NEET Botany - MCQ Practice Questions

The rate-limiting step of photosynthesis under normal conditions is:

Which of the following best describes the Pasteur effect?

Which statement about ATP synthase is correct?

A plant is kept in a chamber with elevated CO2 concentration (800 ppm) and saturating light. What will be the most likely effect on the RuBP level in the stroma?

In the absence of light, what happens to the pH gradient across the thylakoid membrane?

Which photosystem has a lower reduction potential for its reaction center chlorophyll (P700 vs P680)?

The Emerson effect demonstrates that photosynthesis efficiency increases when plants are exposed to both red and far-red light together compared to either alone. This is explained by:

During the S-state transitions in the oxygen-evolving complex, the manganese cluster undergoes sequential oxidation. How many oxidation steps occur before O2 is released?

A research study on stomatal regulation shows that ABA (abscisic acid) concentration increases 100-fold in guard cells during drought stress. Which of the following correctly describes the mechanism?

Which of the following statements about pollen grains is INCORRECT?

In apomixis, seeds are produced without:

The phenomenon where a single plant produces both male and female flowers is called:

Which stage of meiosis in microsporogenesis ensures genetic variation in pollen grains?

Identify the correct sequence in the development of male gametophyte:

The endothecium in the anther wall is important for:

The phenomenon where pollen grains retain viability after being kept in dry conditions for extended periods is called:

In a typical angiosperm flower, after dehiscence, the mature pollen is released at which stage?

In orchids, the lack of endosperm development is compensated by:

The phenomenon of pollen dimorphism is observed in which type of flowers?

Which of the following represents the correct ploidy level progression during the life cycle of a typical angiosperm?