The heliocentric system gained support when Galileo observed that

Venus goes through phases similar to those of Earth's moon. Hope this helps out.

Explanation:

b.have there own function.

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.