Growth and Ageing -2 major processes that occur during growth
Table of Contents
Growth occurs as a result of changes that happen in the body. From the zygote to the fetus, to a baby, a toddler, a child, an adolescent, and to an adult, growth occurs consistently.
Merriam Webster dictionary defines growth as the natural increase in size. Growth in humans become visible as height and weight increases, and as they start gaining the ability to perform various activities over time.
When growth fails to happen normally and at the right time, it becomes a call for concern and worry.
Growth is triggered by changes in the requirements of various parts of the body.
For instance, in the third week of fetal life, the cardiovascular system begins to grow and develop because the embryo can no longer meet its oxygen and nutritional needs by only diffusion. This is the signal that triggers growth and development of the heart and its components.
As time goes on, the requirements of the body continue to change requiring the occurrence of growth and maturation.
When a child is born newly, the child is dependent on breast milk for the first six months of life outside the womb. Within this period, breast milk is able to provide sufficient nutrient.
After six months, however, supplementary foods become necessary and the body adapts to this by making the digestive system fit enough to break down foods.
Before the end of six months, any attempt to give other foods will lead to digestive issues.
The major processes that occur during growth are:
The cell is the smallest unit of the body. When cells divide, it leads to an increase in the number of cells. This increase causes parts of the body to mature gradually.
There are two types of cell division: Mitosis and Meiosis.
Mitosis is called a multiplication division; in other words, the cells multiply by dividing.
Meiosis is called a reduction division, because the cells do not multiply in this case, but retains a constant number.
Meiosis occurs in reproductive organ cells, while mitosis occurs in every other cell.
In bones for instance, as cell division occurs, the bone lengthens, leading to a visible increase in height. Substances are deposited in the bone which makes it stronger. This process is known as ossification.
Cell growth and maturation
As cells are formed, they grow subsequently, and then die, so that new ones can be formed.
Cell growth involves the increase in the size of cells and their adaptability to many functions.
In red blood cells (erythrocytes) for instance, the cells continue to increase in size, haemoglobin is formed, and other cell organelles disappear.
After its life span of 120 days, it is destroyed in the spleen.
Ageing simply means growing older. It is a natural part of the growth that presents with loss of hair, weakness of bones, wrinkling and folding of skin, etc.
Some of the factors responsible for ageing include:
Over time, the body cells continue to wear off as age sets in. Some processes no longer occur as smoothly as they used to.
As we age, the cells in our bodies get to a point where division ceases and then breakdown begins.
For instance, as one grows older, fat cells in the body begin to atrophy (reduce). These fat cells are responsible for the smooth texture of the skin. As these fat cells atrophy, the skin begins to fold, and wrinkles begin to appear.
The effect of age may be more visible in some individuals than in others. While some people will grow white hair earlier in life, some will happen later in life.
Someone who already has an eye defect in his/ her earlier years of life is more prone to have a declining sight when they grow older.
3. Environmental factors
Environmental factors include food, water, and surroundings.
People, who eat unhealthy foods more often, age faster.
Exposure to sun rays is another feature that enhances ageing. UV ray from the sun can lead to mutations, hence bringing the onset of ageing closer.
4. Health status
Some diseases like cancer make people look older; because it alters many normal functions in the body. Autoimmune diseases destroy cells of the body more quickly, leading to loss of weight and more changes that come with the advancement in age.
Kukua na kuzeeka - Mchakato wa ukuaji wa mwili unaendelea kwa sababu ya mabadiliko ya mwili. Kuanzia zygote hadi kiinitete, hadi mtoto mchanga, mtoto mchanga, kijana, na mtu mzima, ukuzi hutukia kwa utaratibu. Kamusi ya Merriam Webster hufafanua ukuzi kuwa ongezeko la asili la ukubwa. Ukuaji wa binadamu huonekana wakati urefu na uzito unaongezeka, na wakati wanaanza kupata uwezo wa kufanya shughuli mbalimbali kwa muda. Ukiendelea kukua kwa njia ya kawaida na kwa wakati unaofaa, unakuwa na wasiwasi. Ukuzi huchochewa na mabadiliko katika mahitaji ya sehemu mbalimbali za mwili. Kwa mfano, katika wiki ya tatu ya maisha ya kiinitete, mfumo wa moyo na mishipa ya damu huanza kukua na kuendeleza kwa sababu kiinitete hakiwezi tena kukidhi mahitaji yake ya oksijeni na lishe kwa kuenea tu. Hii ni ishara ambayo husababisha ukuaji na maendeleo ya moyo na vipengele vyake. Kadiri wakati unavyopita, mahitaji ya mwili huendelea kubadilika, na hivyo kukua na kukomaa. Mtoto anapozaliwa, anahitaji maziwa ya mama kwa miezi sita ya kwanza ya maisha yake nje ya tumbo la mama. Katika kipindi hicho, maziwa ya mama yanaweza kutoa virutubisho vya kutosha. Baada ya miezi sita, chakula cha ziada kinakuwa muhimu na mwili hujipatanisha na hii kwa kufanya mfumo wa kumeng'enya chakula kuwa mzuri wa kutosha kuvunja chakula. Kabla ya mwisho wa miezi sita, jaribio lolote la kutoa vyakula vingine litasababisha matatizo ya kumeng'enya chakula. Mchakato wa msingi unaofanyika wakati wa ukuaji ni: Chembe ni kitengo kidogo zaidi cha mwili. Wakati chembe zinapogawanyika, hilo husababisha ongezeko la idadi ya chembe. Ongezeko hilo husababisha sehemu za mwili kukomaa hatua kwa hatua. Kuna aina mbili za mgawanyiko wa chembe: Mitosis na Meiosis. Mitosis huitwa mgawanyiko wa kuzidisha; kwa maneno mengine, chembe huongezeka kwa kugawanyika. Meiosis inaitwa mgawanyiko wa kupunguzwa, kwa sababu seli hazizidi katika kesi hii, lakini huhifadhi idadi ya mara kwa mara. Meiosis hutokea katika chembe za viungo vya uzazi, huku mitosis ikitokea katika chembe nyingine zote. Kwa mfano, mifupa inapojigawanyika, mfupa huongezeka urefu, na hivyo urefu huongezeka. Vitu huhifadhiwa ndani ya mfupa ambavyo huifanya iwe na nguvu zaidi. Utaratibu huo huitwa ossification. Kukua kwa chembe na kukomaa Chembe zinapoundwa, zinaendelea kukua na kisha kufa ili chembe mpya ziweze kufanyizwa. Ukuzi wa chembe huhusisha ongezeko la ukubwa wa chembe na uwezo wao wa kuzoea kazi nyingi. Kwa mfano, katika chembe nyekundu za damu (erythrocytes), chembe hizo huendelea kuongezeka ukubwa, hemoglobini hufanyizwa, na chembe nyingine za chembe zinapotea. Baada ya siku 120 za maisha, huangamizwa katika utumbo. Kuzeeka humaanisha tu kuzeeka. Ni sehemu ya asili ya ukuaji ambayo huonyesha kupoteza nywele, udhaifu wa mifupa, makunyanzi na folding ya ngozi, nk. Vitu vinavyofanya mwili uzeeke ni hivi: Kwa muda, chembe za mwili huendelea kuharibika kadiri umri unavyopita. Baadhi ya taratibu hizo hazifanyi kazi kwa urahisi kama zilivyokuwa zamani. Kadiri tunavyozeeka, seli katika mwili wetu hufikia hatua ambapo kugawanyika kunakoma na kisha uharibifu huanza. Kwa mfano, mtu anapozeeka, chembe za mafuta mwilini huanza kupungua. Chembe hizo za mafuta husababisha ngozi iwe laini. Chembe hizo za mafuta zinapopungua, ngozi huanza kukunjika-kunjika, na makunyanzi huanza kuonekana. Athari za umri zaweza kuonekana zaidi kwa watu fulani kuliko kwa wengine. Wakati baadhi ya watu kukua nywele nyeupe mapema katika maisha, baadhi ya kutokea baadaye katika maisha. Mtu ambaye tayari ana kasoro ya jicho katika miaka yake ya mapema ya maisha ni zaidi ya kuathiriwa na kuona wakati wao kukua. 3. Uwe na mtazamo wa kweli Sababu za mazingira Sababu za mazingira zinatia ndani chakula, maji, na mazingira. Watu wanaokula vyakula visivyo na afya mara nyingi zaidi, huzeeka haraka. Kuathiriwa na miale ya jua ni jambo jingine linalofanya mtu akaze. Mionzi ya jua ya UV inaweza kusababisha mabadiliko ya chembe za urithi, na hivyo kusababisha mwanzo wa kuzeeka. 4. Uwe na uhakika Baadhi ya magonjwa kama vile kansa hufanya watu waonekane wazee; kwa sababu hubadilisha kazi nyingi za kawaida mwilini. Magonjwa ya autoimmune huangamiza seli za mwili haraka zaidi, na kusababisha kupoteza uzito na mabadiliko zaidi yanayokuja na umri.