Answer:
The populations become adapted to different environments and eventually become so different that they cannot interbreed to produce fertile offspring.
Speciation is the evolution of one species into two different kinds, and when they become isolated, that is the final step, since they cannot interbreed any longer.
1 diploid cell (2n) cell becomes 4 haploid (n) germ cells (eggs or sperm). During meiosis, chromosomes are replicated once in S phase (just like mitosis), but the cell divides twice. ... The result: chromosomes after meiosis are genetically unique and have combinations of DNA derived from both parents.
In the hydrologic cycle, after water precipitates to the surface, it can return to the atmosphere by processes of evaporation.
Answer: C. Cancer
Explanation:
Current cancer immunotherapies mainly focus on CD8+ T cells. Given the heterogeneous nature of cancer, personalized cancer immunotherapy that integrates the power of both CD8+ T cells in adaptive immunity and NK cells in innate immunity might be the future direction, along with precision targeting and effective delivery of tumor-specific, memory CD8+ T cells and NK cells.