Endocrine System (3.5)

Endocrine system

consists of a series of glands that produce chemical substances known as hormones

Hormones

chemical messengers that must bind to a receptor in order to send their signal

Neurotransmitters vs Hormones

Neurotransmitters are released in close proximity to cells with their receptors & have localized effects

Hormones are secreted into the bloodstream and travel throughout the body & have widespread effects

Hormones are __ to take effect, and tend to be __.

Slower; longer-lasting

What controls hormones?

The hypothalamus (CNS) and pituitary gland (endocrine system)

Pituitary gland location

descends from the hypothalamus at the base of the brain

What is the “master gland” of the endocrine system?

The pituitary gland

Why is the pituitary gland the master gland?

because its messenger hormones control all the other glands in the endocrine system, although it mostly carries out instructions from the hypothalamus

What does the pituitary gland secrete?

Messenger hormones

Growth hormones

Endorphins for pain relief

Other hormones that regulate fluid levels

Thyroid location

the neck

What does the thyroid gland secrete?

Growth hormones

Metabolism

Appetite

Hyperthyroidism

the thyroid secretes too much of the hormone thyroxine, causing agitation, bulging eyes, and weight loss.

What is one cause of hyperthyroidism?

Graves' disease — body attacks itself

Hypothyroidism

reduced hormone levels cause sufferers to experience tiredness, and they often complain of feeling cold

Adrenal glands location

atop the kidneys

What hormones do the adrenal glands secrete?

hormones involved in the stress response, such as epinephrine (adrenaline) and norepinephrine (noradrenaline).

What does the pancreas secrete?

hormones that regulate blood sugar levels: insulin and glucagon.

What is the pancreas essential for?

maintaining stable levels of blood sugar throughout the day by lowering blood glucose levels (insulin) or raising them (glucagon)

People who suffer from diabetes don’t produce enough ___

insulin

What do the gonads secrete?

Sexual hormones

What do the gonads mediate?

Sexual motivation and behavior

Male gonads

testes

Female gonads

ovaries

What do the ovaries secrete?

estrogens and progresterone

What do the testes secrete?

Androgens and testosterone