The Endocrine SystemThe other communication system in the body—is made up of endocrine glands that produce hormones, chemical substances released into the bloodstream to guide such processes as metabolism, growth, and sexual development.

Endocrine GlandsGlands of the endocrine system that release hormones into the bloodstream

HormonesChemical substances released by the endocrine glands; they help regulate bodily activities

The Endocrine System

Hormones

• Hormones interest psychologists for two reasons:

• First: At certain stages in our development hormones organize the nervous system and body tissue

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• Second: Hormones activate behaviors

Thyroid Gland

• Thyroid Gland• Endocrine gland located below the voice

box; it produces the hormone thyroxin.

• What it does:• Regulates the body’s rate of metabolism•

Parathyroid Glands• Parathyroids• Four tiny glands embedded in the

thyroid; they secrete parathormone

• What they do:• Control and balance the levels of

calcium and phosphate in the blood and tissue fluids

Pineal Gland

• Pineal Gland• A gland located roughly in the

center of the brain that appears to regulate activity levels over the course of a day

• What it does:• Appears to regulate activity by

controlling the release of melatonin

The Pancreas

• The Pancreas• Organ lying between the

stomach and small intestine

• What it does:• Secretes insulin and glucagon to

regulate blood-sugar levels

Pituitary Gland

• Pituitary Gland• Gland located on the underside

of the brain; it produces the largest number of the body’s hormones

• It has two parts that function separately:

- Posterior Pituitary- Anterior Pituitary

Posterior Pituitary

• Posterior Pituitary• Part of the pituitary that

affects thirst, sexual behavior, and perhaps maternal behavior

Anterior Pituitary

• Anterior Pituitary• Part of the pituitary known as

the “master gland” because it produces numerous hormones that trigger the action of other glands

• What it does:• Regulates body growth and also

affects motivation and emotions

Gonads • The Gonads• The reproductive glands- testes in

males and ovaries in females.

• What they do:• They play a number of important

organizing roles in human development

Adrenal Glands

• Adrenal Glands• Two endocrine glands located just

above the kidneys. Each adrenal gland has two parts:

• - Adrenal cortex

• - Adrenal medulla

Adrenal Cortex

• Adrenal Cortex• Outer covering of the two adrenal

glands; the adrenal cortex releases hormones important for dealing with stress

Adrenal medulla

• Adrenal Medulla• Inner core of the adrenal glands that

also releases hormones to deal with stress

Wrapping up

- The endocrine system plays a key role in helping to coordinate and integrate complex psychological reactions.

- The nervous system and the endocrine system work together in a constant chemical conversation