Once you finish
growing to adulthood, neurons stop dividing. Hair follicle cells constantly
divide throughout your lifetime since they are constantly producing cells that
become part of the hair itself as they die. So in an adult, the rate of cell
division for neurons is zero (although there is some counter-evidence but it is
certainly very low) while the hair follicle rate is much higher on the order of
once every few days or faster.
This means that the mothers green eyes are recessive alleles and the fathers brown eyes are dominant alleles. The blue eyed puppy is blue eyed because there must have been a gene in the mothers or fathers past generation.
<span>Protein is made up of building blocks called amino acids</span>
The endoplasmic reticulum can either be smooth or rough, and in general its function is to produce proteins for the rest of the cell to function. The rough endoplasmic reticulum has on it ribosomes, which are small, round organelles whose function it is to make those proteins.