How long do you have to exercise to notice cardiovascular changes?

What does the hardy-weinberg principle relate to? a. chances of survival of an organism b. frequency of alleles in a population c. natural selection in a species d. causes of evolution among organisms

Both male and female gametes are created during the process of meiosis. the formation of male gametes is called spermatogenesis. after telophase il of spermatogenesis, there would be are all genetically male gametes created that

Abird flies by moving its wings up and down. which two systems are most directly responsible for the movement of a bird's wings? a. skeletal and muscular systems b. respiratory and muscular systems c. skeletal and digestive systems d. respiratory and digestive systems