AP BIOLOGY

Detailed explanation-1: -In this practical, students use a potometer to measure the rate of transpiration. There are two main types of potometer used in schools – the mass potometer, which measures transpiration through the loss of mass, and the moving-bubble potometer, which measures water uptake by the shoot.

Detailed explanation-2: -Investigating transpiration Under normal circumstances, the rate of water uptake gives a measure of the rate of transpiration . A simple potometer is a piece of capillary tubing to which a plant has been connected. The water uptake is measured by recording the time taken for a bubble in the tube to move a set distance.

Detailed explanation-3: -A potometer is a device used to measure the rate of transpiration or the rate of loss of water from the leaves of a plant. Q. Ganong’s potometer is an instrument that is used to measure the rate of transpiration.

Detailed explanation-4: -Complete answer:Weighing method is a method to check transpiration in which a small lightweight potted plant can be weighed before and after the end of a certain period of time. The soil surface and the pot should be fully covered to prevent evaporation from the surfaces other than the plant.

Detailed explanation-5: -The rate of transpiration cannot be accurately determined using a potometer because all the water that is taken by the plant is not involved in transpiration. Also, potometer only measures the rate of uptake of water.