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Some seeds require a specific duration of light exposure to germinate. If a flash of red light (R) is given, followed immediately by a flash of far-red light (FR), what is the MOST LIKELY effect on germination?
Germination will be stimulated.
Germination will be inhibited.
Germination will be unaffected.
The effect will depend on the seed species.
A researcher observes that a batch of dormant seeds fails to germinate even after scarification and exposure to favorable conditions. Suspecting the presence of a volatile inhibitor, which experimental setup is MOST appropriate to confirm this hypothesis?
Grind the dormant seeds and apply the extract to non-dormant seeds.
Place the dormant seeds in a closed container with non-dormant seeds of a different species and observe germination rates.
Expose the dormant seeds to high concentrations of ethylene gas.
Soak the dormant seeds in a solution of gibberellic acid.
In some plant species, seed dormancy is broken by the action of microorganisms in the soil. Which mechanism is MOST LIKELY involved in this process?
Microbial production of gibberellins that stimulate germination.
Microbial degradation of germination inhibitors in the seed coat.
Microbial enhancement of oxygen availability to the embryo.
Microbial scarification of the seed coat, allowing water imbibition.
A researcher observes that the growth rate of a plant significantly increases after the application of a specific hormone. Further analysis reveals that this hormone promotes cell elongation primarily in the intercalary meristem. Which hormone is most likely responsible for this observed growth?
Auxin
Cytokinin
Ethylene
Gibberellin
A particular mutation affects the synthesis of expansins in a plant species. Which of the following growth-related processes will be most directly impacted by this mutation?
Cell division in the meristem
Nutrient uptake from the soil
Photosynthetic efficiency
Cell wall loosening and expansion
Which of the following best describes the relationship between arithmetic growth and geometric growth in a typical organism's life cycle?
Arithmetic growth and geometric growth occur simultaneously.
Geometric growth always precedes arithmetic growth.
Arithmetic growth always precedes geometric growth.
Arithmetic growth often precedes or follows a period of geometric growth.
A plant exposed to unidirectional light exhibits phototropism. If the tip of the coleoptile is removed and replaced with a gelatin block, then illuminated from one side, which of the following will be observed?
The coleoptile will bend towards the light source.
The coleoptile will bend away from the light source.
The coleoptile will not bend towards the light source.
The coleoptile will exhibit random growth.
A seedling is placed horizontally on a rotating platform in the dark. Which of the following best describes the growth pattern of the seedling's root and shoot after a few days?
Both root and shoot will grow horizontally.
The root will grow upwards, and the shoot will grow downwards.
The root will grow downwards, and the shoot will grow upwards.
Both root and shoot will grow in a random direction.
A biennial plant requiring vernalisation is induced to flower after prolonged exposure to low temperatures. However, immediately after this cold treatment, if the plant is exposed to a brief period of high temperatures, the effect of vernalisation is nullified. This phenomenon is known as:
Devernalisation
Stratification
Photoperiodism
Vernalisation reversal
