Answer:
Sexual reproduction results in genetic variation and asexual reproduction does not.
Explanation:
The key difference between sexual and asexual reproduction is that sexual reproduction occurs between two parents while asexual reproduction occurs via a single parent. Asexual reproduction requires only a single divisible cell to produce a new organism, whereas sexual reproduction requires two gametes, their formation and fusion.
Distribution of phenotypes within a population may be impacted by different types of natural selection. These types of selection include;
Directional selection involves a change in the environment shifts of phenotypes observed. Example is the giraffe neck-length, where the length got longer and longer over time to reach the leaves at the top of trees.
Stabilizing selection , this is a selection where an average phenotype is favored. example is number of eggs laid by birds such that too many eggs will be a waste of energy because some chicks would starve.
Disruptive selection is a selection where individuals with an average value of a trait are affected most while those with values below average are affected least. Example small individuals are capable of hiding from predators while big individuals can not fit in the hiding place but instead will fight with predators.
Pangea was the supercontinent that had all the landmasses of earth together before the Triassic period and that broke up into Laurasia and Gondwanan. However, Panthalassa is a prehistoric ocean that was surrounding Pangea.
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Human chorionic gonadotropin (hCG) is secrete by the embryo early in pregnancy to keep the corpus luteum for dying. This positive feedback will maintain the corpus luteum, which secretes Progesterone and Estrogens throughout pregnancy, in order to keep the endometrium well to nourish the embryo/fetus.
In adults, stem cells remain undifferentiated until they are needed to repair or replace other cells. Stem cells can produce cells that are identical to themselves.
