Plant Nutrition Flashcards
Photosynthesis balanced equation
6CO2 + 6H2O –> C6H12O6 + 6O2
Photosynthesis word equation
Carbon dioxide + water –> glucose + oxygen
—> = light and chlorophyll
Where does photosynthesis happen
Leaves of plant
Why are leaves green
They reflect green light and absorb red blue and white
What absorbs light
Chlorophyll in chloroplasts in the plant cells
Leaf functions
Carry out photosynthesis
Get rid of waste products of photosynthesis
Export glucose to rest of plant
Waxy cuticle
Waterproof
Reduces water loss
Reduces infection
Upper epidermis
Protection
No chloroplasts
Absorbs harmful light but allows light for PS pass through
Palisade cells
Tightly packed
Elongated
Lots of chloroplasts
High rate of PS
Spongy s
Some chloroplasts
Some PS
Loosely packed with air spaces
Air spaces
Between spongy cells
Provide air channels allowing gas exchange
Leaf vein- xylem
Rigid vessels within lignin
Carry water and minerals from root to stem to leaf
Made of dead cells
Leaf vein- phloem
Responsible for carrying sugars to places where glucose is stored as starch
Guard cells
Change shape depending on water inside
Controls opening of stomata
For transpiration
Stomata
Space between guard cells
Controls gas exchange and water loss
Adaptations for PS
Air spaces
Palasides
Xylem
Adaptations for importing raw materials
Air spaces
Xylem
Upper epidermis
Adaptations for waste products
Air spaces
Stomata
Adaptations for movement of materials in plant
Phloem
Tropism
The growth response of a plant to directional stimulus
Tropisms
Phototropism- shoots grow toward light (positive) and roots mostly neutral, sometimes negative
Geotropism- shoots grow away from gravity (negative) and roots grow toward (positive)
Hydrotropism- roots grow toward source (positive)
Thigmotropism- shoots bend round support (positive) and roots grow away from objects (negative)
Auxin
Hormone which diffuses from top of plant
Shoot bends toward light
More hormones diffuse to dark side of plant so it grows longer
Limiting factors of photosynthesis
Light intensity
Carbon dioxide concentration
Temperature
Water concentration
Light intensity
Without enough light a plant can’t photosynthesis even if there is enough water or CO2, increasing light intensity will boost the rate of photosynthesis
Carbon dioxide concentration
Plant can’t photosynthesis with enough CO2 even if it has sufficient everything else