The thyroid gland and the adrenal glands are part of the body's endocrine system. According to Endocrine Web, the endocrine system is composed of a group of glands that secrete hormones. The thyroid gland is a butterfly-shaped organ that wraps around the front of the trachea at the base of the neck. The adrenal glands are two small, triangular glands, each sitting on top of each kidney.
Functions of the Adrenal Cortex
According to the University of Maryland Medical Center, the outer portion of the adrenal gland is known as the adrenal cortex. This part of the adrenal gland is responsible for secreting hormones that have an effect on the body's metabolism, on chemicals in the blood and on certain body characteristics. The hormones secreted by the adrenal cortex are the corticosteroid hormones, the aldosterone hormones and the androgen hormones. The corticosteroids control the body's use of fats, proteins and carbohydrates and also affects the functioning of the immune system. The aldosterone hormone inhibits the level of sodium excreted in the urine. This is an important factor in maintaining blood volume and blood pressure. The androgen hormones have a minimal effect on the development of male characteristics.
Functions of the Adrenal Medulla
The University of Maryland Medical Center reports that the inner part of the adrenal gland is known as the adrenal medulla. This part of the adrenal gland helps in coping with physical and emotional stress. The adrenal medulla secretes the hormones epinephrine and norepinephrine. Epinephrine, also called adrenaline, is the hormone that causes the heart to race, facilitates blood flow to the muscles and brain, causes relaxation of smooth muscles and helps convert glycogen to glucose in the liver. Norepinephrine is the hormone that increases blood pressure.
Functions of the Thyroid
According to Endocrine Web, the function of the thyroid is to take iodine and convert it into the thyroid hormones trilodothyronine (T3) and thyroxine (T4). T3 and T4 are then released into the bloodstream and carried throughout the body where they control metabolism. The University of Maryland Medical Center defines metabolism as the chemical activity that occurs in cells, releasing energy from nutrients or using energy to create other substances like protein.
