Answer:
The skull protects the brain from any direct damage and the vertebrae helps keep the nerves in the spine in place and protected from damage. So the central nervous system is protected by the vertebrae and the skull.
The answer is; Thyroid hormones levels decrease, TRH levels increase, and PRL levels increase.
The thyroid gland is responsible for producing the growth hormone thyroid hormone. When the gland is reduced, then intuitively, the levels of thyroid hormone reduce in the body. This causes the hypothalamus to release thyroid releasing hormone (TRH) in an attempt to spur thyroid hormone production to normal levels. THR, in a domino effect, causes the pituitary to release higher levels prolactin (PRL).
A. the union of the egg and sperm
age, heredity diseases, environment
i can only think of 3 but hope these help