Directional selection acts against:
both extremes simultaneously in the variation of the trait
one of the extremes in variation
the average or mean value for the population
none of these

Pl as time goes by and water goes through the water cycle again and again, the amount of water on earth: increases decreases ostays the same goes up and down

1. -define adaptation2 explain darwin's theories of descent with modification and natural selection in detail3. -explain how each of these provides evidence for evolution: a. -fossil record, including superposition and transitional fossilsb-anatomy, including homologous structuresc-biological molecules, including dna and proteins4. -explain the difference between convergent and divergent evolution.5. -define and give three examples of artificial selection6. -define and give one example of coevolution.7. -explain biodiversity and how it benefits humans.8. -explain a type of population lest affected by environmental change.

What are the four stages of cell signaling?