The adrenal glands may be lacking in the body, or be present excessively. Both cases are a risk.
The thyroid gland is a glandular structure. The thyroid glands are located above the breastbone between the clavicles, for in front of the trachea, below the skin.
Metabolism is the word that comes to expressing the vital processes of cells designed to keep all cell functions, such as reproduction, repair and actually keeping life in balance, also called homeostasis.