Trisomy 21 is a genetic condition in which 21 chromosome fail to separate during the growth of egg cell and sperm which make either of the two to an extra copy of chromosome 21. This is also known as down syndrome. This lead to slow and in appropriate mental development in affected individual.
Phosphoriboglycinamide transformylase(GART) is agene found on chromosome 21, which lead to down syndrome is an example of trisomy 21.
The Golgi apparatus is located in the cells. It is an extra combination of organelle similar to the ER. This was named following Camillo Golgi. (Notice that his last name is Golgi)
Explanation: the ice age posed a new chalenge to deer mice and on the ice the preadators could spot the darker deer mice better than the light deer mice.
