Explain why countercurrent flow met the goals and why parallel flow did not meet the goals.

In fluid or a flowing body when there is interexchange or a crossover of some fluids with each other is called countercurrent flow while when the fluid flows in the same direction then it is called parallel flow.

Countercurrent meets goals because of concentration gradient differences.

Therefore, countercurrent achieves its goal while parallel dies not.

Learn more about countercurrent and parallel flow here:

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Countercurrent flow met the goals due to difference in concentration gradient.

Explanation:

Countercurrent flow met the goals because it flows in opposite direction while on the other hand, parallel flow did not meet the goals because it flows in the same direction. For example. the blood flows in one direction and the dialysate flows in the opposite direction. The countercurrent flow of the blood and dialysate increases the concentration gradient between the blood and dialysate. The increased gradient helps to remove more potassium, phosphorus and urea from the blood. If we used parallel flow so less  concentration gradient of solutes is present and hence, less potassium, phosphorus and urea are removed from the blood

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