PhotosynthesisEdexcel GCSE Biology: Flashcards

Card 1 of 150 of 15 known

Question

Producers described as?

Tap or press Space to reveal

Tap card or press Space to flip

See all 15 cards

Producers described as?: Main producers of food and therefore biomass.
Endothermic or exothermic?: Endothermic — takes in light energy.
Word equation for photosynthesis?: Carbon dioxide + water → (light) → glucose + oxygen.
Balanced symbol equation?: 6CO2 + 6H2O → C6H12O6 + 6O2.
Three limiting factors?: Temperature, light intensity, CO2 concentration.
What is a limiting factor?: A factor in shortest supply restricting rate.
Effect of very high temperature on rate?: Falls sharply as enzymes denature.
Why do growers control temp/light/CO2 together?: Improving one alone is wasted once another becomes limiting.
How is rate measured in the pondweed practical?: Bubbles per minute or gas volume with a syringe.
Which variables must be controlled in the practical?: Temperature and CO2 concentration.
Rate vs light intensity relationship?: Directly proportional (while light is limiting).
Light intensity vs distance relationship?: Inversely proportional to distance squared.
Doubling distance from lamp: effect on intensity?: Falls to one quarter.
Why is gas syringe better than bubble counting?: Bubbles vary in size; syringe gives accurate volume.
By-product of photosynthesis?: Oxygen.