Transpiration
Biology: Edexcel IGCSE, topic 3.3.5
Transpiration
Transpiration is the evaporation of water vapour from the leaves of plants. This is what drives water to be drawn up from the roots, up the stem, to the leaves.
Root hair cells
- Root hair cells absorb water from the soil via osmosis.
- Mineral ions are taken up by active transport.
Xylem
- After being absorbed by the root hair cells, the water and minerals are transported in xylem vessels.
- Water molecules in the xylem stick together, drawing water up the stem.
Leaves
- Once it reaches the leaves, the majority of water evaporates and the water vapour diffuses out (is lost) through open stomata.
- This loss of water from the leaves is known as transpiration and is the force that pulls water up from the roots.
Test yourself on Transpiration
By what process are mineral ions taken up by plants?
What is the technical term for the evaporation of water vapour from plant leaves?
Absorption in root hair cells