1 The phenotype may change constantly throughout the life of an individual because of environmental changes and the physiological and morphological changes associated with aging.
What is parathyroid hormone? Parathyroid hormone is secreted from the four parathyroid glands, which are small glands in the neck, located behind the thyroid gland. Parathyroid hormone regulates calcium levels in the blood, largely by increasing the levels when they are too low.It does this through its actions on the kidneys, bones and intestine:hat is parathyroid hormone? Parathyroid hormone is secreted from the four parathyroid glands, which are small glands in the neck, located behind the thyroid gland. Parathyroid hormone regulates calcium levels in the blood, largely by increasing the levels when they are too low.
thyrotrophic hormone or thyroid stimulating hormone (TSH) a hormone secreted by the anterior lobe of the PITUITARY GLAND which triggers the shedding of THYROXINE from the colloidal follicles of the THYROID GLAND into the bloodstream. Excess thyroxine inhibits the production of TSH - an example of a negative FEEDBACK MECHANISM.