According to the International Union for Conservation of Nature (IUCN) giraffe numbers across the continent of Africa fell 40% b
etween 1985 and 2015. The main threats to the giraffe population include a shrinking habit, conflict, and poaching. Checking the data, we see that while four subspecies have declining populations, four subspecies have growing populations. This is a modern-day example of natural selection at work. What elements of natural selection are at work here? A) Environmental conditions reduce the population numbers; only the fittest subspecies are able to survive. B) Overpopulation exists in a shrinking habitat; some subspecies decline in number; differential reproduction occurs. C) The death rate of some subspecies is elevated due to conflict and poaching; death is random; differential reproduction occurs. D) Genetic variation exists in the giraffe population across Africa; only those animals with a specific gene pool, represented by certain subspecies, can survive. Eliminate
The most appropriate statement about healing wounds from the choices given is "cell growth increases both toward the beginning and the end of the healing process." The correct answer is A.
Enzymes are involved in most of the chemical reactions that take place in organisms. About 4,000 such reactions are known to be catalyzed by enzymes, but the number may be even higher.
