How is the single cell that all humans are originated from formed?
when the egg and sperm unite (zygote)
What is zygote?
when the egg and sperm unite
What happens at Youth before birth?
before birth, the fetus develops all the organs and systems necessary for a functional body
What happens at Youth after birth?
after birth, the infrant continues to mature and cells divide for growth.
What happens at youth by adulthood?
cell division reduces to only occur during repear of tissues
What happens with Aging?
losing tissue mass due to cell greatly decrease division rate and dead cells are replaced at a slower rate, tissue is lost, 7 weakening occurs.
What are the 4 theories of aging?
free radical, mitochondrial, genetic, telomeres
What is the free radical of aging?
molecules (primarily oxygen) that have an unpaired electron and are highly reactive. They build up and damage the cells. (Vit E & C are used to reduce radicals and thus reduce cell damage)
What is the mitochondrial theory of aging?
the mitochondria produces free radicals as a result of cellular respiration due to high metabolism. Those that eat less or have a slow metabolism live longer because less radicals are produced by the mitochondria.
What is the genetic theory of aging?
our genes have a predetermined life span for cells. This means that it is genetically predetermined how many times a cell divides and how long it will live. This indicates that aging is a normal part of human development.
What is the telomeres of aging?
sections of DNA that do not contain genes, but influence the amount of times a cell divides. As the cells divide, the number of telomeres decreases, thus the cell will divide less often.