1. Endocrinology For each hormone, state the following: - name and location of secreting organ - chemical class and receptor type (where given) - target(s) and main effect on target(s) = function - control pathway Compare and contrast peptide, steroid and amine hormones.

3. Classes of hormones: 1. Peptide - chain of amino acids, protein 2. Steroid - derived from cholesterol 3. Amine - derived from an amino acid * Different mechanisms of action for peptide hormones working through membrane receptors and steroids, vitamin D and thyroid hormones working through nuclear receptors. * Different hormone actions exerted through changes in protein phosphorylation or through changes in gene expression.

6. Major functional areas under endocrine control Digestion and glucose metabolism Osmoregulation (principally regulation of water and NaCl balance) Calcium balance Growth Reproduction Immune function

7. Endocrine homeostatic control of [Ca ++ ] plasma Parathyroid Hormone (PTH) Increases [Ca ++ ] plasma Most important in control of [Ca ++ ] plasma Calcitonin Reduces [Ca ++ ] plasma * warning - gross anatomy picture is next

8. Thyroid - Normal thyroid gland, anterior to trachea. Structure: a right lobe and a left lobe connected by a narrow isthmus. Normal weight: 10 to 30 grams. It cannot easily be palpated.

9. Parathyroids Four (usually) found on dorsal surface of thyroid glands. (These are hyperplasic) Secrete PTH

10. Parathyroid Hormone Maintains homeostatic plasma [ Ca 2+ ] PTH stimulates…1) osteoclasts to resorb bone 2) kidneys to reabsorb Ca 2+ 3) intestines to increase Ca 2+ absorption

11.  [ Ca 2+ ] plasma causes PTH  or  ?  PTH causes [ Ca 2+ ] plasma  or  Represent these on a graph.

12. Calcitonin has effects opposite of PTH effects on bones, kidneys.