How does a substance cross the cell membrane in diffusion? a- flowing down the concentration gradient
b- binding to a carrier protein
c- going through a pump
d- going through a channel protein
(ck-12)

Under the soviet system, the government a. controlled all forms of communication. b. allowed newspapers to print whatever they wanted. c. controlled editorials but not the reporting of news. d. encouraged access to a wide variety of news sources. select the best answer from the choices provided a b c d

Brainliest ! which would require more force to move or slow down between a bowling ball and a soccer ball? explain why?

One of the reasons that stars are so large is because