Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
A dormant seed of a desert plant exhibits an extremely low metabolic rate. Which of the following biochemical changes contributes MOST significantly to this state?
Increased gibberellin biosynthesis and rapid cell division
High abscisic acid (ABA) levels and dehydration of cellular components
Elevated ethylene production and fruit ripening processes
Increased cytokinin concentration and enhanced protein synthesis
Certain seeds require a period of cold exposure before germination, a process known as stratification. This requirement primarily ensures:
Increased seed coat permeability to oxygen solely
Activation of enzymes responsible for nutrient mobilization only
Leaching of germination inhibitors and promotion of gibberellin biosynthesis
Vernalization of the embryo and subsequent flowering
A plant with a mutation affecting its abscisic acid (ABA) receptors is exposed to drought conditions. Which would be the LEAST likely observation?
Reduced transpiration
Increased leaf wilting
Reduced root growth
Increased expression of drought-responsive genes
A researcher studying secondary growth in a dicot stem observes a peculiar pattern. The vascular cambium appears to be producing more xylem towards the center than phloem towards the periphery. Which of the following factors is LEAST likely to contribute to this unusual observation?
Hormonal imbalances
Environmental stress
Genetic mutation
Seasonal variations
Which micronutrient is essential for the synthesis of auxin, a plant hormone crucial for growth and development?
Copper
Molybdenum
Zinc
Boron
Zinc is essential for the activity of which plant hormone?
Gibberellin
Cytokinin
Auxin
Ethylene
A dormant seed of a desert plant imbibes water but fails to germinate even under optimal temperature and oxygen availability. Which of the following is the MOST LIKELY explanation for this continued dormancy?
Insufficient light exposure to trigger phytochrome conversion.
Presence of inhibitors like abscisic acid in the seed coat.
Immature embryo requiring a period of after-ripening.
Hard seed coat impermeable to oxygen, preventing respiration.
Which plant hormone promotes seed dormancy?
Gibberellin
Auxin
Cytokinin
Abscisic acid (ABA)
Which of the following is NOT a method used by plants to overcome seed dormancy?
Scarification of the seed coat
Stratification or exposure to low temperatures
Exposure to high concentrations of abscisic acid
Leaching of inhibitory substances
Which of the following is an example of a chemical inhibitor that can cause seed dormancy?
Gibberellins
Cytokinins
Abscisic acid
Ethylene