Exocrine Glands are those which release their cellular secretions through a duct which empties to the outside or
into the lumen (empty internal space) of an organ. These include certain sweat glands, salivary and pancreatic glands,
and mammary glands. They are not considered a part of the endocrine system.
Endocrine Glands are those glands which have no duct and release their secretions directly into the intercellular
fluid or into the blood. The collection of endocrine glands makes up the endocrine system.
The main endocrine glands are the pituitary (anterior and posterior lobes), thyroid, parathyroid,
adrenal (cortex and medulla), pancreas and gonads.
The pituitary gland is attached to the hypothalamus of the lower forebrain.
The thyroid gland consists of two lateral masses, connected by a cross bridge, that are attached to the
trachea. They are slightly inferior to the larynx.
The parathyroid glands are four masses of tissue, two embedded posterior in each lateral mass of the
thyroid gland.
One adrenal gland is located on top of each kidney.
The cortex is the outer layer of the adrenal gland. The ,medulla is the inner core.
The pancreas is along the lower curvature
of the stomach, close to where it meets the first region
of the small intestine, the duodenum.
The gonads are found in the pelvic cavity.
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