Describe the regulation of water reabsorption in the kidneys.

Expert Solution

Answer :

Regulation of water reabsorption in kidney :

reabsorption is the process by which the nephron removes water and solutes from the tubular fluid (pre-urine) and returns them to the circulating blood it is called as reabsorption. both because these substances have already been absorbed once (particularly in the intestines) and because the body is reclaiming them from a postglomerular fluid stream that is well on its way to becoming urine (that is, they will soon be lost to the urine unless they are reclaimed). Substances are reabsorbed from the tubule into the peritubular capillaries. This happens as a result of sodium transport from the lumen into the blood by the Na+/K+ATPase in the basolateral membrane of the epithelial cells. Thus, the glomerular filtrate becomes more concentrated, which is one of the steps in forming urine. Reabsorption allows many useful solutes (primarily glucose and amino acids), salts and water that have passed through Bowman's capsule, to return to the circulation. These solutes are reabsorbed isotonically, in that the osmotic potential of the fluid leaving the proximal convoluted tubule is the same as that of the initial glomerular filtrate. However, glucose, amino acids, inorganic phosphate, and some other solutes are reabsorbed via secondary active transport through cotransport channels driven by the sodium gradient.

Reabsorption is a two-step process beginning with the active or passive extraction of substances from the tubule fluid into the renal interstitium (the connective tissue that surrounds the nephrons), and then the transport of these substances from the interstitium into the bloodstream. These transport processes are driven by Starling forces, diffusion, and active transport.

Sydney Mullin answered 1 year ago

How does countercurrent multiplication maintain a concentration gradient that increases water reabsorption by the kidneys?

Describe the reabsorption of filtered sodium and water in the major tubular segments.

(Q.1-5) True(a) / False(b) 1. Aldosterone increases potassium absorption. 2. ADH reduces water reabsorption. 3. Kidneys...

(Q.1-5) True(a) / False(b) 1. Aldosterone increases potassium absorption. 2. ADH reduces water reabsorption. 3. Kidneys control the blood pH. 4. Not all the glucose is absorbed back from the kidney tubules in a healthy person. 5. There are about a thousand nephrons in a human kidney.

Imagine you take a drug that increases the rate of Na reabsorption by your kidneys. All...

Imagine you take a drug that increases the rate of Na reabsorption by your kidneys. All else equal, which of the following will be true? A The volume of urine you produce per unit time will be lower after taking the drug. B The volume of urine you produce per unit time will be the same after taking the drug. C The volume of urine you produce per unit time will be higher after taking the drug.

Describe the events of filtration, reabsorption, and secretion in the kidney.

The action(s) of aldosterone is (are) to promote renal reabsorption of water. promote renal excretion of...

The action(s) of aldosterone is (are) to promote renal reabsorption of water. promote renal excretion of potassium. promote renal reabsorption of sodium. All apply.

The glomerular capillaries of nephron are associated with: pH adjustment Osmosis of water Filtration Reabsorption of...

The glomerular capillaries of nephron are associated with: pH adjustment Osmosis of water Filtration Reabsorption of nutrients Urine is stored in: Urinary bladder Urethra Ureter Bowman’s capsule The kidney secretes ___________ to increase blood pressure: Renin Angiotensinogen Angiotensin I Angiotensin converting enzyme Which enzyme converts angiotensinogen to angiotensin I Renin Angiotensinogen converting enzyme Secretin aldosterone Targets of angiotensin II are blood vessels and _________: Adrenal medulla Pituitary gland Adrenal cortex Nerves

Water reabsorption occurs between the collecting duct and the peritubular capillaries in the medulla. is influenced...

Water reabsorption occurs between the collecting duct and the peritubular capillaries in the medulla. is influenced by hormones, such as vasopressin. occurs to the greatest extent in the proximal convoluted tubule. none of these (a, b, c) are correct. all of these (a, b, c) are correct. PAH (para-amino hippuric acid) is often injected into patients to test maximum kidney function (i.e. clearance rates). That is because PAH is filtered, not reabsorbed, and secreted not filtered, not reabsorbed, but secreted...

The kidneys handle Na+ in different places of the nephron. Which statement is correct? Water is...

The kidneys handle Na+ in different places of the nephron. Which statement is correct? Water is filtered out of glomerular capillaries by bulk flow. Water is actively reabsorbed from the proximal tubule, and Na+ follows down its diffusion gradient. The permeability of the ascending limb of the loop of Henle is modified by vasopressin. Vasopressin inserts pumps in the collecting duct membrane that move water against its concentration gradient.

what is the effect of high AVP concentration on water reabsorption in PT, CCD, TAL, tAL,...

what is the effect of high AVP concentration on water reabsorption in PT, CCD, TAL, tAL, tDL?

Question