Which determines the reactivity of an alkali metal? A) its boiling and melting points
B) the shininess of its surface
C) the number of protons it has
D) its ability to lose electrons

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.

1. is geographic distribution

2 is increasing complexity

3 is transitional forms