Anatomy and Physiology: Endocrine System

Exocrine glands

Exocrine glands

secrete substances into ducts that lead to targeted tissues

Endocrine glands

secrete substances directly into the bloodstream

Endocrine system

Consists of a group of ductless endocrine glands that secrete substances called hormones directly into the bloodstream

Hormones

Chemical substances produced and secreted by the endocrine glands

Pituitary Gland

Often called the “master gland” of the body because it produces many hormones that affect other glands

Acromegaly

results from an oversecretion of somatotropin in an adult

Gigantism

a rare disorder resulting from an oversecretion of somatotropin before puberty

Diabetes insipidus

caused by decreased secretion ofvasopressin

Dwarfism

results from an undersecretion of somatotropin

Thyroid Gland

synthesizes hormones that regulate the body’s metabolism and control the level of calcium in the blood

Goiter

an enlargement of the thyroid gland

Hyperthyroidism

an overactivity of the thyroid gland

Grave’s disease

a severe form of hyperthyroidism

Hypothryroidism

an underactivity of the thyroid gland and a deficiency of thyroid hormones

Parathyroid gland

four small glands located behind and attached to the thyroid gland; regulate the amount of calcium in blood

Hyperparathyroidism

an overactivity of the parathyroid gland

Pypoparathyroidism

an underactivity of the parathyroid gland

Adrenal Glands

frequently called the suprarenal glands because one is located above each kidney

Addison’s disease

caused by decreased secreation of aldosterone on the part of the adrenal cortex

Cushing’s syndrome

results from an oversecretion of glucocorticoids on the part of the adrenal cortex

Pancreas

a fish-shaped organ located behind the stomach

Diabetes mellitus

a chronic disease caused by decreased secretion of insulin or by body cells resistant to the effect of insulin

Ovaries

sex glands of the female

Testes

male sex glands

Thymus

located in the upper part of the chest under the sternum; contains lymphoid tissue

Pineal body

small structure attached to the roof of the third ventricle in the brain; knowledge of its physiology is limited

Placenta

A temporary endocrine gland produced during pregnancy; acts as a link between mother and infant; provides nutrition and promotes lactation