Question

Define root pressure. How would you demonstrate it experimentally?

Answer 1

Root pressure is a type of positive hydrostatic pressure that is created inside the xylem by the cells of the roots, as a result of which the cell sap rises upwards through the stem.
It can be demonstrated by using a device called a manometer. It measures the pressure of exodus from the cut stems, which is directly equal to the root pressure. As the plant is watered, the roots absorb water from the soil. The turgid roots now start exerting pressure on the cells above, and push the water upward. This positive push is root pressure, which is proved by the movement of mercury in the manometer column.