Circadian rhythms can best be described as heartbeats that trigger a change in blood circulation. the regulation of biological cycles into regular, daily patterns. the time between sunrise and sunset, which determines sleep patterns. the changes that occur in wakefulness after jet lag and shift work.

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.