Question

When the levels of thyroid hormones in the blood are low, which of the following series of events follows?

The hypothalamus secretes thyrotropin-releasing hormone (TRH), the anterior pituitary stops secreting thyroid-stimulating hormone (TSH), and the thryroid stops secreting thyroid hormones.


The hypothalamus secretes thyroid-stimulating hormone (TSH), the anterior pituitary also secretes TSH, and the thyroid secretes thyroid hormones.


The hypothalamus secretes thyroid-stimulating hormone (TSH), the anterior pituitary stops secreting TSH, and the thyroid stops secreting thyroid hormones.


The hypothalamus secretes thyrotropin- releasing hormone (TRH), the anterior pituitary secretes thyroid-stimulating hormone (TSH), and the thyroid secretes thyroid hormones.

Answer 1

The hypothalamus secretes thyrotropin- releasing hormone (TRH), the anterior pituitary secretes thyroid-stimulating hormone (TSH), and the thyroid secretes thyroid hormones.

Step-by-step explanation:

The metabolism controlling hormone is Thyroid. It absorbs iodine and makes use of it. The thyroid regulating glands are hypothalamus and pituitary. The low and high thyroid levels cause different conditions in human body. A lower level causes hypothyroidism.

In this condition, the TSH secreting hormone TRH makes the secretion of Thyroid stimulating hormone- TSH by the pituitary. These event chain influences thyroid to produce hormones at large amount.

Answer 2

The correct answer is : The hypothalamus secretes thyrotropin- releasing hormone (TRH), the anterior pituitary secretes thyroid-stimulating hormone (TSH), and the thyroid secretes thyroid hormones.

Step-by-step explanation:

The decrease in thyroid hormones (T3 and T4) is known as hypothyroidism, which is treated with sodium levothyroxine. In this case, low hormone levels have a negative feedback effect on the hypothalamus. This increases the release of HRT and it stimulates the release of TSH from the adenohypophysis. The latter stimulates the follicles of the thyroid gland, generating greater production of thyroid hormones.