ANIMAL PHYSIOLOGY
OSMOREGULATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Less water re absorption into the blood.
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More water re absorption into the blood.
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Higher blood pressure.
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More recycling of ions into blood.
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Detailed explanation-1: -Natriuretic hormones, released primarily from the atria of the heart in response to stretching of the atrial walls, stimulate Na+ excretion and thereby decrease blood pressure.
Detailed explanation-2: -Abstract. The atrial natriuretic hormone (ANP) is a cardiac hormone which gene and receptors are widely present in the body. Its main function is to lower blood pressure and to control electrolyte homeostasis.
Detailed explanation-3: -ANP is secreted in response to: Stretching of the atrial wall, via Atrial volume receptors. Increased Sympathetic stimulation of -adrenoceptors. Increased sodium concentration (hypernatremia), though sodium concentration is not the direct stimulus for increased ANP secretion.
Detailed explanation-4: -When blood sodium levels and pressure are increased, ANP is secreted from the heart. It binds to its receptor in the kidney and blood vessels, and promotes salt excretion, lowers blood volume and relaxes the vessel.
Detailed explanation-5: -Atrial natriuretic peptide (ANP) acts acutely to reduce plasma volume by at least 3 mechanisms: increased renal excretion of salt and water, vasodilation, and increased vascular permeability.