Hormone that decrease calcium lavel in blood :-a)Thyroxineb)Parathormonec)Thyrocalcitonind)CortisolCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

The hormone calcitonin, which is produced by the parafollicular (or C) cells of the thyroid, has the opposite effect on blood calcium levels as PTH. Calcitonin decreases blood calcium levels by inhibiting osteoclasts, stimulating osteoblasts, and stimulating calcium excretion by the kidneys. Hence, Option C.

Answer

Calcitonin secreted by thyroid glands decreases calcium level in the blood and parathormone secreted by parathyroid gland increases blood calcium level.

Answer

Thyrocalcitonin
Thyrocalcitonin, also known as calcitonin, is a hormone that plays a crucial role in regulating calcium levels in the blood. It is produced by the thyroid gland in response to high levels of calcium in the blood.

Function: Thyrocalcitonin works by reducing the amount of calcium in the blood. It does this by inhibiting the activity of osteoclasts, which are cells responsible for breaking down bone tissue and releasing calcium into the bloodstream. By decreasing the activity of osteoclasts, thyrocalcitonin helps to lower blood calcium levels.
Effects: The main effect of thyrocalcitonin is to promote bone formation and reduce bone resorption. This leads to a decrease in the amount of calcium released from bones into the bloodstream. Additionally, thyrocalcitonin also enhances the excretion of calcium by the kidneys, further helping to lower blood calcium levels.
Regulation: The secretion of thyrocalcitonin is primarily regulated by the level of calcium in the blood. When blood calcium levels are high, the thyroid gland releases thyrocalcitonin to reduce calcium levels. Conversely, when blood calcium levels are low, the parathyroid hormone is released to increase calcium levels.
Disorders: In conditions such as hypercalcemia (high blood calcium levels), thyrocalcitonin may be used therapeutically to help lower calcium levels. On the other hand, hypocalcemia (low blood calcium levels) may result from decreased production of thyrocalcitonin or increased activity of osteoclasts.

In conclusion, thyrocalcitonin is a hormone that plays a vital role in regulating calcium levels in the blood by promoting bone formation, reducing bone resorption, and enhancing calcium excretion. Its actions help to maintain the delicate balance of calcium in the body and prevent complications related to abnormal blood calcium levels.

Answer

Calcitonin secreted by parafollicular cells of thyroid gland is hypocalcemic hormone. It promote mineralization i.e deposition of excess calcium from blood to bones.
hypo secretion of calcitonin: osteoporosis
hypersecretion:osteitis

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