolecular biological catalysts and include ribozymes. But older works or outdated textbooks will still refer to enzymes as only proteins but newer works will not. Don't feel despondent I was taught the same thing initially, and it persisted for a several years in college. Part of this is each successive step in education tends to lag behind and/or get over simplified in scientific knowledge. Textbook manufacturers are not overly concerned with poor phrasing or outdated definitions and are rarely writtten by scientists.
*in its object form, originally and for quite a long time enzyme referred to the process not the agent responsible becasue the agent was unknown.

By Definition? What definition? It was almost 50 years after the name enzyme (in yeast) was coined that Sumner (1926) demonstrated that urease was a protein. (as every schoolboy knows). And this answer ignores the way the question was phrased, which implies the poster is talking about a word he regards (quite correctly) as meaning a biological catalyst.

Thanks for reminding me to include the origin of the word. if you believe the OP is making a hidden assumption I did not address, feel free to ask them in comments or post your own answer.

"I have been taught that all enzymes are proteins" This only makes sense in English if one assumes the definition of enzyme does not include its chemical composition.

Actually it works either way, it can mean the definition does not include the chemical composition or that it does included it but it is not "is a protein"

As with @mgkrebbs answer, it would be nice to mention the name of the person who discovered ribozymes: Tom Cech.

Oh, looking for the link, I realized I forgot he shared the prize with Sidney Altman

@DeNovo — Better than mentioning names would be to describe the reactions catalysed by the first ribozymes to be discovered and their total independence on proteins. The case of the peptidyl transferase activity of rRNA is much more complex and even contentious, and needs describing, rather than just asserting. I voted to close this question, but I find the answers unsatisfactory enough that I may have to answer myself. (Sharpen your knives.)

I have been accused of including too much auxiliary information in answers, so  am trying to stick to what is specifically needed to answer and understand the answer to the question.

@David true (better to describe the actual discovery), and also when a question is answered by a nobel prize discovery, I do like to see some mention of the person/history. Especially when it's someone like Cech.

It depends on how you define "enzyme".  Wiktionary says an enzyme is:

A globular protein that catalyses a biological chemical reaction.

Wikipedia says:

Enzymes are macromolecular biological catalysts.

So the first definition excludes anything but proteins and the second also allows other large biological molecules which catalyze reactions.
The important core meaning is that of a biomolecule which catalyzes a reaction, and the restriction to only proteins is somewhat arbitrary.  The expectation for decades was that enzymes (bio-catalysts) were proteins because all the ones that had been discovered were in fact proteins.  Hence the older definition included "protein" as part of the definition.
Once it was discovered that some RNA molecules also have enzymatic action (a discovery awarded a Nobel prize in 1989), many have used the enlarged definition for "enzyme" since the enzymatic action of RNA is important.  When RNA catalysts specifically are referenced, the term "ribozyme" is typically used.
Quite a few ribozymes have now been discovered.  An important and well-known one is rRNA, which forms the core of the ribosome and provides the catalytic sites necessary for translation of mRNA into protein.  Another ribozyme is Ribonuclease P. Group I catalytic introns are a kind of intron which act as a ribozyme whose action is to splice itself out of the RNA transcript of a gene so that a mature mRNA can be formed.

The question was phrased in a way which implies the poster is talking about a word, enzyme, he regards (quite correctly) as meaning a biological catalyst. So if you thought his wording ambiguous, you could have edited it. However the answer does not depend on how "you" or "Wikipedia" define enzyme, it depends on the history of the word and of the science. It was almost 50 years after the name enzyme (in yeast) was coined that Sumner (1926) demonstrated that urease was a protein. (as can be found in sources other than Wikipedia). Black swans anyone?

I do love questions that are answered with a nobel prize. It would be nice to actually mention Tom Cech's name here.


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Is agriculture really a net contributor of greenhouse gases?
A lot of scientific studies and credible sources indicate that agriculture is one of the major contributors of greenhouse gases. The exact numbers seem to vary a lot, I've seen everything from 8% to 45% of global greenhouse gas emissions.
What makes me unsure how to really interpret these numbers is the fact that the process of growing feed to feed livestock, raising livestock, and then eating that livestock, is a cycle. The very same plants that the livestock is eating has during the course of its growth acted as a sink, i.e. absorbing carbon dioxide from the air. This is totally different from pumping oil out of the ground and burning it, which is (in the relevant short term) only production of greenhouse gases, without the sink.
I would assume that any serious study on greenhouse gases would factor in the entire cycle of absorption through animal feed and release back into the atmosphere, yet none of the studies I have seen say exactly how they arrived at the emissions.
Aside from the fact that oil is used in agriculture, when only considering the actual gases released from animal farming vs plant farming, it doesn't really make basic sense to me that there could be a net production of greenhouse gases - where did the surplus come from?

The issue is that it is not always a cycle, when you drain wetlands or burn forests to make more farmland that's not a cycle that is permanent change. A change that can continue having effects for centuries. Then of course you have petroleum fuel used to run tractors and the production of fertilizer which are often not cycles either but pure extraction.
One of the reason the number varies so much is because of disagreements about what falls under agriculture, does the fuel used to run a cargo ship moving bananas count? How about mining equipment used to extract minerals used to make fertilizer? Many simply forget to include things like peat bogs or changes in soil bacteria.
For instance draining a peat bog releases tremendous amounts of carbon, as a functioning net carbon sink is changed into a carbon producer. Sometimes this happens as water is diverted to farmland but often it is done just on purpose to get more farmable land. Exact impacts vary from place to place leading to wide ranges of estimations further complicating it.

Wow, changes in soil bacteria was something I didn't see before... just got even more complex! Maybe I should have been more specific about what I'm really interested in is the claim by some that meat, dairy and eggs are a major (or even THE major) contributor to global warming... but then you need to know how the emissions would change - and a banana cargo ship clearly is still a banana cargo ship even in a 100% vegan world. If we replace meat calories with vegetable calories, wouldn't we sort of replace the farm animals emissions by our own instead (more fuel for harvesting plants, etc)?

Should I perhaps create a new question more along the lines of "How big is the difference in greenhouse gas emissions between today's diet and a 100% vegan diet?"? Not sure if the Biology StackExchange is even the correct place for such a question - it almost seems to be a mix of chemistry, physics and biology?

I reckon this is worth a new question, but off the top of my head, I think there's a figure that it takes 4kg of grain to produce 1kg of meat, or equivalent calorie content. Then methane is a major greenhouse gas and apparently cows are gassy animals, so still very complicated...

@OliverHouston Methane is a major greenhouse gas, but isn't stable in an oxidative atmosphere. We can't ignore it, but it doesn't accumulate. Water vapour (produced when methane breaks) is similar - it's by far the biggest contributor to Earth's greenhouse effect, but the atmosphere cannot really hold more of it - it spontaneously condenses out of the atmosphere.

@BadCash The whole thing is absurdly complex; it can't really be covered in a couple of SE questions. Consider that as carbon dioxide content increases, plants grow faster (lack of carbon is limiting the growth of most plants, not lack of energy; higher temperatures also promote growth, though only up to a point); this may very well cause agriculture to be more efficient (more food per square meter, which means less work for the same amount of food) or less efficient (more weed growth, disease...). Is transportation of meat cheaper or more expensive than fruits, vegetables, grains?

Thanks @Luaan, hadn't heard that methane oxidised in the atmosphere. I think some of the specifics e.g. does meat/crops produce more CO2. But I agree, it is hugely complex when you take into account shipping/growing methods, i.e. is it better to get local veg grown in a heated greenhouse, or naturally grown veg shipped from warmer climes?

@OliverHouston Transportation is ridiculously cheap, especially for non-perishable goods - I don't remember the exact numbers (and can't find the reference), but I recall that the break-even point is somewhere in thousands of kilometers over land (ships are pretty much unlimited). There is always something that can be produced and distributed locally cheaper than imports, but that's rarely a consideration - the main decision is political (self-sufficiency, nationalism, ...). But do consider that we mostly feed the animals with crops, so those can't be more efficient than crops, at least.

@BadCash the type of farming is often more important that what is being farmed, for instance small scale pig farms can often be closed cycle while it is nearly impossible to do with large ones, organic farms can pollute more than industrial due to yield, Many farms are horribly wasteful just becasue of where they are, a farm in kansas can be way more efficient than one in california. Even something as simple as what feed is used matter, in the US we favor corn as feed but not everyone does this, many countries favor barley which is more environmentally friendly

@OliverHouston - how much food per 1kg of meat depends on animal: short living, fast-growing chicken requires like 2 kg of cheap food (insects and leftovers), pig requires more, cow requires 10 kg of grains (suitable also as food for humans) and grass.