The sa node acts as the pacemaker of the heart because these cells are

Next pretest: evolution select the correct answer in a laboratory population of flies, the female flies are gray and the males are yellowish gray. biologists observed that all the male flies had an equal chance for reproduction, but the male flies with the brightest colors were more likely to successfully reproduce. what phenomenon could explain such a change? a sexual selection b. disruptive selection c. stabilizing selection d. directional selection

Buuy which of the following did you include in your response? organs perform specific functions in the body to keep it alive. organelles perform specific functions in cells to keep them alive. done

Number and variety of living organisms includes genetic, species, and ecological types