Why is there noticeable swelling in the front part of the neck of a person who vhas goiter?

The noticeable swelling in the front of the neck of a person suffering from goiter is due to the inflammation of the thyroid gland. Also, antibodies secret in autoimmune disease attack the thyroid gland and result in the formation of goiter.

Further Explanation:

The thyroid gland is present below the muscles and skin at the anterior of the neck. This gland is brownish-red in color. It consists of right and left halves mainly called lobes. These lobes resemble the wings of a butterfly. It helps in regulating the development and growth of secondary organs. The thyroid hormones released by a thyroid gland are called tri-iodothyronine (T3) and thyroxine (T4). These hormones are passed in the bloodstream and help in maintaining the body’s metabolism.

The enlarged thyroid gland is called goiter. This can develop due to inflammation of the thyroid gland or when the thyroid gland is secreting too little or too much hormone. Goiter can result from other thyroid-related issues, like thyroid cancer, thyroid cyst or thyroid infection. Also, individuals who don't include an adequate level of iodine in their diet results in the formation of goiter.

Goiter can also result from autoimmune diseases. Graves' disease and Hashimoto's disease are autoimmune diseases. In these diseases, the body secretes proteins that are mainly called antibodies. These antibodies attack the thyroid gland and result in the formation of goiter.

Learn More:

Answer Details:

Grade: Senior School

Subject: Biology

Chapter: Endocrine imbalance and diseases

Keywords:

Thyroid gland, goiter, grave’s’ disease, hashmito’s disease, thyroid cancer, swelling, antibodies, protein, hormone, thyroxine (T4) and tri-iodothyronine (T3).

d. i assume the underlined word is "role." reformat if it isn't.

explanation:

role is closest to part because when replacing words, "playing a vital decision," "playing a vital activity," and "playing a vital dollar" don't make logical sense. the only meaningful choice is "playing a vital part."

this fits one of merriam-webster's definitions of role: "a function or part performed especially in a particular operation or process."