How does the root absorb water and mineral salts1

Apuntes

• Subtopic: How Roots Absorb Water and Mineral Salts Structure of Roots As you observed in investigative activity 1, the roots of the onion have numerous tiny hairs protruding from them. These are called root hairs. The root hairs grow outward into the spaces between the soil particles, where there is water with dissolved mineral salts. A root hair contains root hair cells. • Subtopic: Movement of Water and Mineral Salts Water is drawn up by the root hair cells by moving from a region with higher water content (the soil) to a region of lower water content (inside the roots). No energy is needed for this process. A root hair cell has a long, hair-like structure. This structure allows the root hair to have a large surface area, so water can be absorbed through the root hairs at a higher rate. However, for the absorption of mineral salts, energy is required. During absorption, water and mineral salts first enter the root hair cell. Then, they move into the neighboring root cells until they reach the transport tissues in the roots.