By the end of this presentation, you will know: The types of hormones in the body How the endocrine and nervous systems work together The major endocrine tissues in the body, the hormones they secrete, and the functions of the hormones

The nervous and endocrine systems together make up the body’s communication network The nervous system handles things that need fast action, in fractions of a second. The endocrine system works over minutes, hours, even years. What are some processes in your body that take place over several hours’ time? Over several years’ time?

The nervous and endocrine systems work together and share some characteristics Both systems: Release chemical messengers that bind to receptor proteins on or in target cells Use some of the same chemical messengers. These compounds act as neurotransmitters in the nervous system and as hormones in the endocrine system. Contribute to feedback loops Are used by the body to communicate between cells What kind of feedback mechanisms can you think of that affect the nervous system?

The hypothalamus links the nervous system to the endocrine system The hypothalamus secretes hormones that control the production of other hormones. The hypothalamus then sends its signals to the pituitary gland. hypothalamus pituitary What role does the hypothalamus play in the brain, as part of the nervous system?

The pituitary, just below the hypothalamus, has two parts: anterior and posterior The anterior pituitary produces many hormones. Anterior pituitary hormones stimulate endocrine cells to make other hormones. What organ does MSH affect? What effect do you think it has?

The anterior pituitary produces many important hormones FUNCTION Growth hormone (GH) Targets bone, muscle, and soft-tissue cells; stimulates cells to grow and divide Melanocyte-stimulating hormone (MSH) Stimulates melanocytes to produce melanin Prolactin Induces milk production in the breasts after childbirth Adrenocorticotrophic hormone (ACTH) Stimulates the adrenal glands to produce hormones Luteinizing hormone (LH) Triggers the release of an egg from the ovary (ovulation) Thyroid-stimulating hormone (TSH) Stimulates the thyroid gland to produce hormones

HORMONES OF THE POSTERIOR PITUITARY The posterior pituitary is a vehicle for hormones produced by the hypothalamus Hormones travel along axons that extend from the hypothalamus to the posterior pituitary, where they are secreted into the bloodstream. HORMONES OF THE POSTERIOR PITUITARY HORMONE FUNCTION Antidiuretic hormone (ADH) Stimulates kidneys to retain or return water to the bloodstream Oxytocin Stimulates contraction of the uterus during childbirth If you just drank a big glass of water, what would be the response of your hypothalamus?

Your butterfly-shaped thyroid gland sits at the anterior of your throat Thyroid hormones control metabolism, the rate at which your body uses oxygen and energy. Thyroid gland

Your adrenal glands sit on top of your kidneys The adrenal glands have two parts that produce separate hormones: Adrenal cortex Medulla Adrenal gland Kidney

The adrenal cortex secretes hormones that have a variety of roles in the body FUNCTION Aldosterone Regulates ion concentrations in the bloodstream Sex steroids (estrogen, progesterone, testosterone) Affect secondary sex characteristics such as breast development and facial hair Cortisol Affects metabolism and storage of nutrients when the body is under stress What body processes do you know of in which ions are important? What stimulus to the hypothalamus do you think would start it sending signals to release aldosterone?

The adrenal medulla gives you an adrenaline rush The fight or flight hormones epinephrine (a.k.a. adrenaline) and norepinephrine act much more quickly than most hormones. What are the signs that your body is flooding with adrenaline?

Your pancreas secretes two hormones that together regulate blood sugar Insulin stimulates cells throughout your body to take up glucose. Glucagon kicks in when your blood sugar is low, and it stimulates cells to release glucose. pancreas

Gonads produce and secrete sex hormones Many of the same hormones are present in men and women, but in different amounts. The ovaries produce mostly estrogen and progesterone in regular cycles. The testes produce androgens. The main androgen is testosterone. ovaries testes