What are the two regions of the ascending limb?
The ascending limb is structurally divisible into two regions: a thin segment, nearest the tip of the loop, and a thick segment of varying lengths, which carries the filtrate outward into the cortex and into the distal convoluted tubule.
What is the difference between thin and thick ascending limb?
The ascending limb has a thin and a thick segment. The ascending limb drains urine into the distal convoluted tubule . The thin ascending limb is found in the medulla of the kidney, and the thick ascending limb can be divided into a part that is in the renal medulla and a part that is in the renal cortex.
What is the descending limb of the body?
descending limb. 1. the proximal part of Henle's loop. 2. the descending portion of an arterial pulse tracing; called also catacrotic limb. lower limb the limb of the body extending from the gluteal region to the foot; it is specialized for weight-bearing and locomotion.
What is the ascending limb of the loop of Henle?
(Labeled at center left.) Within the nephron of the kidney, the ascending limb of the loop of Henle is a segment of the heterogenous loop of Henle downstream of the descending limb, after the sharp bend of the loop.
What is ascending limb and descending limb?
The thin descending limb turns back on itself, ascending towards the medulla, and the epithelial cells become cuboid, rich in mitochondria and have an invaginated luminal surface. The thick ascending limb extends towards the glomerulus of the same nephron and then leads into the distal convoluted tubule.
What is the descending limb?
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. Descending limb of loop of Henle. Scheme of renal tubule and its vascular supply.
What is the use of 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 ascending limb of the loop of Henle permeable to?
ionsThe loop has a sharp bend in the renal medulla going from descending to ascending thin limb. The thin ascending limb is impermeable to water, but it is permeable to ions.
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.
Where is the ascending limb of the nephron loop quizlet?
Within the nephron, the tubular fluid flows from the DESCENDING LIMB OF THE NEPHRON LOOP; ASCENDING LIMB OF THE NEPHRON LOOP directly into the PROXIMAL CONVOLUTED TUBULE; DESCENDING LIMB OF THE NEPHRON LOOP.
Why is the ascending limb 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.
Where is the thick ascending limb?
The thick ascending limb of the loop of Henle (TAL) is the first segment of the distal nephron, extending through the whole outer medulla and cortex, two regions with different composition of the peritubular environment.
What is the function of the ascending loop of Henle quizlet?
responsible for reabsorbing approximately 25% of the filtered NaCl and water and a small amount of bicarbonate. However, another major function of the loop of Henle is to enable the kidney to produce either a dilute or a concentrated urine.
What does the thick ascending limb reabsorb?
Abstract. Thick ascending limbs of Henle's loop have at least three major roles: (1) They reabsorb sodium chloride which dilutes the urine.
What substances are reabsorbed in the ascending loop of Henle?
Reabsorption in the thick ascending limb: A further 25% of the sodium and potassium is reabsorbed through the walls of the thick ascending limb of the loop of Henle via: Three-ion cotransporter (sodium/potassium/chloride) and the sodium/potassium ATPase, which as before maintains the sodium concentration gradient.
What is the function of descending loop of Henle?
The principal function of the loop of Henle is in the recovery of water and sodium chloride from urine. This function allows production of urine that is far more concentrated than blood, limiting the amount of water needed as intake for survival.
What does the thick ascending limb reabsorb?
Abstract. Thick ascending limbs of Henle's loop have at least three major roles: (1) They reabsorb sodium chloride which dilutes the urine.
What is the purpose of the loop of Henle?
This part of the nephron is called the loop of Henle. Its main function is to reabsorb water and sodium chloride from the filtrate. This conserves water for the organism, producing highly concentrated urine.
Where is the highest concentration of Na+ found?
Na+ is more concentrated outside than inside the cell.
Which is thicker, ascending or descending?
The ascending limb is much thicker than the descending limb . At the junction of the thick ascending limb and the distal convoluted tubule are a subset of 15-25 cells known as the macula densa that are part of renal autoregulation through the mechanism of tubuloglomerular feedback .
What is the ascending limb of the loop of Henle?
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 .
Which limb is impermeable to water?
Thick ascending limb. Functionally, the parts of the ascending limb in the medulla and cortex are very similar. The medullary ascending limb is largely impermeable to water. Sodium (Na + ), potassium (K +) and chloride (Cl −) ions are reabsorbed by active transport.
Is the ascending limb impermeable to water?
The thin ascending limb is impermeable to water; but is permeable to ions allowing for some sodium reabsorption. Na/K-ATPase is expressed at very low levels in this segment and thus this reabsorption is likely through passive diffusion. Salt moves out of the tubule and into the interstitium due to osmotic pressure created by the countercurrent system.
Overview
Within the nephron of the kidney, the ascending limb of the loop of Henle is a segment of the heterogenous loop of Henle downstream of the descending limb, after the sharp bend of the loop. This part of the renal tubule is divided into a thin and thick ascending limb; the thick portion is also known as the distal straight tubule, in contrast with the distal convoluted tubule downstream.
Structure
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.
The thin ascending limb is found in the medulla of the kidney, and the thick ascending limb can be divided into a part that is in the renal medulla and a part that is in the renal cortex. The ascending …
Function
The thin ascending limb is impermeable to water; but is permeable to ions allowing for some sodium reabsorption. Na/K-ATPase is expressed at very low levels in this segment and thus this reabsorption is likely through passive diffusion. Salt moves out of the tubule and into the interstitium due to osmotic pressure created by the countercurrent system.
Functionally, the parts of the ascending limb in the medulla and cortex are very similar.
Clinical significance
The thick ascending limb symporter: Na-K-Cl cotransporter.
See also
• Descending limb of loop of Henle
External links
• Nosek, Thomas M. "Section 7/7ch07/7ch07p11". Essentials of Human Physiology. Archived from the original on 2016-03-24.
• Histology image: 15804loa – Histology Learning System at Boston University
• Overview at vet.cornell.edu