Cell specialization occurs a. with prokaryotes only b. to allow different groups of cells to perform a task c. in order for cells to communicate d. with single celled organisms

the animal that would be cutest if scaled down to the size of a cat? elephant

the menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.