B8 Flashcards
What is photosynthesis?
carbon dioxide + water - glucose + oxygen
6CO2 + 6H2O-C6H12O6+6O2
Endothermic reaction which releases oxygen and glucose
How are leaves well adapted?(4)
1.They are broad so they have a good surface area for light
2.Thin so diffusion is easy
3.Air spaces, allowing carbon dioxide to get into the cells and oxygen to leave the leaf
4.They contain chlorophyll in the chloroplasts to absorb light
How does light affect the rate of photosynthesis?
It can’t take place with little light but with lots, photosynthesis will be done quicker.
How does temperature affect photosynthesis?
As the temperature rises the rate of photosynthesis rises until as it is controlled by enzymes they become denatured so the rate of photosynthesis will fall.
How does carbon dioxide affect photosynthesis?
It is usually the limiting factor, especially in the day however at night it increases due to it not photosynthesising.
How does chlorophyll affect photosynthesis?
If it is limited in any way photosynthesis will be limited however in some plants with not green leaves they will be limited.
How do minerals affect the rate of photosynthesis?
If a plant does not have enough minerals, especially magnesium it cannot make chlorophyll so it cannot photosynthesise so it will die.
How to calculate light intensity?
light intensity=1/distance^2
Where is starch found?
It is stored in the cells of the leaves, providing an energy store for when it is dark. It is also kept in other special storage areas of a plant such as a potato.
What do plants and algae make from starch?
They make glucose, turning to amino acids by combining sugar, nitrate ions and other mineral ions.
How do plants make lipids?
They use some of the glucose from photosynthesis and energy from respiration to build up fats and oils to be used as an energy store, making cell walls stronger or as an energy store in seeds.
