1. Biology 3201 13.2 Endocrine glands (Thyroid & parathyroid glands)

2. Thyroid is butterfly shaped and is wrapped around the larynx.

3. Parathyroid glands are 4 clumps of cells imbedded in the thyroid.

5. When thyroxine levels are high hypothalamus does NOT produce TRH which causes thyroxine levels to drop.
When thyroxin levels are low the hypothalmus produces TRH which causes thyroxin levels to rise and the cycle continues

6. Hyperthyroidism: cause Antibodies attach to TSH receptors on thyroid
Thyroid is constantly producing Thyroxin

7. Hyperthyroidism: symptoms Increased metabolic rate
Eat lots & lose weight
Enlarged thyroid
Muscle weakness
Sweating & warm skin
Bulged eyes

8. Hyperthyroidism: treatments Remove thyroid Thyroid blocking drugs
Radioactive iodine causes death of overactive thyroid

10. Hypothyroidism Opposite of Hyperthyroidism
Caused by a lack of iodine in diet and consequently lack of thyroxine production.

11. Hypothyroidism Symptoms Low metabolic activity
Reduced tolerance to cold
Decreased heart rate
Weight gain but poor appetite.
Decreased mental capacity
Poor physical development

12. Parathyroid & Thyroid

13. Thyroid produces calcitonin
Reduces Blood Ca levels
Calcitonin increases rate of Ca deposits in bone
increases Ca in urine
Parathyroid produces PTH
Increases Blood Ca levels
PTH takes calcium from bone and puts in blood.
Kidneys reabsorb more Ca
Intestines absorb more Ca

14. Good Web Sites on Thyroid