There are prerequisites for natural selection to take place. Can you identify them? Check all that are correct.

What are the prerequisites for natural selection to take place?

1. In a given population genetic variation must exist.

2. Variations within a population are always the result of DNA mutations.

3. In a given population, more offspring are produced than can survive.

4. Reproduction within a population is differential.

5. In any population natural selection can only occur if there is sexual reproduction.

6. Inherited traits that provide an advantage will lead to death and possible extinction.

Is this USA Test prep?

I believe that it is all except the 2nd one

Explanation:

I took the test. 1. in a given population variation must exist. 3. in a given population, more offersprings are produced than can survive. 4. reproduction within a population is differential.

(if you know the answer was wrong please put the correct answer under the comment ^^)

an adaptation is a change or process by which an organism takes to be better suited for its environment. for example; migration is a behavioral adaptation, this is needed because birds are not built to last extremely cold climates. there are different adaptations because there are different species needing to adjust to different things, bears don't migrate; they hibernate.

answer: - b cells

explanation: -

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.