The primary function of the loops of Henle and the thick ascending limb of the distal tubule is the concentration of urine utilizing a principle called ‘countercurrent multiplication. ‘ The medulla possesses a gradient of urea and salt with increasing concentrations of these solutes closer to the papillae.
What is the function of the ascending loop of Henle quizlet?
The thick ascending limb of nephron loop connects with the distal convoluted tubule, which connects with the urine connecting duct. The loop of henle dips down into the medulla, which is highly salty because of the ion absorption, Sodium is constantly being pumped out of the ascending limb into the medulla.
What is the purpose of the ascending limb?
The thick ascending limb occupies a central anatomic and functional position in human renal physiology, with critical roles in the defense of the extracellular fluid volume, the urinary concentrating mechanism, calcium and magnesium homeostasis, bicarbonate and ammonium homeostasis, and urinary protein composition.
What is the function of descending loop of Henle?
The descending portion of the loop of Henle is extremely permeable to water and is less permeable to ions, therefore water is easily reabsorbed here and solutes are not readily reabsorbed.
What is the difference between ascending and descending loop of Henle?
The key difference between ascending and descending loop of Henle is that ascending loop of Henle is the thicker segment of the loop of Henle located just after the sharp bend of the loop while descending loop of Henle is the thinner segment located just before the sharp bend of the loop.
What is the ascending loop of Henle permeable to?
The cells here are permeable to water and thus the salt and urea concentration rises within the fluid by the time it reaches the bend. The ascending limb is permeable to sodium chloride, which passes out of the tubule into the medullary tissue surrounding it.
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Why is the ascending loop of Henle impermeable to water?
The thin ascending limb is impermeable to water, due to it having no aquaporin channels. However, Na+ reabsorption still occurs passively through epithelial Na+ (eNaC) channels. Chloride (Cl–) ions are also reabsorbed in the thin ascending limb through Cl– channels.
Why is the descending loop of Henle thinner than the ascending loop of Henle?
The thin descending loop is highly permeable to water (which is easily transferred to the interstitium) and less permeable to solutes. On the other hand, the thin ascending limb is highly permeable to sodium but impermeable to water.
What substance is reabsorbed in the ascending limb of the loop of Henle quizlet?
Na+ is actively being pumped out of thick ascending limb of LOH to be reabsorbed. This gradient is used by the collecting ducts under the influcence of ADH to control the amount of water that is excreted or reabsorbed.
Is the ascending limb permeable to water?
The thick ascending limb actively reabsorbs NaCl but has an extremely low transepithelial osmotic water permeability, even in the presence of vasopressin (6).
Where is the descending loop of Henle?
Within the nephron of the kidney, the descending limb of loop of Henle is the portion of the renal tubule constituting the first part of the loop of Henle.
Why are the two parts of the nephron loop called descending and ascending?
Why are the two parts of the nephron loop called descending and ascending? (a) The descending loop is the portion that carries filtrate deep into the renal medulla, away from the cortex. The ascending loop carries filtrate back toward the kidney surface. … The ascending loop carries filtrate back toward the cortex.
What is the ascending loop?
The ascending limb of the loop of Henle is a direct continuation from the descending limb of loop of Henle, and one of the structures in the nephron of the kidney. The ascending limb has a thin and a thick segment. The ascending limb drains urine into the distal convoluted tubule.
What happens as the filtrate progresses up the ascending limb of the loop of Henle?
As the filtrate enters the ascending limb of the loop of Henle, the tube becomes impermeable to water and ions are pumped into the interstitium. This creates a gradient of higher ion concentration in the medulla and dilutes the filtrate.
Why is the ascending limb hypotonic?
The ascending limb transports Na+ and some urea into surrounding medullary tissue. It is impermeable to water. So it makes urine dilute or hypotonic.
What is the importance of having a long loop of Henle and short loop of Henle in a nephron?
The longer the Loop of Henle, the higher the osmolarity of the fluid as it contains more water. The short loops of the cortical nephrons passively reabsorb urea in the thick ascending limbs.
What is the function of the proximal convoluted tubule?
The function of the proximal tubule is essentially reabsorption of filtrate in accordance with the needs of homeostasis (equilibrium), whereas the distal part of the nephron and collecting duct are mainly concerned with the detailed regulation of water, electrolyte, and hydrogen-ion balance.
Why is ascending loop of Henle thicker?
Thick ascending limbs of Henle’s loop have at least three major roles: (1) They reabsorb sodium chloride which dilutes the urine. … (3) They reabsorb large amounts of potassium, calcium, and magnesium in an energy-efficient manner.
Where do reabsorbed substances go quizlet?
– During reabsorption, molecules first must leave the tubule lumen, then cross into the interstitial space. From there, reabsorbed substances move into the peritubular capillaries (or vasa recta).
Which of the following is important to establishing the concentration gradient observed in interstitial fluid of the renal medulla?
Which of the following is important to establishing the concentration gradient observed in interstitial fluid of the renal medulla? The ascending thick limb of the loop of Henle contains salt pumps and is impermeable to water. The descending limb is permeable to water.
What stimulates the release of antidiuretic hormone quizlet?
An increase in blood osmolarity, causes ADH to be released into the body so that the kidneys can reabsorb water, decreasing the osmolarity of the blood.
What is unique about transport epithelial cells in the ascending loop of Henle?
Whatis unique about transport epithelial cells in the ascending loop of Henle in human kidneys? They are not in contact wilh interstitial fluid Their merbranes are impermeable to water abo 50% of their cell mass comprised of smooth endoplasmic reticulum They are not affected by high !
Which part in the loop of Henle absorbs maximum water?
So, the correct answer is ‘Proximal convoluted tubule‘.
Why the filtrate becomes more dilute as glomerular filtrate moves through the ascending loop of Henle?
As glomerular filtrate moves through the ascending loop of Henle, the filtrate becomes for dilute. Why? The ascending loop of Henle is permeable to ions but impermeable to water. … It can become more dilute by either increasing its concentration of water or decreasing its concentrations of small molecules.