The term derives from the form and function of the loop of Henle, which consists of two parallel limbs of renal tubules running in opposite directions, separated by the innterstitial space of the renal medulla.

Why loop of Henle is called countercurrent multiplier?

The structure of the loop of Henle and associated peritubular capillary create a countercurrent multiplier system (Figure 25.6. 1). The countercurrent term comes from the fact that the descending and ascending loops are next to each other and their fluid flows in opposite directions (countercurrent).

Why is it called counter current?

Because the blood flow through these capillaries is very slow, any solutes that are reabsorbed into the bloodstream have time to diffuse back into the interstitial fluid, which maintains the solute concentration gradient in the medulla. This passive process is known as countercurrent exchange.

What does countercurrent multiplier system mean?

countercurrent multiplier system An active process occurring in the loops of Henle in the kidney, which is responsible for the production of concentrated urine in the collecting ducts of the nephrons.

What is the difference between countercurrent exchange and countercurrent multiplier?

Countercurrent multiplication is something the tubule does to create the high interstitial osmolality, and a large osmolality gradient between the renal medulla and the renal cortex. The countercurrent exchange mechanism is something the vasa recta do to maintain this gradient.

What is a countercurrent multiplier in nephron?

Countercurrent multiplication was originally studied as a mechanism whereby urine is concentrated in the nephron. Initially studied in the 1950s by Gottschalk and Mylle following Werner Kuhn’s postulations, this mechanism gained popularity only after a series of complicated micropuncture experiments.

What is the function of countercurrent multiplier?

The counter-current multiplier or the countercurrent mechanism is used to concentrate urine in the kidneys by the nephrons of the human excretory system. The nephrons involved in the formation of concentrated urine extend all the way from the cortex of the kidney to the medulla and are accompanied by vasa recta.

Why are the kidneys referred to as Osmoregulatory structures?

Kidneys regulate the osmotic pressure of a mammal’s blood through extensive filtration and purification in a process known as osmoregulation. All the blood in the human body is filtered many times a day by the kidneys. Kidneys eliminate wastes from the body; urine is the filtrate that exits the kidneys.

What is the purpose of the countercurrent mechanism?

FUNCTION: To create urine with an osmolality different from serum osmolality. -To conserve water, the countercurrent mechanism generates urine with osmolality greater than plasma. This concentrated urine is produced when ADH is present in the plasma (normal physiological condition).

What is significance of counter current mechanism?

Similarly, the countercurrent mechanism also plays a significant role in the formation of concentrated urine. The mechanism uses the nephrons available in the kidneys to form concentrated urine. These nephrons act as careers in the formation of concentrated urine from the cortex to the medulla.

What is the countercurrent multiplier and why is it important?

The loop of Henle utilizes the countercurrent multiplier system to increase the concentration of solute and ions within the interstitium of the medulla. This ultimately allows the nephron to reabsorb more water and concentrate the urine while at the same time using as little energy as possible.

What is the countercurrent multiplier system quizlet?

Countercurrent Multiplier System: Water is reabsorbed at the level of the descending loop primarily due to the active pumping of –+ (and the passive diffusion of Cl-) that happens in the —- tubule.

What is the purpose of the countercurrent multiplier quizlet?

FUNCTION: To create urine with an osmolality different from serum osmolality. -To conserve water, the countercurrent mechanism generates urine with osmolality greater than plasma.

What is a countercurrent exchange system?

Countercurrent exchange is a mechanism occurring in nature and mimicked in industry and engineering, in which there is a crossover of some property, usually heat or some chemical, between two flowing bodies flowing in opposite directions to each other.

What is countercurrent exchange in fish?

Fish gills use a design called ‘countercurrent oxygen exchange’ to maximize the amount of oxygen that their blood can pick up. Countercurrent oxygen exchange (shown in the figure above) means the blood flows through the gills in the opposite direction as the water flowing over the gills.

What is the countercurrent exchanger in the kidney?

It is generally accepted that the microcirculation of the renal medulla functions as a countercurrent exchanger that traps NaCl and urea deposited to the interstitium by the loops of Henle and collecting ducts, respectively.