Factors Affecting Photosynthesis Flashcards
How do limiting factors affect photosynthesis?
Limiting factors such as light intensity, carbon dioxide concentration and temperature determine the rate of photosynthesis. Only improving the limiting factor will increase the rate of the process
Why does changing non-limiting factors not alter the rate of photosynthesis?
Non - limiting factors are already at levels sufficient to sustain the process, so altering them will not overcome the limitation imposed by the limiting factor
Give three common limiting factors for photosynthesis and their effect on the process
- Light intensity - affects the light dependent reactions
- Carbon dioxide concentration - prevents the calvin cycle from fully functioning
- Temperature - affects enzyme activity in photosynthesis
What happens to the rate of photosynthesis if the limiting factor is improved?
The rate of photosynthesis will increase until another factor becomes limiting
Explain why temperature can be a limiting factor in photosynthesis
Photosynthesis relies on enzymes that function optimally at specific temperatures. Low temperatures reduce enzyme activity, while high temperatures can denature enzymes
How does the concept of limiting factors apply in agricultural practices?
Farmers optimize conditions such as light, temperature and carbon dioxide concentration in greenhouses to minimize limiting factors and maximize crop growth
What happens to the rate of photosynthesis when light is the limiting factor?
The rate of photosynthesis is directly proportional to light intensity when light is the limiting factor
What occurs when light intensity increases beyond the light compensation point?
The rate of photosynthesis increases proportionally with light intensity, leading to greater volumes of oxygen released and carbon dioxide absorbed
What is the light compensation point?
The light compensation point is the light intensity at which the volume of oxygen produced and carbon dioxide absorbed during photosynthesis equals the volume of oxygen absorbed and carbon dioxide produced
What happens when light intensity is no longer the limiting factor?
The rate of photosynthesis will plateau, and further increases in light intensity will have no effect because another factor, such as carbon dioxide concentration or temperature, becomes limiting
What is the relationships between oxygen production and carbon dioxide absorption during photosynthesis at different light intensities?
At low light intensities, oxygen production and carbon dioxide absorption are low
At the light compensation point, oxygen production equals oxygen absorption, and carbon dioxide absorption equals carbon dioxide production
Beyond the light compensation point, both oxygen production and carbon dioxide absorption increase proportionally with light intensity until another factor becomes limiting
Why does photosynthesis plateau at high light intensities?
At high light intensities, other factors, such as carbon dioxide concentration. or temperature, limit the rate of photosynthesis, preventing further increases
Why is carbon dioxide often the limiting factor for photosynthesis under normal conditions?
The concentration of carbon dioxide is relatively low, which limits the rate at which it can be used in the light - independent reaction of photosynthesis
How does carbon dioxide concentration affect the enzyme activity in photosynthesis?
Carbon dioxide concentration affects the activity of the enzyme rubisco, which catalyses the reaction between ribulose bisphosphate and carbon dioxide in the light - independent reaction
Why does increasing carbon dioxide concentration enhance the light - independent reaction?
Higher carbon dioxide concentrations increase the availability of substrate for rubisco, accelerating the rate at which RuBP combines with carbon dioxide to form glycerate 3-phosphate (GP)
