ascending signals in the spinal cord travel via gray matter, while descending signals travel via white matter.

Maria wanted to grow a fern in her backyard. acting on a suggestion from a friend, she collected brown dots from the underside of a fern's leaves and then potted them. after a few days, maria saw small fern leaves erupting from the pot. which statement explains this phenomenon? a. the fern transitioned from gametophyte generation to sporophyte generation. b. the fern grew as a result of mitosis. c. the fern transitioned from sporophyte generation to gametophyte generation. d. the fern grew to be genetically identical to its parent plant.

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

Which muscle is responsible for inhalation ?