Goiters may occur due to iodine insufficiency, but other causes are possible. Which of the following would NOT tend to result in
increased size of the thyroid gland? A. High levels of thyrotropin releasing hormone.
B. High levels of thyroid stimulating hormone.
C. High levels of thyroxin and triiodothyronine.
D. All of the above would tend to increase the size of the thyroid gland.
E. None of the above would tend to increase the size of the thyroid gland.
Thyroid is primarily caused by lack of iodine but there are other reasons as well that lead to increased size of the thyroid gland. Some of these reason is
a) over- or underproduction of thyroid hormones
b) Nodules in the glans
Some times, due to overstimulation immune system itself attack the thyroid gland thereby producing excess thyroxine and hence causing the thyroid to swell
The plant cell has a cell wall, chloroplasts, plastids, and a central vacuole—structures not found in animal cells. Plant cells do not have lysosomes or centrosomes.