Transpiration
Transpiration is the loss of water vapour from plant surfaces, mainly through stomata, playing a crucial role in water transport and cooling
Core concept
Stomata, tiny pores mainly on leaf surfaces, open and close to regulate transpiration, controlled by the turgidity of surrounding guard cells.
How it works
Transpiration creates a 'pull' (transpiration pull) that helps draw water upward through the xylem from roots to leaves, aiding water transport.
Why it matters
Factors affecting transpiration rate include temperature, humidity, wind speed, and light intensity, all altering the rate of water loss.
Key detail
Transpiration also helps cool the plant, similar to sweating in humans, preventing overheating during high temperatures.
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Quick notes
• Stomata: pores mainly on leaves, regulate transpiration.
• Guard cell turgidity controls stomata opening/closing.
• Transpiration creates a 'pull' effect.
• This pull draws water up through xylem.
• Factors: temperature, humidity, wind, light.
• These affect the rate of transpiration.
• Transpiration cools the plant.
• This is similar to sweating in humans.