Thyroid and Thymus Gland

By: Morgan Bohl, Jennifer Ballard, Ardra Anil

5th period

January 13, 2015

Thyroid Gland

Location and appearance

It is located on the anterior side of the neck, below the skin and muscular layers. It has a butterfly-shape and wraps around the trachea.

What hormones and types of hormones does it produce? Effect? How does it affect homeostasis?

Thyroxine (T4), triiodothyronine (T3), and calcitonin. Thyroxine regulates the body’s metabolism. Triiodothyronine also helps regulate everyday bodily functions, such as heart and digestive maintenance, along with other functions. Calcitonin regulates the levels of calcium and phosphate in the bloodstream. Thyroxine and triiodothyronine both help to maintain homeostasis by regulating different functions in the body, while calcitonin focuses on regulating the levels of calcium and phosphate in the blood.

Feedback mechanisms? Antagonistic hormones?

The main feedback system that controls the release of the thyroid hormones is a negative feedback loop. The body detects when the concentration of the hormones released by the thyroid is too high or too low, signals are sent to the thyroid to stop producing or start producing the hormones to maintain homeostasis.

Disease or disorders?

Goiter- enlarging of the thyroid

Hyperthyroidism- thyroid releases too much thyroid hormones

Hypothyroidism- thyroid releases too little thyroid hormones

Graves disease- causes a large variety of symptoms caused by overproduction of thyroid hormones

Thyroid nodules- mostly not harmful, small fluid filled or solid lumps within the thyroid.

How are these conditions treated?

Goiter- If the goiter is caused by hypothyroidism, it may be treated with medication. Some goiters caused by a lack of iodine may be treated by radioactive iodine. Surgery is also an option.

Hypothyroidism and Hyperthyroidism- prescribed medication to balance out thyroid hormone levels

Graves’ Disease-radioactive iodine therapy, anti-thyroid medication, beta blockers, or surgery to remove the thyroid.

Thyroid Nodules- Most modules are benign, which would be treated with surgery or thyroid hormone suppression therapy (which is unclear if it truly works). Cancerous nodules would be treated with surgery.

Thyroid work sited

http://www.endocrineweb.com/conditions/thyroid/your-thyroid-gland

http://www.endocrineweb.com/conditions/thyroid/your-thyroid-gland

http://www.yourhormones.info/hormones/triiodothyronine.aspx

http://www.endocrineweb.com/conditions/thyroid/how-your-thyroid-works

http://www.vivo.colostate.edu/hbooks/pathphys/endocrine/basics/control.html

http://www.hormone.org/diseases-and-conditions/thyroid/overview

Thymus

Location and appearance

The thymus gland is a flask-shaped organ lying in the lower neck and upper part of the mediastinum (superior mediastinum) in the chest cavity.

What hormones and types of hormones does it produce? Effect? How does it affect homeostasis?

Thymosin is the hormone released by the thymus. It stimulates the development of T cells.

The produced T cells migrate to the lymphoids aiding the immune system fighting diseases

Feedback mechanisms?

Release hormones and release inhibiting hormones

This gland secretes hormones that are commonly referred to as humoral factors and are important during puberty. The role of these hormones is to make sure a person develops a healthy immune system.

The gland releases a hormone that stimulates the production of a certain type of white blood cell in the bone marrow; these cells, called thymocytes are transported by the bloodstream to the thymus. There, the organ "programs" the cells to attack antigens that invade the body and to not attack normal cells in the body itself. Once developed, these T lymphocytes, or T cells, circulate through the bloodstream and collect in the lymph organs the spleen and lymph nodes for future use.

What happens if the gland doesn’t work properly?

If the thymus is removed in infancy or develops improperly, the immune system may be compromised. Much of the body's immune system development happens before birth, so removing the organ even in a young child won't necessarily cause extreme damage to the child's immunity. When the thymus doesn't develop correctly, however, it can cause immune deficiency, making the person much more susceptible to infections.

Disease or disorders?

Cancer is rare in this part of the body, but tumors can develop in the thymus. Called a thymoma, these tumors most often occur in people with other medical conditions including myasthenia gravis and some autoimmune diseases. Symptoms include coughing, wheezing, and chest pain, and treatment can include surgery to remove the tumor along with radiation or hormone therapy. The prognosis for thymoma depends mostly on how far the cancer has progressed

The thymus is thought to play a role in the development of myasthenia gravis, a condition in which the T cells attack the nerves where they connect to the muscles. The removal of the organ, called a thymectomy, is often performed to relieve the symptoms related to this condition.

How are these conditions treated?

Research is being conducted to determine whether or not regenerating the thymus gland or preventing its deterioration could improve immunity in older people. Scientists question whether the organ could play a role in fighting cancer and HIV/AIDS, which directly attacks T cells. Numerous autoimmune diseases such as multiple sclerosis, lupus, and diabetes might also be managed more effectively through better understanding the gland's function.

Thymus work Sited

http://www.healthhype.com/thymus-gland-function-location-anatomy-and-parts.html

http://www.hormone.org/hormones-and-health/the-endocrine-system/endocrine-glands-and-types-of-hormones#Thymus

http://www.wisegeek.org/what-is-the-thymus-gland.htm