1. The Thyroid Gland
Celina Brown

2. The Thyroid Gland One of the largest endocrine glands
The thyroid gland is located low in the front of the neck
The gland is shaped like a butterfly and wraps around the windpipe or trachea.
Controls how quickly the body uses energy, makes proteins, and controls the body’s sensitivity to hormones

3. Thyroxine Tyrosine-based hormones produced by the thyroid gland
Iodine is necessary for production
Effects of thyroxine in the body:
Increases cardiac output
Increases heart rate
Increases ventilation rate
Increases basal metabolic rate
Potentiates brain development
Thickens endometrium in females
Increase metabolism of proteins and carbohydrates 

4. Thyroxine Regulation

5. Iodine Deficiencies Thyroxine is heavily composed of iodine
If there is not enough iodine in the body, there will be a resulting decrease in thyroxine
The body does not make iodine, so it’s an essential part of your diet.
Iodine deficiency can lead to hypothyroidism, mental disorders in infants whose mothers were iodine deficient, and goiters

6. Goiters
A goiter is the swelling of the neck resulting from enlargement of the thyroid gland
The thyroid swells when it is not functioning properly
This is mostly due to an iodine deficiency Hyperplasia of thyroid to compensate for decreased efficiency

7. 3 Classes of Goiters
Class One Goiter cannot be seen, but it can be felt.
Class Two Goiter is both easily felt and seen.
Class Three
Goiter is very large and causes pain. Pressure in the neck can result in compression marks.

8. Hypothyroidism
Hypothyroidism is a condition characterized by abnormally low thyroid hormone production.
This is, once again, associated with an iodine deficiency, or simply a malfunctioning thyroid gland (most commonly Hashimoto’s Disease)
Since the thyroid gland is responsible for producing hormones that influence growth, development, and many cellular and metabolic processes, insufficient thyroid hormone has many consequences on the body

9. Hypothyroidism Symptoms Delay in growth (in children and teens)
Poor memory and concentration
Fatigue
Muscle weakness
Feeling cold
Increased blood cholesterol
Shortness of breath
Depression
Weight gain with poor appetite
Slowed heart rate
Treatments
Hormone Replacement: Standard treatment for hypothyroidism involves daily use of the synthetic thyroid hormone levothyroxine (Levothroid, Synthroid, others). This oral medication restores adequate hormone levels, reversing the signs and symptoms of hypothyroidism.

10. Hyperthyroidism
Often referred to as an overactive thyroid, is a condition in which the thyroid gland produces and secretes excessive amounts of thyroid hormones
Can be cause by: Graves' disease Toxic thyroid adenoma Toxic multinodular goiter

11. Hyperthyroidism Symptoms Increased appetite Tremors
Increased heart rate
Nervousness
Sudden weight loss
Sweating
Increased sensitivity to heat
Enlarged thyroid gland
Digestive fluctuations
Difficulty sleeping
Treatments
Radioactive Iodine
Taken orally, it shrinks the thyroid, reducing it’s hormone producing activity.
Anti-thyroid medications.
Drugs that prevent the thyroid from producing excess amounts of hormones
Beta blockers.
Won’t reduce thyroid levels, but will reduce raped heart rate and prevent palpitations.
Surgery (thyroidectomy).
A rare treatment for those who can’t tolerate drugs or radioactive iodine therapy.

12. Question Time!
1) Is the thyroid an endocrine of exocrine gland? How do you know?
2) Is the thyroid gland an example of a negative or positive feedback system? How do you know?
3) Describe the shape and location of the thyroid.
4) Describe the difference between hypothyroidism and hyperthyroidism.
5) List three symptoms of hypothyroidism.
6) List two methods of treating hyperthyroidism.
7) Name one way hypothyroidism might be prevented.