Answer:
The correct answer is option A. "directional selection".
Explanation:
Directional selection is a type of natural selection at which traits with extreme characteristics are selected over traits with medium characteristics. In this case, a long-term climatic change resulted in all seeds that are the fountain of food for finch becoming hard. This will result in a directional selection on bill size in the finch population, where large-billed birds will be selected over small and medium-billed birds.
Answer:
In the politics of representative democracies, a political machine is a political group in which an authoritative leader or small group command the support of a corps of supporters and businesses, who receive rewards for their efforts.
Explanation:
Answer:
b. They are produced by memory B cells
Explanation:
The rapid cell division in activated B cells is followed by the differentiation of daughter cells into the plasma cells. The plasma cells are the precursor for antibodies and memory B cells. The antibodies kill the antigens while memory B cells are long-lived cells.
Hence, antibodies are not produced by memory B cells but by plasma cells.
Answer:
La Tierra primitiva no tenía una atmósfera o agua libre. El planeta estaba demasiado caliente para que los gases y el agua se acumularan.
Explanation:
Your nervous system quickly responds to the threat and sends a signal to your brain which causes your muscles/ body to react.
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