Question

Where does transpiration cohesion pull theory work?
A. Active absorption
B. Inactive absorption
C. Active and inactive absorption
D. None of these

Answer 1

Hint: The absorption in plants includes both active and inactive absorption. In passive absorption, the transpiration pull is responsible for the upward flow of water through the roots. Cohesion force between water molecules keeps the flow of water continuous and intact. Active absorption refers to the absorption of water using root cells.

Complete step by step answer: Absorption of water in plants takes place by two processes that are active absorption and passive absorption. Passive absorption is also called inactive absorption. The absorption of water by root cells with the help of ATP, generated by the process of root respiration is called active absorption. It is so-called because the root cells of the plant actively take part in this process. Active absorption is further classified into active osmotic absorption and active non-osmotic absorption. Therefore, the root cells are responsible for the active absorption of water in plants. In inactive or passive absorption metabolic energy is not required for the utilization of water. Transpiration pull is created at the leaf end and is responsible for the upward flow of water in plants. Here, roots cells are not involved in the process of absorption. Due to the cohesion between the molecules, the continuity of the water column remains intact.
Hence, Option B: inactive absorption is the correct answer as the transpiration cohesion pull theory is seen in inactive absorption of water.

Note: The passive transport is the same as diffusion involves free movement of molecules from their higher concentration to their lower concentration and does not require input energy. Diffusion facilitated diffusion, and filtration is another type of passive absorption.