Quick Answer: What Is Counter Current Principle?

What is the countercurrent mechanism Why is it important?

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 counter current multiplier is called so?

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.

Where is countercurrent exchange found in the body?

Venous blood recovers heat from the arterial blood as the former warms on its way back to the body. Blood vessels in the neck also employ a countercurrent arrangement and that results in a brain temperature about 1°C cooler than that of the body. (A countercurrent exchange of blood oxygen occurs in the gills of fish.)

What is the meaning of counter current?

: a current flowing in a direction opposite that of another current.

What is the purpose of countercurrent flow in dialysis?

Principles of Hemodialysis Countercurrent flow maximizes the concentration gradient between blood and dialysate throughout the length of the dialyzer (see Box 22.1). When blood flow and dialysate flow are in the same direction (cocurrent), small solute clearance decreases by about 10%.

What is co current flow?

Co-current air flow, which is also referred to as parallel flow, is when the products of combustion flow in the same direction as the material. This immediately puts the coldest material in contact with the hottest gas in the kiln, resulting in a rapid initial temperature change.

What is the Pacific equatorial countercurrent?

Abstract. The Pacific equatorial countercurrent flows from west to east across the entire. Pacific, a few hundred miles north of the equator. The velocity structure of this current in the. eastern Pacific has been studied on three cruises during the period 1955-1959; in this paper the.

Do humans have countercurrent heat exchange?

Many animals (including humans) have another way to conserve heat. … Such a mechanism is called a countercurrent heat exchanger. When heat loss is no problem, most of the venous blood from the extremities returns through veins located near the surface.

Why is countercurrent flow efficient?

Counter flow heat exchangers are inherently more efficient than parallel flow heat exchangers because they create a more uniform temperature difference between the fluids, over the entire length of the fluid path. … For example, one fluid may make 2 passes, the other 4 passes.

Why is there an equatorial counter current?

The Equatorial Counter Current is an eastward flowing, wind-driven current which extends to depths of 100-150m in the Atlantic, Indian, and Pacific Oceans. … The NECC is an interesting case because while it results from wind-driven circulation, it transports water against the mean westward wind stress in the tropics.

What is meant by countercurrent flow?

This is the way that a fish’s gills absorb the maximum amount of oxygen from the water. This means that a high concentration gradient is maintained across the whole length of the gill. … This way the maximum diffusion of oxygen into the blood occurs.

Why do we reabsorb urea?

In the collecting ducts, urea is reabsorbed together with water. These mechanisms enable the formation of a high-osmolar urea gradient in the renal medulla, which is important for the renal urine concentration. … It seems like the short answer is that urea reabsorption is involved in water reabsorption from the urine.

Where does ADH have its greatest effect?

distal convoluted tubuleAnswer and Explanation: ADH has its greatest effect in the C) distal convoluted tubule. Here, this hormone acts on aquaporin molecules to remove more water from the urine, promoting resorption, thus keeping fluid levels higher in the body.

Why countercurrent flow is a more effective way of removing urea and potassium from the blood during dialysis?

The counter-current method is the most efficient because it maintains the same concentration gradient along the entire length of the circuit. The difference in efficiency (in terms of urea clearance) is approximately 20% in modern filters, when comparing concurrent and countercurrent arrangements.

Is dialysate hypotonic?

Hypotonic dialysate rapidly drops serum osmolality that leads to net fluid shift out of the vascular space, causing significant intradialytic symptoms. … Current hemodialysis (HD) practices adopt a standard dialysate sodium prescription that is typically higher than the plasma sodium concentration of most patients.

What is the advantage of counter flow system?

One other advantage for the counter flow, since the maximum temperature differences between the two flows are much smaller, they suffer less thermal forces. (Low thermal stresses will develop in counter flow as temperature difference is uniform throughout the length of the exchanger.

What is the equatorial Pacific?

The equatorial Pacific is an exception. … This reversal drives warm surface water from the western Pacific eastward, leading to the development of unusually warm sea surface temperatures east of the international dateline.

Is the equatorial current warm or cold?

List of Ocean Currents of the WorldName of CurrentNature of CurrentTsushima CurrentWarmSouth Equatorial CurrentWarmEast Australian CurrentWarmHumboldt or Peruvian CurrentCold30 more rows•Dec 3, 2020