Answer:
Many scientists use dichotomous keys to identify plants, animals, and other organisms. They may also use dichotomous keys to identify species, or to determine whether a particular organism has been identified and described before. However, dichotomous keys are not used only to identify organisms.
Answer:
Because natural selection selects for it. Thus it persists.
Explanation:
You have to understand heterozygote advantage. Basically, it's where heterozygotes have an advantage over homozygotes. In the case of sickle cell disease, heterozygotes have an advantage, and natural selection favors whatever is advantageous. Thus, because heterozygotes each have one recessive sickle-cell allele, as natural selection favors the heterozygotes, the recessive sickle-cell allele persists and remains in the gene pool.
The answer to the question above is a cell.
<span>Chlorophyll is any of many closely related green pigments found in cyanobacteria and the chloroplasts of algae and plants, and the function of it is that is absorbs energy from light.</span>