The cell membrane
a.
converts glucose to other energy molecules.
b.
alters and packages proteins and lipids.
c.
is the site of most cellular chemical reactions.
d.
controls which substances enter and exit the cell.

Explanation:

controls which substances enter and exit the cell. hope it helped!

the speed increase from w to x due to increased gravity force

the speed decreases from x to y due to decrease in gravity

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

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