Answer:
interphase
Explanation:
During interphase, the cell grows and the DNA replicates. After that there's the mitotic phase where the replicated DNA and the contents in the cytoplasm are sperated in a way that the cell divides.
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.
1.Biological species concept
2.Cladistic species concept
3.Cohesion species concept
4.Competition species concept
5.Ecological species concept
6.Evolutionary species concept
7.Isolation species concept
8.Phenetic species concept
9.Phylogenetic species concept
10.Recognition species concept
11.Typological species concept
For descriptions just look them up :)