Answer::: Brain structures called the hypothalamus and pituitary gland control the menstrual cycle. The hypothalamus triggers the pituitary gland to make hormones that trigger the ovaries to make oestrogen and progesterone. ... Disorders of the hypothalamus, pituitary gland or ovaries can affect menstruation, causing amenorrhoea
Answer:
these differentiate as a result of signaling mechanisms. ... The daughter cells divides and after each division it becomes more specialized. When it reaches a mature cell type downstream (for example, becomes a red blood cell) it will no longer divide.
Answer:
D
Explanation:
because it shows yearly rainfall and the desert can't get rain
