With the help of information from the chapter, explain how water is transported from the roots to the leaves in tall plants.
Generated by claude-sonnet-4-6 · 2026-06-15 06:43 · grounding rag
Model Answer
Transport of Water from Roots to Leaves in Tall Plants:
- Absorption by roots: Root hair cells absorb water from the soil by osmosis. The large surface area of root hairs increases the efficiency of absorption.
- Movement across root: Water moves from root hair cells into the root cortex and then into the xylem vessels present in the root.
- Role of xylem: Xylem is the vascular tissue responsible for the transport of water and dissolved minerals from roots to all parts of the plant, including leaves.
- Transpiration pull: Water evaporates from the leaves through stomata — a process called transpiration. This creates a suction force (transpiration pull) that pulls water upward continuously through the xylem.
- Cohesion of water: Water molecules are held together by cohesive forces, forming a continuous water column in the xylem from roots to leaves.
Thus, water travels upward against gravity through a combination of root pressure, capillary action, and transpiration pull.
Source: Chapter 5, Transportation in Plants
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Explanation
- The examiner expects you to cover: root absorption → xylem pathway → transpiration pull as the driving force. These are the key steps for full marks.
- Mention xylem by name — it's directly tested in the MCQs of this chapter ("The xylem in plants are responsible for transport of water").
- Transpiration pull is the most important mechanism for tall plants; always name it explicitly.
- Do not confuse xylem (water transport) with phloem (food transport) — a common error that costs marks.