Examples of exocrine glands include the sweat glands, salivary glands, mammary glands, the pancreas, and the liver.

There are two major classifications of glands: endocrine glands and exocrine glands.

These glands are composed of the adrenal cortex and the adrenal medulla.

Adrenal glands are located on top of the kidneys.The adrenal glands consist of an outer adrenal cortex and an inner adrenal medulla, which secrete different hormones.Adrenal glands are a pair of ductless glands located above the kidneys.Adrenal glands are composed of the adrenal cortex and medulla both produce hormones that control essential body functions and responses.The endocrine systems found in the head and neck include the hypothalamus, pineal, pituitary and thyroid glands.The major endocrine glands include the pituitary, pineal, ovaries, testes, thyroid, hypothalamus and adrenal glands, additionally other tissues such as the kidney and liver also display secondary adrenal functions.The endocrine system is in contrast to the exocrine system, which features ducted glands that secrete substances onto an epithelial surface for example, a sweat gland.For example, the pineal gland, located at the base of the brain, secretes the hormone melatonin, responsible for regulating sleep patterns.The endocrine system is a system of ductless glands that secrete hormones-chemical messengers that are carried for long distances.The adrenal medulla sits below the three layers of the adrenal cortex and is innervated by nerve fibers.The adrenal medulla secretes approximately 20% noradrenaline (norepinephrine) and 80% adrenaline (epinephrine).The adrenal medulla is responsible for the production of catecholamines, derived from the amino acid tyrosine.The adrenal medulla is the core of the adrenal glands, and is surrounded by the adrenal cortex.The adrenal cortex is devoted to the synthesis of corticosteroid and androgen hormones.

Evaluate the types of adrenal insufficiency that lead to adrenal gland disorders.An example of second adrenal insufficiency syndrome can be caused by craniopharyngioma which is a benign tumor that can damage the pituitary gland causing the adrenal glands not to function.Other cases are due to congenital adrenal hyperplasia or an adenoma (tumor) of the adrenal gland.Primary adrenal insufficiency is due to impairment of the adrenal glands.The adrenal glands are triangular-shaped organs on top of the kidneys.Each adrenal gland has two distinct structures, the outer adrenal cortex and the inner medulla-both produce hormones.In humans, the right adrenal gland is triangular shaped, while the left adrenal gland is semilunar shaped.

In mammals, the adrenal glands (also known as the suprarenal glands) are endocrine glands that sit atop the kidneys.Examples of adrenal gland in the following topics:

Definition of adrenal gland