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Introduction:
There are clusters of specialized cells present in the hypothalamus which are known as neurosecretory cells. Thin fibers or axons are grown by neurosecretory cells which end in capillary bed and connect hypothalamus to anterior lobe of the pituitary. The neurosecretory cells produce six different regulatory hormones which can be either releasing or inhibiting hormones.
Answer to Problem 1MC
Correct answer:
The neurosecretory cells in the hypothalamus produce hormones which are involved in the reabsorption of water by the kidney. Therefore, option (c) is correct.
Option (c) is given as “produce hormones that regulate water reabsorption in the kidney”.
Explanation of Solution
Justify reasons for the correct statement:
The neurosecretory cells of the hypothalamus are involved in the synthesis of peptide hormones, their storage, and release. The neurosecretory cells produce antidiuretic hormone and oxytocin hormone. The antidiuretic hormone maintains blood pressure, tissue water, and volume of blood by regulating the amount of water and thereby controlling the concentration of urine.
Hence, option (c) is correct.
Justify reasons for the incorrect statements:
Option (a) is given as “release growth hormone and prolactin”.
The growth hormone and prolactin are released by the anterior lobe of the pituitary. Prolactin stimulates the development of mammary glands and growth hormone stimulates the growth of bone and increases synthesis of proteins. These hormones are not released by neurosecretory cells. Hence, it is a wrong answer.
Option (b) is given as “release hormones that control hormone secretion by cells in the posterior pituitary”.
The neurosecretory cells in the hypothalamus release six different regulatory hormones. All these hormones regulate the release of hormones from the anterior lobe of the pituitary. The hormones released by neurosecretory cells do not regulate hormonal secretion of posterior pituitary. Hence, it is a wrong answer.
Option (d) is given as “produce hormones that stimulate glucose uptake by muscle cells”.
The hormone which stimulates the uptake of glucose by muscle cells is insulin. Insulin is produced by beta cells of the pancreas and not neurosecretory cells in the hypothalamus. Hence, it is a wrong answer.
Hence, options (a), (b), and (d) are incorrect.
The neurosecretory cells in hypothalamus form axons which end in the capillary bed in the stalk which connects hypothalamus to anterior lobe of the pituitary. These cells secrete six different regulatory hormones which regulate the hormonal secretion of the anterior pituitary. Apart from these six hormones, neurosecretory cells also release oxytocin and antidiuretic hormone. The antidiuretic hormone regulates the reabsorption of water by the kidney.
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Chapter 38 Solutions
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