What is the main function of the cell membrane in all cells

Regulate the movement of materials in and out of the cell

Explanation:

The cell membrane of animal cells is a thin membrane that lines the entire cell surface, and it is a selectively permeable membrane, thus, allowing the entry of useful materials into the cell and exit of waste products out of the cell.

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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