C, because alleles are alternative forms of a gene that arise from mutation.
Answer:
well B the uterus walls shed away and come out in clots of blood.
a neurosecretory cell in the hypothalamus.
Answer: different organisms have different chromosome numbers
Explanation: eukaryote cells have more than one chromosome
chromosomes are present in most cells all the time (not in erythrocytes), but cannot be visualised except during telophase of mitosis or meisosis
bacterial cells don’t have a nucleus
It allows the scientist to determine the age of the rock it is in
