When the concentration of water is the same on both sides of a membrane there is no net movement. This is shown on a graph where the trendline crosses the x-axis. What is this point called?

The point where the concentration of water molecules is the same on both sides of a membrane and therefore there is no net movement is called ISOTONIC POINT.

In conclusion, the point where the concentration of H2O molecules is the same on both sides of a biological membrane is called the ISOTONIC POINT.

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Answer

The point where the concentration on both sides of a membrane is equal to each other is called the Isotonic Point.

Explanation:

The result is that osmosis cannot or stops to occur. For net water movement to occur, the solution on one side of the membrane needs to have a higher concentration than the other.

isotonicity can also occur between two membranes when due to the process of Osmosis, the concentration on both sides of of the membrane have equalised.

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option c is the correct answer.