How does the circulatory system work at the organ level? Nutrients are delivered throughout the body.

Cardiac muscle contracts.

The heart pumps the blood.

Blood cells carry nutrients.

After fertilization, which type of cellular division is responsible for the growth and development of a complex, multicellular organism?

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

Ais a group of individuals of the same that exist together in the same place at the same time