Unit 9: The Endocrine System

Endocrine System Produces hormones from the glands. But, wait … not all glands are in the endocrine system. Only ductless glands. Secrete chemicals called hormones. Sent directly into bloodstream

Anatomy Hormones = The main regulators of metabolism, growth and development, reproduction and other important body functions. Endocrine glands, hormones and their functions – Table 10-1 in text.

Seminar Topic: Endocrine and nervous systems Different systems yet similar functions COMMUNICATION CONTROL

Nervous System, Review Communication – through nerves, spinal cord and brain Control – Sending/receiving stimuli from the different areas of the body Result – rapid, brief control through fast-acting nerve impulses

Endocrine System Communication – Secreted directly into bloodstream Control – Hormones promote/inhibit chemical responses Result – slower, prolonged control through hormones

Pituitary Gland “master gland” Connected to the hypothalamus (brain) by stalk Size of cherry Adenohypophysis – anterior Neurohypophysis - posterior

Anterior Pituitary (A.P.) Communication – hypothalamus  A.P.  other endocrine glands ControlResult TSH thyroid hormones ACTHadrenal cortex GHcell growth FSH/LHovaries/ testes Prolactinmilk secretion

Posterior Pituitary (P.P.) Communication – hypothalamus  P.P.  other organs Only releases hormones produced by hypothalamus ControlResult ADH kidney oxytocinuterus/ mammary

Anterior gland Posterior gland ADH Oxytocin FSH LH Prolactin TSH

Endocrine & Nervous The combined nervous and endocrine functions of the hypothalamus and pituitary gland allow for strong influence on homeostasis. What are some areas of homeostasis affected by just these two parts?

Thyroid Gland Communication – A.P.  thyroid  other organs ControlResult T3 & T4 all cells calcitoninbone

Thyroid Gland, con’t Side note --- triiodothyronine What do you notice about this compound?

Parathyroid Gland Communication – parathyroid  bone/blood Control – parathormone Result – increases blood levels of calcium

Adrenal (suprarenal) Glands - Cortex Communication – A.P.  adrenal cortex  blood (kidney); glucose; ovaries ControlResult aldosterone kidney cortisolglucose sex hormones ovaries

Adrenal (suprarenal) Glands - Medulla Communication – autonomic nervous system  fight – or - flight ControlResult epinephrine (adrenaline) body - stress norepinephrinebody – status quo

Pancreas Communication – blood glucose  islets of Langerhans  blood and liver ControlResult glucagonincrease blood glucose insulindecrease blood glucose

Reproductive Organs Communication – A.P.  ovaries/testes  female\ male sex organs Control – estrogens; progesterone; testosterone Result – sexual characteristics; reproduction

Thymus Communication – thymus  immune system Control – thymosin Result – lymphocytes

Pineal Gland Communication – optic nerve  pineal gland  ovaries; limbic system Control – melatonin Result – puberty in females; circadian rhythm; sleep

Questions???