Tag: mechanism of hormone action
Questions Related to mechanism of hormone action
Which among the following is the correct example of negative feedback?
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Regulation of blood calcium level
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Saliva secretion
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Secretion of pancreatic amylase
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All of the above
A- Levels of parathyroid hormone are regulated by a negative feedback loop by increasing blood calcium levels which further prevents the release of parathyroid hormone.
Which is an example of negative feedback?
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Nursing action stimulates the hypothalamus to release oxytocin that triggers mammary gland milk production.
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When the blood becomes dilute, ADH is no longer released from the hypothalamus.
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Uterine stretching sends nerve impulses to the hypothalamus that releases oxytocin that triggers uterine contraction.
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TRH stimulate the anterior pituitary to release thyroid-stimulating hormone.
When a high level of particular hormone inhibits their further secretion is called as negative feedback. As the level of water in the blood falls, negative feedback ensures that the amount of ADH rises. As the level of water in the blood rises, negative feedback ensures that the amount of ADH falls. Thus, the correct answer is option B.
Feedback control for hormone can be
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Positive only
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Negative only
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Both A and B
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None of the above
When the secretion of hormone is controlled by some factors or other hormones is called as feedback control. It can be both positive and negative. When the hormone secretion is amplified by its own secretion is called as positive feedback. When a high level of particular hormone inhibits their further secretion is called as negative feedback. Thus, the correct answer is option C.
Negative feedback occurs when
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The rate of a process increases as the concentration of product increases.
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The rate of process decreases as the concentration of product decreases.
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The rate of process decreases as the concentration of product increases.
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The rate of a process increases as the concentration of product decreases.
- A feedback mechanism for multistep reactions is a biological occurrence wherein the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
- For example, Release of estrogen from the ovaries stimulates the secretion of GnRH from Hypothalamus which in turn stimulates the secretion of LH from anterior pituitary.when the levels of LH reaches above the normal levels in the blood it stimulates the release of progesterone from corpus luteum which causes the inhibition of the release of GnRH from the hypothalamus which in turn leads to inhibition of release of LH(product) from anterior pituitary and prevents the accumulation of LH(product)in blood. Hence negative feedback.
- Hence Negative feedback occurs when The rate of process decreases as the concentration of product increases.
- So, the correct answer is 'The rate of process decreases as the concentration of product increases'.
An administration of estrogen and progesterone to the woman decreases the secretion of gonadotropins due to
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Positive feedback inhibition
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Negative feedback inhibition
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Chemical reaction between the hormones
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None of the above
- A feedback mechanism for multistep reactions is a biological occurrence wherein the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
- For example, Release of estrogen from the ovaries stimulates the secretion of GnRH from Hypothalamus which in turn stimulates the secretion of LH from anterior pituitary.when the levels of LH reaches above the normal levels in the blood it stimulates the release of progesterone from corpus luteum which causes the inhibition of the release of GnRH from the hypothalamus which in turn leads to inhibition of release of LH(product) from anterior pituitary and prevents the accumulation of LH(product)in blood. Hence negative feedback.
- Hence An administration of estrogen and progesterone to the woman decreases the secretion of gonadotropins due to Negative feedback inhibition.
- So, the correct answer is 'Negative feedback inhibition'.
Negative feedback inhibition .......... the mechanism to reverse the changes.
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Activates
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Inactivates
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Remove
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None of the above
- A feedback mechanism for multistep reactions is a biological occurrence wherein the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
- For example, Release of estrogen from the ovaries stimulates the secretion of GnRH from Hypothalamus which in turn stimulates the secretion of LH from anterior pituitary.when the levels of LH reaches above the normal levels in the blood it stimulates the release of progesterone from corpus luteum which causes the inhibition of the release of GnRH from the hypothalamus which in turn leads to inhibition of release of LH(product) from anterior pituitary and prevents the accumulation of LH(product)in blood. Hence negative feedback.
- Hence Negative feedback inhibition activates the mechanism to reverse the changes.
- So, the correct answer is 'Activates'.
The key component of hemostasis is
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Feedback mechanism
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Complexity
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Cell content
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Enzymes
Hemostasis is the process of blood coagulation or the formation of a clot to prevent blood loss when there is any injury. The main component of hemostasis is based on the positive feedback mechanism. There is activation of one coagulation factor which activates the other coagulation factor. This initiates a cascade mechanism which results in the formation of a proper clot. The mechanism stops or gets inhibited when there is formation of clot.
Which of the following prevents the accumulation of product?
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Positive feedback inhibition
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Negative feedback inhibition
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Anticoagulation
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None of the above
- A feedback mechanism for multistep reactions is a biological occurrence wherein the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
- For example, Release of estrogen from the ovaries stimulates the secretion of GnRH from Hypothalamus which in turn stimulates the secretion of LH from anterior pituitary.when the levels of LH reaches above the normal levels in the blood it stimulates the release of progesterone from corpus luteum which causes the inhibition of the release of GnRH from the hypothalamus which in turn leads to inhibition of release of LH(product) from anterior pituitary and prevents the accumulation of LH(product)in blood. Hence negative feed back.
- Hence Negative feedback inhibition prevents the accumulation of product.
- So, the correct answer is 'Negative feedback inhibition'.
Positive feedback inhibition is concerned about
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Increase in input
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Increase in output
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Bringing back output to the normal level
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None of the above
- A feedback mechanism for multistep reactions is a biological occurrence wherein the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback).
- For example, Release of estrogen(input) from the ovaries stimulates the secretion of GnRH from Hypothalamus which in turn stimulates the secretion of LH(product) from the anterior pituitary. This LH further causes the release of more estrogen(input) from the ovaries. Hence increase in input . Thus positive feedback.
- Hence Positive feedback inhibition is concerned about Increase in the input.
- So, the correct answer is 'Increase in input'.
Positive feedback occurs when
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A gene activates itself directly via negative feedback loop
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A gene activates itself indirectly via negative feedback loop
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A gene activates itself directly and indirectly via double negative feedback loop
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None of the above