There are three muscles located in the anterior compartment of the upper arm â biceps brachii, coracobrachialis and brachialis. They are all innervated by the musculocutaneous nerve. A good memory aid for this is BBC â biceps, brachialis, coracobrachialis.
Calcitonin is a hormone secreted by the thyroid gland that reduces the concentration of blood calcium level when it has risen to an above normal level. This polypeptide hormone is made up of 32 amino acids and is produced mainly by the parafollicular cells (also known as C cells) of the thyroid gland.
A more technical description is given below: Three hormones act in the body to increase blood calcium levels to normal. These hormones are 1,25-Dihydroxycholecalciferol, parathyroid hormone (PTH), and calcitonin that originate respectively from the liver and kidneys, parathyroid glands, and thyroid glands.he second, PTH, dissolves bone into the blood. The third, calcitonin, prevents the bone-derived calcium from being resorbed (reabsorbed) into the bone from which it came via PTH. To summarize, these three hormones act in concert to raise calcium levels via external and internal routes.