A. umbilical cord is the answer
Answet is D
species come under at a very low level of the classifieds
Answer:I think it is part B
Explanation:
Answer:
6==. During spermatogenesis, four sperm result from each primary spermatocyte, which divides into two haploid secondary spermatocytes; these cells will go through a second meiotic division to produce four spermatids