Prepare for NEET with Botany-specific practice questions. Covering all major Botany chapters, this is perfect for your NEET Biology needs.
In a hypothetical plant species, the inflorescence exhibits a unique combination of features: a condensed cymose head surrounded by an involucre of brightly colored bracts that mimic petals. The individual flowers within the head are inconspicuous. Which existing inflorescence type does this MOST closely resemble, and what evolutionary advantage might this unique structure offer?
Cyathium; protection from herbivores
Hypanthodium; trap for pollinators
Capitulum; enhanced pollinator attraction
Verticillaster; increased seed dispersal
Differentiating between a thyrse and a mixed inflorescence can be challenging. Which of the following statements BEST distinguishes a thyrse from a truly mixed inflorescence?
A thyrse always has a determinate main axis, while a mixed inflorescence always has an indeterminate main axis.
A thyrse has a cymose arrangement of racemose units, while a mixed inflorescence combines different inflorescence types randomly.
A thyrse always has brightly colored bracts, while a mixed inflorescence lacks bracts.
A thyrse has a racemose arrangement of cymose units, while a mixed inflorescence combines different inflorescence types in a less predictable pattern.
Which of the following experimental manipulations would MOST effectively demonstrate the contribution of root pressure to xylem sap ascent in a small herbaceous plant?
Submerging the roots in a hypertonic solution and observing changes in leaf turgor
Measuring the rate of transpiration under varying light intensities
Removing the apical bud and observing the effect on guttation
Measuring exudation rate from a cut stem stump after applying a respiratory inhibitor to the roots
The primary mechanism for xylem sap ascent in tall trees is transpiration pull. However, root pressure plays a minor role. Which statement BEST describes the limited contribution of root pressure to overall xylem sap ascent in tall trees?
Root pressure generates excessive pressure that could damage the delicate xylem tissues in tall trees.
Root pressure is only active during the night and therefore cannot contribute to daytime transpiration.
Tall trees have a significantly lower root surface area to volume ratio, minimizing the contribution of root pressure.
Root pressure can only push water a limited height due to the opposing force of gravity and the relatively low pressure generated.
