plants and water Flashcards
(31 cards)
What percentage of water constitutes active plant tissue?
70-95%
Active plant tissue is highly dependent on water for its structure and function.
What is required for plants to grow?
Turgidity
Turgidity is the state of being swollen or distended, which is essential for plant growth.
How does a plant use water?
For biochemical reactions, growth, maintaining turgor, and as a solvent for nutrient transport
Water is crucial for photosynthesis and nutrient transportation in plants.
Through which part of the plant does water enter?
Roots
How does water exit a plant?
Through stomata via transpiration
Transpiration is the process of water vapor loss from plant leaves.
What is the transpiration stream?
Movement of water and water-soluble minerals through the plant via the xylem
List the functions of transpiration.
- Transport of nutrients
- Temperature control
- Functional biochemistry
- Provides energy for water movement
Transpiration is vital for nutrient transport and regulating leaf temperature.
Is water flow in plants a passive or active system?
Passive system
What drives water flow in plants?
Water potential differences
What are the four main compartments of the water transport system?
- Soil
- Root
- Shoot
- Atmosphere
How is ion uptake by root cells primarily characterized?
Active and requires energy
Ion uptake is necessary for nutrient absorption from the soil.
What mechanism facilitates faster water uptake in plants?
Aquaporins
Aquaporins are specialized transport proteins that enhance water movement across membranes.
What are the three pathways for water transport in plants?
- Apoplast
- Symplast
- Transmembrane pathway
What is the function of xylem?
Carries water and minerals upwards from root to the rest of the plant
What is the primary component of the phloem?
Sieve tubes
Sieve tubes are living cells that conduct sugars and nutrients.
What causes water vapor to leave the leaves?
Evaporation through stomata
What is the primary function of stomata?
Regulate water loss and allow CO2 to diffuse into the leaf
What drives transpiration in plants?
Difference in pressure of water vapor
What happens to water loss resistance when stomata open?
Resistance decreases
What causes guard cells to open stomata?
Absorption of water and swelling
What is the CO2 feedback loop in stomatal action?
- Light promotes photosynthesis
- Lowers CO2 levels in the leaf
- K+ moves into guard cells
- Stomata open
What triggers the H2O feedback loop in stomatal action?
Water stress
Define water potential.
Measure of the ability of water molecules to move freely in solution
