1. Hypothyroidism By Megan, Mackenzie and James

2. Symptoms of Hyperthyroidism  Appetite change (decrease or increase)  Difficulty sleeping (insomnia)  Fatigue  Frequent bowel movement—perhaps diarrhea  Heart palpitations  Heat intolerance  Increased sweating  Irritability  Light menstrual periods—perhaps even missed periods  Mental disturbances  Muscle weakness  Nervousness  Problems with fertility  Shortness of breath  Sudden paralysis  Tremor/shakiness  Vision changes  Weight loss-but perhaps weight gain  Dizziness  Thinning of hair  Itching and hives  Possible increase in blood sugar

3.  The thyroid gland is the only gland affected by hypothyroidism. The thyroid curves around the anterior surface of the trachea just inferior of the thyroid cartilage that dominates the anterior surface of the larynx. Glands Affected

4.  Thyroxin(T4)  Triiodothyronine (T3)  Calcitonin: lowers blood calcium levels Target Organs/Tissues Increases metabolic rate; regulates growth and development

5.  Thyroxine (T4) :increases metabolic rate; regulates growth and development  Triiodophyronine (T3):increases metabolic rate; regulates growth and development  Calcitonin: lowers blood calcium level  Parathyroid (PTH) : raise blood calcium level Thyroid Hormones Involved

6.  Hormone imbalance is caused by:  - A Thyroid tumor.  -an overactive Thyroid gland.  -nutritional iodine insufficiency which could lead to a Thyroid goiter. This type of goiter is known as a exophthalmic goiter. Hormone Imbalance

7.  In a normal Homeostatic Thyroid loop, the hypothalamus releases hypothalamic- releasing hormone. The Anterior Pituitary then releases thyroid-stimulating hormones. The Thyroid gland releases T3 and T4 into the blood stream to increase T3 and T4 concentration, to the normal range. The Anterior pituitary gland releases the Thyroid-inhibiting hormone which causes the thyroid gland to stop releasing T3 and T4. Homeostatic Feedback Loops

8.  In an abnormal loop involving the thyroid gland there is an excess of T3 and T4 hormones. The hypothalamus releases hypothalamic-releasing hormone. The Anterior Pituitary then releases thyroid-stimulating hormones.. With inadequate iodine levels in the body the Thyroid gland releases low levels T3 and T4 into the blood stream. Because of these low levels of thyroid hormones it result in a weak negative feedback response(which does not cause the hypothalamus to send inhibiting hormones to the anterior pituitary). This causes the anterior pituitary sends excess TSH to the thyroid gland which in turn secretes more T3 and T4. Abnormal Hormone Loop

9. Hyperthyroidism Hormone Loop

10.  http://www.endocrineweb.com/conditions/hy perthyroidism/hyperthyroidism-symptoms http://www.endocrineweb.com/conditions/hy perthyroidism/hyperthyroidism-symptoms  http://www.webmd.com/a-to-z- guides/hyperthyroidism-topic-overview http://www.webmd.com/a-to-z- guides/hyperthyroidism-topic-overview  Understanding Human Anatomy and Physiology by Sylvia S. Mader Work Cited