AP BIOLOGY

Detailed explanation-1: -Figure 2: Root hairs often form on fine roots and improve water absorption by increasing root surface area and by improving contact with the soil.

Detailed explanation-2: -In higher plants, water is absorbed through root hairs from the soil water. The walls of root hairs are permeable to water and are hydrophilic in nature. They contain vacuoles filled with cell sap. Absorption of water by roots takes place by two mechanism namely, active absorption and passive absorption.

Detailed explanation-3: -So the correct answer is Water absorption through roots can be increased by keeping the plants under the fan. When plants are kept under the fan, the rate of evaporation of water is increased resulting in the rapid increase in the process of transpiration.

Detailed explanation-4: -Because root hairs have an expanded structure, there is more surface area available for water absorption. Since root hair is hydrophilic and porous, it actively and passively takes water from the gaps between soil particles.