Endocrine Glands Functions And Secretions
Endocrine glands are the ductless glands of the body that make or secrete hormones internally and pass them directly into the blood stream.
Endocrine glands
include the pineal, pituitary, thyroid, parathyroid, thymus, adrenal glands,
ovaries, testes, the placenta, pancreas, etc. The last-mentioned gland
(pancreas) has both internal and external secretions. It secretes pancreatic
juice that flows to join duct bile and enters the duodenum.
It also secretes two
other hormones- insulin and glucagon-directly into the blood. Insulin controls
the level of glucose (sugar) in the blood and glucagon causes an increase in
the blood sugar level and has an opposite effect to that of insulin, thus
maintaining the level of sugar in the blood. Glucagon is administered by
injection to counteract diabetic hypoglycaemia (a decreased level of glucose in
the blood stream causing muscular weakness, mental confusion, anxiety,
excitement, sweating, delirium, but in extreme cases it may lead to coma.
Hypoglycaemia occurs in diabetes mellitus due to the excessive or unwanted use
of insulin and from overdrugging to reduce the level of sugar in the blood.
Sometimes hypoglycaemia is also due to insufficient intake
of carbohydrate that contains sugar, carbon, hydrogen, nitrogen, starches and
cellulose (cellulose is an organic compound which is found in the outer walls
of plants and vegetables; cellulose serves as a dietary fibre and is not
digested by man, but supplies roughage for the stimulation of peristalsis - the
pushing movement of the intestines).