Section 3 - Plant Nutrition and Transport Flashcards
Photosynthesis
chemical reaction where carbon dioxide and water react using light energy to produce glucose and oxygen
Equation for photosynthesis
carbon dioxide + water → glucose + oxygen
6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂
What is glucose converted into
1) starch
2) used for respiration (only at night)
3) protein for growth
4) cellulose for cell wall
5) fats and oils
Why does plant store extra glucose as starch?
Starch is insoluble and so cannot be transported around the plant; this stops the glucose from dissolving into the cytoplasm and the vacuole.
Wax cuticle
the outer surface of the leaf which prevents water loss
Upper/Lower epidermis
tough layer that protects the leaf; transparent so light can penetrate the leaf
Palisade mesophyll
vertical, which can fit more cells, and has lots of chloroplasts
Spongy mesophyll
air spaces allowing oxygen and carbon dioxide to exchange
Guard cell
controls if the stomata is open or closed
Stomata
Tiny holes within the epidermis. Oxygen, carbon dioxode and water gets in and out.
Why is the leaf places into ethanol when testing for starch?
to kill the chloroplasts
Why is the leaf placed into boiling water when testing for starch?
to denature the enzymes
Limiting factor
the component of the reaction that is in ‘shortest supply’ so that it prevents the rate of reaction increasing
What are the three limiting factors of photosynthesis?
1) light intensity
2) CO₂ concentration
3) temperature
Role and deficiency symptoms of nitrates in plants
Role:
Contains nitrogen to make amino acid and proteins. Needed for cell growth.
Deficiency symptoms:
stunted growth, yellow older leaves
