Exercise 16-3 Time to Trace! Negative Feedback Loops arlier in this unit we poin
ID: 3505103 • Letter: E
Question
Exercise 16-3 Time to Trace! Negative Feedback Loops arlier in this unit we pointed out that each hormone has its own stimsalus for secretion. The stimulas f disturbance in the homecstasis of a particular physiologic variable such foe secretion is generally a as blood pressure, the concentration of glacose in the blood, or body emperature. The hormones response is to act on distant target cells homeostasis is restored, the activity of the glands and concentration of the hormone declines. This type of response is called a negative to cause changes that restore the variable to its normal ra nge. When feedback loop. you will be tracing a hormone's negative feedback loop from the initial homeostatic disturbance, through the hormone's effects on its target cells to restore homeontasis, and finally the decline of the concentration of the hormone in the blood. Following is an example Start: the concentration of glucose in the blood falls+ the pancreas releases glucagon glucagon in the blood rises + the hormoor glucagon causes glycogenolysis by the liver n the blood nes .+ the level of the hormone glucagon in the blood decreases , End the level of the concentration of gluco the hormone r Now its your turn! After you have completed the activity, answer Check Your Understanding question 6 (p. 444). concentration of the blood increases (ie., there is mdequate water in the blood) the hypothalamus releases the hormone the stored hormone the hormone the concentration of the blood and stores it in the is released and so its level in the blood rises the level of the hormone in the blood End 16 increases+the pancreas releases the hormone +the level of the hormone 2 Start: the concentration of glucose in the blood in the blood risesthe hormone +blood glucose levels + the level of the hormone End in the blood 3 Start: the concentration of calcium ions in the blood decreasesthe parathyroid glands release the hormone + the level of the hormone in the blood rises -+ the hormone the concentration of calcium ions in the the level of the hormone in blood the blood End Endocrine System UNIT 16 433Explanation / Answer
1. When the concentration of blood increases due to inadequate water, the hypothalamus releases the hormone ADH (antidiuretic hormone) and it is stored in the posterior pituitary and released into blood resulting in increase of its levels. The hormone ADH causes water retention and when concentration of blood decreases, the levels ADH hormone in blood decreases.
2. The concentration of glucose in blood increases, the pancreas releases the hormone insulin. The level of hormone insulin in blood increases and this causes decrease in blood glucose levels as the cells uptake the glucose. When the levels of glucose in blood decrease, the hormone insulin levels in blood decrease.
3. The concentration of calcium ions in blood decreases and the parathyroid glands release parathyroid hormone (PTH) and the levels of PTH in blood increase and result in promotion of bone resorption to increase calcium levels in blood. When the concentration of calcium ions in blood increase, the PTH levels in blood decrease.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.