AP BIOLOGY

Detailed explanation-1: -Each sperm cell contains half the father’s DNA. But it’s not identical from sperm to sperm because each man is a mixture of the genetic material from his parents, and each time a slightly different assortment of that full DNA set gets divided to go into a sperm.

Detailed explanation-2: -Monozygotic (MZ) twins, also called identical twins, occur when a single egg cell is fertilized by a single sperm cell. The resulting zygote splits into two very early in development, leading to the formation of two separate embryos. MZ twins occur in 3 to 4 per 1, 000 births worldwide.

Detailed explanation-3: -Although all sperm may look the same to a casual observer in fact human ejaculates are very heterogeneous, and subpopulations of sperm with distinct biochemical and physiological characteristics can be identified in every sample.

Detailed explanation-4: -If two sperms fertilize an egg, things go wildly wrong, yielding a triploid offspring with 69 chromosomes with an extra set in addition to the normal maternal/paternal pair. An egg fertilized by three sperms receives two extra chromosome sets, resulting in a quadruploid individual with 92 chromosomes.