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B4: Quiz 3 – Answers
B4: Quiz 3 – Answers
1)
a) Light intensity, concentration of carbon dioxide and temperature
b) A limiting factor is where the rate of photosynthesis will not increase unless the limiting factor is increased/ a limiting factor is limiting the rate of photosynthesis/ a limiting factor is stopping the rate of photosynthesis from increasing
2)
a) 3.5 arbitrary units (±0.5)
b) 6 arbitrary units (±0.5)
c) The curve for 30°C levels off at a higher rate of photosynthesis than the curve for 15°C. This tells us that temperature must be the limiting factor when the 15°C curve becomes flat
3) The only difference between the two conditions is the concentration of carbon dioxide; for the blue line the concentration is 0.02% and for the green line the concentration is 0.2%. The green line becomes flat at a higher rate of photosynthesis, which means that the concentration of carbon dioxide must be the limiting factor for the blue line (concentration of carbon dioxide of 0.02% and a temperature of 20°C)
4) The limiting factor cannot be temperature because the curves for 20°C and 30°C are exactly the same. Also, the limiting factor cannot be the concentration of carbon dioxide because for the flat parts of both of the curves, the rate of photosynthesis remains unchanged when we increase the concentration of carbon dioxide. Therefore, light intensity must be the limiting factor when both of the curves are flat
a) Light intensity, concentration of carbon dioxide and temperature
b) A limiting factor is where the rate of photosynthesis will not increase unless the limiting factor is increased/ a limiting factor is limiting the rate of photosynthesis/ a limiting factor is stopping the rate of photosynthesis from increasing
2)
a) 3.5 arbitrary units (±0.5)
b) 6 arbitrary units (±0.5)
c) The curve for 30°C levels off at a higher rate of photosynthesis than the curve for 15°C. This tells us that temperature must be the limiting factor when the 15°C curve becomes flat
3) The only difference between the two conditions is the concentration of carbon dioxide; for the blue line the concentration is 0.02% and for the green line the concentration is 0.2%. The green line becomes flat at a higher rate of photosynthesis, which means that the concentration of carbon dioxide must be the limiting factor for the blue line (concentration of carbon dioxide of 0.02% and a temperature of 20°C)
4) The limiting factor cannot be temperature because the curves for 20°C and 30°C are exactly the same. Also, the limiting factor cannot be the concentration of carbon dioxide because for the flat parts of both of the curves, the rate of photosynthesis remains unchanged when we increase the concentration of carbon dioxide. Therefore, light intensity must be the limiting factor when both of the curves are flat
Questions
1)
a) What are the three main factors that affect the rate of photosynthesis?
b) What is a limiting factor?
2) The graph below has light intensity on the x axis and the rate of photosynthesis on the y axis. One of the curves is drawn for a temperature of 15°C and the other curve is drawn for a temperature of 30°C.
1)
a) What are the three main factors that affect the rate of photosynthesis?
b) What is a limiting factor?
2) The graph below has light intensity on the x axis and the rate of photosynthesis on the y axis. One of the curves is drawn for a temperature of 15°C and the other curve is drawn for a temperature of 30°C.
a) For the 15°C curve, when does light intensity stop being a limiting factor? Give your answer in arbitrary units.
b) For the 30°C curve, when does light intensity stop being a limiting factor? Give your answer in arbitrary units.
c) For the 15°C curve, what is the limiting factor when the curve becomes flat? Explain your answer.
3) The graph below has light intensity on the x axis and the rate of photosynthesis on the y axis. One of the curves is for a concentration of carbon dioxide of 0.2% and a temperature of 20°C (green line), and the other curve is for a concentration of carbon dioxide of 0.02% and a temperature of 20°C (blue line).
b) For the 30°C curve, when does light intensity stop being a limiting factor? Give your answer in arbitrary units.
c) For the 15°C curve, what is the limiting factor when the curve becomes flat? Explain your answer.
3) The graph below has light intensity on the x axis and the rate of photosynthesis on the y axis. One of the curves is for a concentration of carbon dioxide of 0.2% and a temperature of 20°C (green line), and the other curve is for a concentration of carbon dioxide of 0.02% and a temperature of 20°C (blue line).
The curve for a concentration of carbon dioxide of 0.02% and a temperature of 20°C becomes flat at around a light intensity of 10 arbitrary units; what is the limiting factor for these conditions when the curve becomes flat? Explain your answer.
4) The graph below has the concentration of carbon dioxide on the x axis and the rate of photosynthesis on the y axis. The curves for a temperature of 20°C (green) and 30°C (blue) look exactly the same.
4) The graph below has the concentration of carbon dioxide on the x axis and the rate of photosynthesis on the y axis. The curves for a temperature of 20°C (green) and 30°C (blue) look exactly the same.
The three factors that affect the rate of photosynthesis are light intensity, concentration of carbon dioxide and temperature. When both the 20°C and 30°C curves become flat, what must be the limiting factor? Explain why the other factors cannot be the limiting factor.