The ENDOCRINE SystemThe ENDOCRINE System

What is the Endocrine System?What is the Endocrine System?

• A collection of glands that secrete HORMONES into the bloodstream

How does the endocrine system How does the endocrine system affect behavior?affect behavior?

• The endocrine system produces hormones that interact with the nervous system to control specific body organs and functions, such as metabolism, growth rate, digestion, blood pressure, sexual development, emotional response, and stress responses

• For example, adrenal glands help you cope with stress, thyroxin can make you sluggish or nervous

Endocrine system functionEndocrine system function

• Because hormones travel in the bloodstream, transmission of information is slower than the neural impulses of the nervous system

• Signals that trigger release of hormones come from the HYPOTHALAMUS

• The hypothalamus is the main link between the endocrine and nervous systems

• The hypothalamus triggers the pituitary gland, which then triggers the other glands

What are the major glands of the What are the major glands of the endocrine system?endocrine system?

• Pituitary: growth hormone, prolactin, oxytocin, endorphins

• Adrenals: epinephrine (adrenaline)

• Thyroid: thyroxin

• Pancreas: insulin

• Gonads (ovaries and testes): estrogen, progesterone; testosterone

What is HOMEOSTASIS?What is HOMEOSTASIS?

• Internal equilibrium

• Everything is in balance, hormones at the right levels