Yeast counts in Neubauer improved or Thoma counting chambers
Introduction to counting chambers
Experiments or studies that work with cells require the cells in known and suitable
quantities. There are different methods used to count the cells in a cell suspension.
Despite great advances in science, even today one of the most widely used methods,
due to its simplicity and low cost, is the direct microscopic observation and counting
of cells in cell counting chambers or haemocytometers.
There are many different counting chambers, but their basic usage is common to all of
them. The counting chamber is a special slide with a frame of known surface marked on it,
wherein a fixed volume of the cell suspension under study is placed. By counting the cells
in that particular volume under the microscope, the concentration of cells in the sample
can be estimated. Although these frames can vary a lot (they can be subdivided in different
ways), they usually delimit a square surface of 1 mm/side (1 mm2), which is then subdivided
into smaller squares. When the sample is placed in the chamber and the cover glass is
in the proper position, the sample reaches in most chamber models a height of 0.1 mm.
Thus, by counting cells located in the counting area the number of cells in 0.1 microliters
are accounted (1 mm2 x 0.1 mm = 0.1 µl = 10-4 ml).
If instead of counting all the cells in all squares in the 1 mm2 area, cells are counted
in fewer squares (for example, when the number of cells in each of the squares is very high),
contiguous squares should not be counted. In this case, the medium squares in the corners
and the one in the center are usually counted, and the data will be extrapolated
to estimate the number of cells in the total 1 mm2 area .
Specific information on Neubauer improved counting chamber
Specific information on Thoma counting chamber
Note to Teachers
If you want to use this service for educational propose the following procedure is suggested:
- Provide students with the URL of this page.
- Tell the student to count the yeasts in one of the counting chambers and to solve the problems.
In case the teacher wants to control the activity, it is suggested that students generate
aspecific 8-digit number to receive a corresponding problem, then solve the exercise and
deliver it for correction. The teacher can access the solved problems here.
Exercise number: 96877331 Show a different problem
Please read the entire page before proceeding to solve the problem.
From a yeast suspension two decimal dilutions were obtained up to 10-2 dilution.
Ten microliters of the dilution were transferred to an improved Neubauer counting chamber and
another ten to a Thoma counting chamber.
Count the cells in the counting chamber and calculate the concentration of yeasts in
the initial suspension. Then, find out how to obtain the following suspensions of
- A suspension of 2 ml with a concentration of 5 x 106 yeast/ml.
- A suspension of 3 ml with a concentration of 5 x 108 yeast/ml.
To count cells click on the counting chamber (Neubauer or Thoma) you want to use.
A new window will be opened with a representation of the selected counting chamber.
The resulting image is substantially larger than the screen.
It is likely that the browser will fit the image to the browser's window, so that the
resolution of the image will be very poor. In this case, click on the image to view
the full size image. The user will need to use the scroll bars to locate the counting
area of the counting chamber in order to count the yeasts. This process resembles the
microscopic observation of the counting chamber with a 40X objective, and it is intended
to be used for familiarization with the counting chamber that later could be used in
To solve the exercise, all yeasts in the central big square of the counting chamber
must be counted (25 medium squares in the improved Neubauer chamber or 16 medium
squares in the Thoma chamber). Both counting chambers will lead
to the same result if the center of the counting chamber is counted.
Them, the concentration of the undiluted yeast suspension
must be calculated and the necessary calculations to solve the proposed questions
must be computed.
Counting Chamber: Neubauer improved
Counting Chamber: Thoma
Kwa mfano, katika uchunguzi wa Neubauer na Thoma, chembe za kuhesabu zilikuwa na idadi kubwa ya chembe za kuhesabu. Kuna mbinu tofauti zinazotumiwa kuhesabu chembe katika kusimamishwa kwa chembe. Licha ya maendeleo makubwa ya kisayansi, hata leo moja ya mbinu zinazotumiwa sana, kwa sababu ya unyenyekevu wake na gharama ya chini, ni uchunguzi wa moja kwa moja wa microscopic na kuhesabu seli katika vyumba vya kuhesabu seli au hemocytometers. Kuna vyumba vingi tofauti vya kuhesabu, lakini matumizi yao ya msingi ni ya kawaida kwa vyote. Chumba cha kuhesabu ni slide maalum na sura ya uso unaojulikana iliyochorwa juu yake, ambapo kiasi cha kudumu cha kusimamishwa kwa seli chini ya utafiti huwekwa. Kwa kuhesabu chembe zilizo katika kiasi hicho hususa chini ya darubini, kiasi cha chembe zilizo katika sampuli hiyo chaweza kukadiriwa. Ingawa mifumo hii inaweza kutofautiana sana (inaweza kugawanywa kwa njia tofauti), kwa kawaida huamua uso wa mraba wa 1 mm (1 mm2) upande, ambao kisha umegawanywa katika mraba mdogo. Wakati sampuli imewekwa katika chumba na kioo cha kifuniko kiko katika nafasi sahihi, sampuli hufikia urefu wa 0.1 mm katika mifano mingi ya chumba. Kwa hivyo, kwa kuhesabu seli zilizopo katika eneo la kuhesabu, idadi ya seli katika microliters 0.1 (mm2 x mm1) = 0.1 ml = 10 ml) huhesabiwa. Ikiwa badala ya kuhesabu seli zote katika mraba wote katika eneo la 1 mm2, seli zinahesabiwa katika mraba wachache (kwa mfano, wakati idadi ya seli katika kila moja ya mraba ni kubwa sana), mraba unaohusiana haupaswi kuhesabiwa. Katika kesi hii, mraba wa kati katika pembe na moja katikati ni kawaida kuhesabiwa, na data itakuwa extrapolated kukadiria idadi ya seli katika jumla ya 1 mm2 eneo. "Kama unajua, ""Neubauer Improved Counting Chamber"" ni moja ya huduma za msingi za elimu, na kwa hivyo, ikiwa unataka kutumia huduma hii kwa ajili ya elimu, tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali tafadhali." - Mwambie mwanafunzi kuhesabu chachu katika moja ya vyumba vya kuhesabu na kutatua matatizo. Kwa mfano, kama mwalimu anataka kudhibiti shughuli, ni kupendekezwa kwamba wanafunzi kuzalisha aspecific namba ya tarakimu nane kupokea tatizo husika, kisha kutatua zoezi na kutoa kwa ajili ya marekebisho. Mwalimu anaweza kupata matatizo kutatuliwa hapa. "Kama ilivyoelezwa katika ukurasa wa 96733, ""Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti wa Utafiti.""" Kutoka kwa suspension ya chachu, dilutions mbili za decimal zilipatikana hadi dilutions ya 10-2 Mikrolita kumi za umajimaji zilipelekwa kwenye chumba cha kuhesabu cha Neubauer kilichoboreshwa na kumi nyingine kwenye chumba cha kuhesabu cha Thoma. Hesabu chembe katika chumba cha kuhesabu na kuhesabu mkusanyiko wa chachu katika suspension ya awali. Kwa mfano, unaweza kupata suspension ya 2 ml ya 5 x 106 yeast. Suspension ya 3 ml yenye mkusanyiko wa 5 x 108 yai kwa ml. Ili kuhesabu seli bonyeza juu ya chumba kuhesabu (Neubauer au Thoma) unataka kutumia. dirisha jipya itafunguliwa na uwakilishi wa chumba kuchunguza kuchaguliwa. Picha inayotokezwa ni kubwa sana kuliko skrini. Ni uwezekano kwamba kivinjari itafaa picha kwa dirisha la kivinjari, hivyo kwamba azimio la picha itakuwa duni sana. Katika kesi hii, bonyeza picha ili kuona picha ya ukubwa kamili. Mtumiaji atahitaji kutumia scroll bars kupata eneo la kuhesabu la chumba cha kuhesabu ili kuhesabu chachu. Mchakato huu unafanana na uchunguzi wa microscopic wa chumba cha kuhesabu na lengo la 40x, na ni lengo la kutumiwa kwa ajili ya kufahamiana na chumba cha kuhesabu ambayo baadaye inaweza kutumika katika kutatua zoezi, mayai yote katika mraba mkubwa wa kati wa chumba cha kuhesabu lazima kuhesabiwa (square 25 kati katika chumba cha Neubauer kilichoboreshwa au mraba 16 kati katika chumba cha Thoma). Vyumba vyote viwili vya kuhesabu vitaongoza kwenye matokeo sawa ikiwa kituo cha chumba cha kuhesabu kitatahesabiwa. Katika kesi hii, ni muhimu kuamua kiwango cha uncertainty ya mchuzi wa mchuzi na kuamua jinsi ya kuamua kiwango cha uncertainty. Chumba cha kujitegemea: Neubauer kuboreshwa Chumba cha kujitegemea: Thoma