Rock is considered an ecosystem because based on the definition of ecosystem. A rock is happens to be in our environment which makes it part of our ecosystem. 1 person found this useful.
The parathyroid glands are four tiny glands, located in the neck, that control the body's calcium levels. Each gland is about the size of a grain of rice (weighs approximately 30 milligrams and is 3-4 millimeters in diameter). The parathyroids produce a hormone called parathyroid hormone (PTH). PTHPTH - parathyroid hormone raises the blood calcium level by: breaking down the bone (where most of the body's calcium is stored) and causing calcium release. increasing the body's ability to absorb calcium from food.
hormone-producing glands throughout the body include the adrenal glands, which primarily. produce cortisol; the gonads (i.e., ovaries and testes), which produce sex hormones; the. thyroid, which produces thyroid hormone; the parathyroid, which produces parathyroid.