Under conditions of high temperature and drought stress, a plant closes its stomata to conserve water. Which of the following is the MOST DIRECT consequence on the Calvin cycle?
Increased photorespiration due to oxygen accumulation.
Enhanced ATP synthesis due to increased proton gradient.
Reduced availability of CO2 limits carboxylation, leading to a decrease in RuBP regeneration.
Increased activity of Rubisco due to higher substrate concentration.
Related Questions
How does water stress primarily affect the rate of photosynthesis?
By directly inhibiting chlorophyll production
By increasing the rate of photorespiration
By reducing stomatal opening, limiting CO2 uptake
By denaturing the enzymes involved in the Calvin cycle
Warburg effect is the
Inhibition of cycle by
Inhibition of cycle by
Inhibition of cycle by
Inhibition of cycle by
Compensation point refers to
Rate of photosynthesis = Rate of respiration
Rate of photosynthesis = Rate of splitting
Rate of photosynthesis = PGA formation
Rate of photosynthesis = RuBP formation
Water stress makes plant leaves …A… thus, …B… the surface area of leaves and their metabolic activity as well Here A and B refer to
A-wilt, B-increases
A-wilt, B-decreases
A-fall, B-decreases
A-fall, B-increases
A plant is exposed to green light only. Which of the following is most likely to occur?
The rate of photosynthesis will be significantly reduced.
The rate of photosynthesis will be at its maximum.
The rate of photosynthesis will be slightly increased.
The rate of photosynthesis will remain unaffected.
Which of the following combinations of factors would most likely result in the highest rate of photosynthesis?
Low light intensity, low temperature, and low CO2 concentration
High light intensity, low temperature, and high CO2 concentration
High light intensity, optimal temperature, and high CO2 concentration
Low light intensity, high temperature, and low CO2 concentration
Which of the following factors does NOT directly influence the rate of photorespiration?
Light intensity
Oxygen concentration
Temperature
Carbon dioxide concentration
How does an increase in atmospheric CO2 concentration initially affect the rate of photosynthesis, assuming other factors are optimal?
Increases the rate
Decreases the rate
Has no effect
Causes photorespiration
Which of the following statements is not correct regarding Blackman’s law of limiting factors ?
The process rate is always controlled by a single, unchanging factor.
When a biological process is affected by multiple factors, its rate is limited by the factor which is in least amount relative to its requirement
If a factor is limiting, increasing its concentration will increase the rate of the process
If a limiting factor's supply is increased, some other factor will eventually become limiting
Which of the following factors does NOT directly affect the rate of photosynthesis?
Light intensity
Carbon dioxide concentration
Temperature
Soil pH
