By Table of Contents
Where Does Water Reabsorption Occur In The Nephron?
Water reabsorption in the nephron occurs in the proximal convoluted tubule. Water reabsorption in the proximal convoluted tubule of the nephron occurs by three against a concentration gradient. The sodium-potassium pump in the basolateral membrane along with the sodium-hydrogen exchanger in the apical membrane, both reabsorb sodium and water. The paracellular pathway in the tight junctions of the epithelial cell reabsorbs sodium and water. The countercurrent multiplication along with the pressure gradient in the tubule also reabsorb water and sodium..
Where does reabsorption of water occur?
In the kidneys, the blood is filtered by the nephrons in the kidneys. When the filtered blood is returned to the body, some of the water in the urine is absorbed back in to the body in a process called reabsorption. This occurs in the loop of Henle in the kidneys..
Where does reabsorption occur in the nephron quizlet?
The loop of henle is where the majority of reabsorption occurs. Before the filtrate enters the nephron’s tubule cells, about 25% of water has already been reabsorbed into the blood via the proximal convoluted tubule. The loop of henle is the area of the nephron where water reabsorption occurs, because that is where the concentration of the filtrate is the highest, which means that the concentration gradient is the steepest. If water reabsorption did not occur at all, the urine would be diluted with too much water, resulting in a very low concentration of various solutes in the urine. The concentration of solutes in the urine is what is referred to as the urine’s osmolarity..
How does reabsorption occur in the nephron?
During the reabsorption process, water enters the tubule lumen, diffuses through its epithelial cells, and passes through the luminal membrane into the hyperosmotic interstitial fluid of the renal medulla. Then, this hyperosmotic solution reenters the proximal tubule lumen, which is less hyperosmotic than the interstitial fluid of the renal medulla. Water then more readily passes into the proximal tubule lumen, thereby completing the process of reabsorption..
In which part of nephron maximum water is reabsorbed?
The maximum amount of water is reabsorbed in the proximal convoluted tubule and the descending limb of the loop of Henle..
In which part of nephron water is not reabsorbed?
Water is reabsorbed by the nephron as it passes through the three segments. The first part of the nephron is the proximal tubule. In this portion of the nephron there is no water reabsorption. The proximal tubule is responsible for filtering the blood by collecting the blood plasma and then adding a small amount of sodium to the extracted water. The second part of the nephron is the distal tubule. In this portion of the nephron, there is a small amount of water remaining in the filtrate because the remaining water is reabsorbed by the collecting ducts. The collecting ducts are responsible for completing the reabsorption of the water from the filtrate. In addition, the collecting ducts also help regulate the amount of water reabsorbed from the filtrate..
What is water reabsorption?
Water reabsorption is the process by which the kidneys expel the excess water by filtering it back into the bloodstream after passing through the kidneys. The urine is left with wastes and chemicals, and the water content is less than the amount present in the blood. This lets the blood return to a normal volume..
Where does water reabsorption occur quizlet?
The renal tubules of the kidneys are responsible for reabsorption of water. The process is also known as ultrafiltration. It is important that water reabsorption takes place because it regulates the amount of water that is excreted by the kidneys. When water reabsorption occurs, the water that is excreted is mostly salt and other minerals. The filtrate that is excreted is mostly water..
Why is water reabsorption in the descending loop and collecting duct passive?
The collecting duct is responsible for the reabsorption of water. This happens in parts of the kidney called the Loop of Henle. The Loop of Henle is a U shaped tube that runs along the descending limb of the nephron. As the water is reabsorbed, hydrogen ions are also being reabsorbed. The hydrogen ions are being secreted into the collecting duct by the cells in the collecting duct. The water in the collecting duct is reabsorbed in a passive way because it doesn’t require energy to pull the water in. It does require energy for the water to cross the membranes of the cells in the collecting duct. The hydrogen ions are secreted passively in the collecting duct because the concentration gradient is the same on either side of the membrane. There is a lower concentration of hydrogen ions on either side of the membrane, so the concentration gradient only exists when actively transporting the ions against the concentration gradient..
What is obligatory reabsorption of water in the kidney?
Obligatory water reabsorption is the process of reabsorbing the water that has passed through the nephron into the tubule. The fluid that passes through the nephron to the collecting duct would already be diluted because the loops of Henle make the renal filtrate hypotonic. The tubule can reabsorb water until the osmolarity is the same as the blood. This is achieved by active transport of sodium ions..
Can water in the bladder be reabsorbed?
No, the urine travels from the kidneys to the bladder and out of the body. The bladder is a storage organ and not an elimination organ. The urine travels from the kidneys to the bladder and into the ureters and then into the bladder. From the bladder the urine moves into the urethra and out of the body..
Which parts of the nephron are permeable to water?
The loop of Henle consists of a descending limb, a thin segment of the ascending limb, and a thick ascending limb. The thick ascending limb has permeable to water. In the proximal convoluted tubule, the luminal membrane is impermeable to water. In the distal convoluted tubule, the luminal membrane is permeable to water. In the connecting tubule, the luminal membrane is permeable to water. In the collecting duct, the luminal membrane is permeable to water. The ureter returns the urine back to the bladder. The ureter is permeable to water..
What area of the nephron is responsible for the reabsorption of most of the water from the filtrate?
The proximal convoluted tubule is responsible for reabsorption of most of the water from the filtrate. The reabsorption of water is important because if the tubules allowed the filtrate to pass through the kidney without being reabsorbed, then it would leave very little fluid in the body..
Which part of the loop of Henle is permeable to water?
The distal tubule is the part of the Loop of Henle that is permeable to water. The distal tubule is the portion of the nephron that is immedietely downstream of the Loop of Henle and immediately before the collecting duct. The primary function of the distal tubule is to take water out of the filtrate and concentrate the urine by driving all solutes, except those that are weakly- or non-ionized (such as urea and uric acid) into the renal tubule. It does this by the transporation of solutes across the basolateral (high-side) membrane into the blood. This process is known as reabsorption. The most important transporters that perform this function are members of the solute carrier family..
