3. The Endocrine System VS 223 Dr. Noland

4. Endocrine Glands Secrete their product directly into bloodstream Known as “ductless” glands

6. Hormones Act on target organs due to specific receptors located on the target plasma membrane

7. Neuroendocrine Reflex Nerve input on the afferent end Hormonal input on the efferent end Suckling reflex Induced ovulation in cats, rabbits

8. Endocrine Glands Discrete gland - Adrenal gland Organ – Duodenum Combo of Exocrine/Endocrine - Pancreas

9. Classification of Hormones Peptides – chains of amino acids –Most hormones Amines – tyrosine derivatives –Catecholamines, T4 Steroids – cholesterol derivatives –Gonadal hormones and adrenal cortical hormones

10. Mechanisms of Action Hormones circulate in the bloodstream and bind with target organ cell receptors to affect a change in the target cell

11. Hydrophilic Hormones Peptides and Catecholamines

12. Lipophilic Hormones Steroids and Thyroid

13. Hormonal Action

14. Feedback Regulation