The stomach is the only part of the alimentary canal with three muscular layers. Why does the stomach need three layers of muscle

Dna and rna share a number of similarities, but they also differ in certain aspects of their structure. wich nitrogenous base is found in rna but is not found in dna

Examine the air pressure map. which type of line is shown on the map?

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.