I: | It is the primary source of all food on earth. |
II: | It is responsible for the release of oxygen into the atmosphere by green plants. |
1. | Only I is correct |
2. | Only II is correct |
3. | Both I and II are correct |
4. | Both I and II are incorrect |
The factors that can be limiting for the light independent reactions of photosynthesis are:
1. , temperature, and light
2. , light, and water
3. water, temperature, and
4. oxygen, water, and temperature
Except for plants in shade or in dense forests, light is rarely a limiting factor in nature. This is because:
1. | Dark reactions do not depend on light |
2. | The rate of photosynthesis can be increased by higher carbon dioxide and lower temperatures even in low light conditions |
3. | Light saturation occurs at 10 % of full sunlight |
4. | Carbon fixation is independent of enzymes |
Statement I: | Despite the presence of a green leaf, optimal light and carbon dioxide conditions, the plant may not photosynthesize if the temperature is very low. |
Statement II: | If a chemical process is affected by more than one factor, then its rate will be determined by the factor which is nearest to its minimal value. |
1. | Both Statement I and Statement II are correct and Statement II explains Statement I |
2. | Both Statement I and Statement II are correct but Statement II does not explain Statement I |
3. | Statement I is correct but Statement II is incorrect |
4. | Statement I is incorrect but Statement II is correct |
Statement I: | Green house crops such as tomatoes and bell pepper are allowed to grow in carbon dioxide enriched atmosphere. This leads to higher yields. |
Statement II: | C3 plants respond to higher carbon dioxide concentration by showing increased rates of photosynthesis, leading to higher productivity. |
1. | Both Statement I and Statement II are correct and Statement II explains Statement I |
2. | Both Statement I and Statement II are correct but Statement II does not explain Statement I |
3. | Statement I is correct but Statement II is incorrect |
4. | Statement I is incorrect but Statement II is correct |
1. | 0.03 to 0.04 | 2. | 0.04 to 0.05 |
3. | 0.05 | 4. | more than 0.05 |
I: | Water stress can cause the stomata to close, hence, reducing the carbon dioxide availability. |
II: | Water stress also makes leaves wilt, thus, reducing the surface area of the leaves and their metabolic activity as well. |
1. | Only I | 2. | Only II |
3. | Both I and II | 4. | Neither I nor II |
Statement I: | Except for plants in shade or in dense forests, light is rarely a limiting factor in nature. |
Statement II: | There is a linear relationship between incident light and carbon dioxide fixation rates at low light intensities. |
1. | Both Statement I and Statement II are correct and Statement II explains Statement I |
2. | Both Statement I and Statement II are correct but Statement II does not explain Statement I |
3. | Statement I is correct but Statement II is incorrect |
4. | Statement I is incorrect but Statement II is correct |