17.4 Factors affecting photosynthesis Flashcards
How does light intensity affect GP/ glycerate 3-phosphate
Low light means that there is a reduced amount of the products of the light dependent stage that are made (ATP & NADPH) so GP is made but not converted into TP
How does temperature affect GP/ glycerate 3-phosphate
Very low temperature means reactions are slower due to enzymes and too high temperatures will denature the enzymes
How does CO2 concentration affect Gylcerate 3-phosphate
At low concentrations their is less CO2 to combine with RuBP to make GP so GP levels will fall
How does light intensity affect triose phosphate TP
Low light means levels will fall as GP can’t be converted into TP without products from the light dependent reaction
How does temperature affect triose phosphate TP
Very low temperature means reactions are slower due to enzymes and too high temperatures will denature the enzymes
How does CO2 concentration affect triose phosphate TP
If GP is too low then it’s conversion to TP is also low (as there’s less CO2 to combine with RuBP to make GP)
How does light intensity affect Ribulose Biphoshate RuBP
If it’s too low the levels will fall as it used up making GP but not being made as quickly
How does temperature affect Ribulose Biphosphate RuBP
Very low temperature means reactions are slower due to enzymes and too high temperatures will denature the enzymes
How does CO2 concentration affect Ribulose Biphosphate RuBP
At too low concentrations RuBP is being made and not used up as CO2 can’t be combined with RUBP to make GP so RUBP levels will rise
On a graph for rate of photosynthesis again light intensity or CO2 when the graph plateaus what does this mean
Another factor is the limiting reactant eg temp
How can pollution affect photosynthesis
Industrial gases can damage leaves and block the stomata
can chlorophyll limit the rate of photosynthesis
Not usually but disease, senescence and a lack of minerals can affect it
How can water affect the rate of photosynthesis
A deficiency can lead to wilting and reduced crop yields, when stomata close to prevent H2O loss it also means CO2 can get in
