AP BIOLOGY

Detailed explanation-1: -Step 3: Therefore, there would be 40 chromosomes in the sperm cells of the same species.

Detailed explanation-2: -If an organism has 20 chromosomes, then the number of chromosomes the daughter cells have after mitosis is 20 because when a cell divides by the process of mitosis it produces two clone daughter cells having the same number of chromosomes (20) as the parent cell has.

Detailed explanation-3: -When the sperm and egg cells unite at conception, each contributes 23 chromosomes so the resulting embryo will have the usual 46. Meiosis also allows genetic variation through a process of gene shuffling while the cells are dividing.

Detailed explanation-4: -Of the 23 chromosomes in human spermatozoa, chromosomes 13, 18, 21, X, and Y are important because higher incidence of abnormalities in these chromosomes can to lead miscarriages or live births (Pang et al., 1999, 2005, 2010; Rubio et al., 2001).

Detailed explanation-5: -This division is an important event since after fertilisation haploid chromosomes from each gamete (male and female) fuse to retain the diploid state in the zygote. Diploid means two sets of chromosome and haploid is one set. Since here the diploid set is 16 thus one set will be half it, i.e, 8.