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.
A rare orchid species exhibits a highly specialized pollination mechanism. Its labellum mimics the pheromones and appearance of a specific female wasp species, attracting the males for pseudocopulation. Which of the following floral adaptations is LEAST likely to be observed in this orchid?
Abundant nectar production within the spur
Precise positioning of pollen packets (pollinia) for attachment to the male wasp
Flower color and shape closely resembling the female wasp
Flowering period synchronized with the mating season of the wasp
A mutant plant exhibits stunted root growth and reduced gravitropic response. Microscopic analysis reveals disorganized columella cells in the root cap. Which of the following is the MOST likely cause of this phenotype?
Increased production of cytokinin in the root tip
Disruption of amyloplast sedimentation and auxin redistribution
Overexpression of genes involved in cell elongation
Enhanced sensitivity to ethylene
The polyphyletic grouping of organisms is based on:
Shared ancestral characteristics.
Homologous characteristics derived from a common ancestor.
Analogous characteristics due to convergent evolution.
A combination of ancestral and derived characteristics.
A scientist is constructing a phylogenetic tree using cladistics. Which type of character would be considered the most informative for resolving evolutionary relationships within a group?
Plesiomorphy
Symplesiomorphy
Autapomorphy
Synapomorphy
A unique characteristic of the pomes like apple and pear is the fleshy edible part developing from:
Hypanthium
Ovary wall
Receptacle
Mesocarp
A composite fruit developing from a hollow, fleshy inflorescence axis is known as a:
pepo
syconus
drupe
hesperidium
Which of the following is NOT a characteristic feature exclusively found in prokaryotic 70S ribosomes?
Presence of 16S rRNA in the small subunit
Sensitivity to antibiotics like streptomycin
Presence of 28S rRNA
Sedimentation coefficient of 70S
Polytene chromosomes, found in certain insect tissues, exhibit distinct banding patterns. These bands represent:
Individual genes arranged linearly along the chromosome.
Regions of heterochromatin exclusively.
Regions where DNA replication has been halted prematurely.
Regions of highly condensed chromatin corresponding to inactive genes interspersed with less condensed regions of active genes.
