Download The Human Endocrine System: The Glands and Their Hormones

The Human Endocrine System: The Glands and Their Hormones
Anterior Pituitary:
 Follicle-stimulating hormone (FSH) – produces eggs in females and sperm in males
 Luteinizing hormone (LH) – stimulates the ovaries to release eggs and stimulates the testes to release
sperm
 Thyroid-stimulating hormone (TSH) – stimulates the thyroid to release thyroxine
 Adreno-corticotropic hormone (ACTH) – stimulates the release of hormones from the adrenal glands
 Growth hormone (GH) – indirectly controls the growth of bone and cartilage
 Melanocyte-stimulating hormone (MSH) – stimulates the production of the skin pigment, melanin
 Prolactin – stimulates secretion of milk from the mammary glands after a female gives birth
Posterior Pituitary:
 Antidiuretic hormone (ADH) – makes the kidneys reabsorb water
 Oxytocin – stimulates contractions of the uterus in childbirth
Thyroid:
 Thyroxine – iodine-containing hormone that regulates the rate of metabolism
 Calcitonin – regulates blood calcium levels
Parathyroid glands:
 Parathyroid hormone – produced by the parathyroid glands; regulates calcium and phosphate
metabolism
Adrenal medulla:
 Epinephrine – also known as adrenalin; helps the body deal with stress by increasing metabolic
activities; used in the “fight or flight” response (in times of emergency)
 Norepinephrine – also known as noradrenalin; helps the body deal with stress; used in the “fight or
flight” response
Adrenal cortex:
 Aldosterone – regulates sodium absorption and potassium secretion
 Cortisol – helps regulate metabolism
Pancreas:
 Insulin – lowers blood glucose levels
 Glucagon – increases blood glucose levels; stimulates release of sugar from the liver
Ovaries:
 Estrogen – stimulates development of the female reproductive system
 Progesterone – regulates the menstrual cycle
Testosterone:
 Testosterone – stimulates development of the male reproductive system
Thymus:
 Thymosin – stimulates development of T cells throughout childhood
Pineal gland:
 Melatonin – produced by the pineal gland; controls sleep-wake cycles
Location of Glands: (be able to label all 10 glands)
Things to Know:
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Endocrine system – involves the production of regulatory chemicals (hormones) by glands
Hormones – chemical messages produced by glands, released directly into the bloodstream to work
somewhere else in the body; they are specific (specific shape) which means they only work with specific
receptors on target cells
Glands – organs that produce and release chemical secretions.
Exocrine glands – release secretions through tubes or ducts, directly to the organs that use them.
Examples: gallbladder, pancreas.
Endocrine glands – release hormones into the bloodstream
Communication – the body’s cells communicate through the electrochemical messages of the nervous
system (neurotransmitters) and chemical messages of the endocrine system (hormones)
Feedback mechanisms – help maintain homeostasis (like a thermostat)
Negative feedback example – blood sugar levels increase after eating cake, which makes insulin levels
rise in order to lower the blood sugar levels back to normal (like a thermostat)
Positive feedback example – labor contractions begin and strengthen over time, continuously, until the
baby is born
Hypothalamus – a region of the brain that connects the nervous system with the endocrine system; it
controls secretions of the pituitary
Pituitary gland – known as the master gland
Prostaglandins – local hormones that only affect nearby cells
Ovaries and pituitary – regulate the menstrual cycle
Estrogen and progesterone – influence uterus during pregnancy
Two Models of Hormone Action
One Messenger Model (steroid hormones):
Two Messenger Model (non-steroid hormones):
Glandular Disorders
Hormone and Gland
Growth hormone
(anterior pituitary)
Thyroxine
(thyroid)
Parathyroid hormone
(parathyroids)
Aldosterone, cortisol
(adrenal cortex)
Insulin
(pancreas, beta cells)
Glucagon
(pancreas, alpha cells)
Oversecretion (hypersecretion)
Giantism in children
Acromegaly in adults – abnormally large
hands, feet, and enlarged facial structures
Hyperthyroidism – weight loss,
nervousness, insomnia, protruding eyes,
often accompanied by a goiter (enlarged
thyroid)
Undersecretion (hyposecretion)
Dwarfism in children
Removal of calcium from bones, making
them brittle and causing them to break
easily
Cushing’s disease – excess fat deposits,
puffy face, excess facial hair, high blood
glucose levels, decreased immunity
Low blood calcium levels causes tetany,
making skeletal muscles contract violently
Diabetic shock – blood glucose levels
drop dangerously low and convulsions,
unconsciousness (and death) could occur
Abnormally high blood glucose levels
(like with diabetes)
Cretinism in infants – dwarfism with out
of proportion body parts
Hypothyroidism in adults – weight gain,
sluggishness, slower metabolism
Addison’s disease – weight loss, reduced
tolerance to stress, irregular blood glucose
levels, weakness, increased skin
pigmentation
Diabetes – abnormally high blood glucose
levels, dehydration, weight loss
Hypoglycemia – abnormally low blood
glucose levels