This deep dive covers Plant Adaptations to Control Water Loss within Transpiration for GCSE Biology. Transpiration process, stomatal control, factors affecting rate, plant adaptations, measuring transpiration, and practical investigations It is section 7 of 20 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 7 of 20
Practice
20 questions
Recall
25 flashcards
Plant Adaptations to Control Water Loss
Xerophytes (Desert Plants)
Xerophytes are adapted to survive in dry conditions with limited water:
Structural adaptations:
- Thick waxy cuticle: Waterproof barrier reducing evaporation
- Sunken stomata: Protected in pits, trapping humid air
- Reduced leaves/spines: Minimal surface area for water loss
- Rolled leaves: Creates humid microclimate (marram grass)
- Hairy leaves: Trap moisture, reduce air movement
- Succulent stems: Store water (cacti)
Physiological adaptations:
- CAM photosynthesis: Stomata open at night, closed during day
- Deep roots: Access groundwater
- Reduced stomatal density: Fewer stomata per unit area
Hydrophytes (Water Plants)
Hydrophytes have opposite adaptations for aquatic life:
- Thin/no cuticle: No need for waterproofing
- Many stomata on upper surface: Maximum gas exchange
- Large air spaces: Buoyancy and gas storage
- Flexible stems: Bend with water currents
- Large surface area: Maximum absorption
Case Study: Marram Grass
Marram grass (beach grass) shows multiple xerophytic features:
- Rolled leaves: Curl inward in dry conditions
- Sunken stomata: Located in grooves on inner surface
- Hairs in grooves: Trap humid air near stomata
- Thick cuticle: Reduces cuticular transpiration
- Result: Can survive on sand dunes with minimal water