chap 6- Plant nutrition Flashcards
Photosynthesis
- Process plants use to produce carbohydrates
- Uses energy from light
equation for photosynthesis?
- Carbon dioxide + Water —> Glucose + Oxygen
- Requires light and chlorophyll
- 6CO2 + 6H20 —> C6H12O6 + 6O2
What is the function of chlorophyll?
- Transfers light energy to chemical energy
- Energy produced used for the synthesis of carbohydrates
Limiting factor
- Something in such short supply it restricts life processes
- E.g. light, carbon dioxide, water
What factors can limit photosynthesis?
- Sunlight in cloudy/dark places
- Water in dry places
- Temperature in too hot or too cold conditions
- Carbon dioxide
How can photosynthesis be optimized in temperate or tropical countries?
- Use a glasshouse to control variables
- In a cold country, increase the temperature to the optimum level
- In a dry environment, increase the humidity/water available
- Ensure optimum light using electric lighting
- Choose plant species that suit the environment
- Use automatic systems to control variables
palisade mesophyll adaptation
packed to maximise light absorption, contain lots of
chloroplasts
Chloroplasts adaptation:
can move to maximise absorption of light
Waxy cuticle / Upper epidermis adaptation
transparent to allow light to reach chloroplasts, waxy to
prevent evaporation of water and stops pathogen entry
Air spaces in spongy mesophyll -adaptation
allow gases to diffuse
Xylem adaptation
allows entry of water and mineral ions by transpiration stream
Guard cells adaptation
control opening and closure of stomata
Stomata adaptation
allow carbon dioxide to enter, oxygen and water to leave
Leaf shape:
thin and broad (large surface area)
What is the importance of nitrate ions for amino acids?
- Amino acids contain nitrogen
- Amino acids form proteins
- Deficiency causes stunting, weakness, yellowing
