Answer:
Sexual Reproduction. ... Organisms that reproduce sexually by joining gametes, a process known as fertilization, must have a mechanism to produce haploid gametes. This mechanism is meiosis, a type of cell division that halves the number of chromosomes. Meiosis occurs only in gamete producing cells within the gonads.
Explanation:
Secretion of human chorionic gonadotropin [HCG] only occur during pregnancy in the placenta. The concentration of this hormone increase rapidly during the first three months of pregnancy; the amount in the blood stream doubles every two to three days as the development of the placenta and embryo progress. The hormone reaches its maximum concentration peak around the sixth week of pregnancy and after this, its concentration decline.
How can reproductive isolation lead to speciation<span>? If populations cannot mate successfully with one another, genetic differences may accumulate in the populations. Over time they become very different and give rise to new species.</span>
Answer:
Photolysis of water takes place in inner membrane of thylakoid.
Hope it helps u.
Molecular evidence would include DNA
by comparing Gene sequence, you can tell which species have the most genes in common
