Prepare for NEET Biology Diversity in Living World with MCQs & PYQs on NEET.GUIDE. Access free practice, previous year questions, and expert notes to master classification and taxonomy.
A scientist discovers a novel entity exhibiting complex organic molecules, compartmentalization, and energy transformation. However, it lacks a definitive cellular structure and doesn't demonstrate heritability. Which characteristic of life is MOST definitively absent in this entity?
Metabolism
Reproduction and growth
Adaptation
Response to stimuli
Consider a theoretical organism that utilizes silicon as its primary structural element instead of carbon. Assuming all other characteristics of life are present, which fundamental biological process would be MOST significantly challenged by this substitution?
Cellular respiration
Formation of complex, stable biomolecules
Active transport across membranes
Photosynthesis
Prions, infectious protein particles, can induce conformational changes in normal proteins, leading to diseases like Creutzfeldt-Jakob disease. While exhibiting self-propagation, prions lack genetic material. Do prions challenge the conventional definition of living organisms, and why?
No, because they are composed of organic molecules.
Yes, because they lack heritable genetic material yet exhibit a form of 'reproduction'.
No, because they interact with living organisms.
Yes, because they cause disease.
A researcher observes an isolated system containing complex organic molecules undergoing spontaneous self-assembly into membrane-bound structures. These structures exhibit rudimentary metabolism but no reproduction or heritability. Which characteristic of life is the MOST significant barrier preventing these structures from being classified as living organisms?
Metabolism
Cellular organization
Reproduction and growth
Adaptation
Viruses exhibit characteristics of both living and non-living entities. Which of the following properties of viruses MOST strongly supports the argument AGAINST their classification as living organisms?
Presence of genetic material (DNA or RNA)
Ability to evolve and adapt to their environment
Inability to reproduce independently outside a host cell
Specific interaction with host cells
Imagine a synthetic life form created in a lab that uses a novel information storage molecule distinct from DNA or RNA, but still exhibits heritability and undergoes evolution. Which of the following aspects of the current definition of life would MOST require reconsideration in light of this discovery?
The requirement for cellular structure
The dependence on carbon-based chemistry
The specific molecular basis of heredity
The ability to respond to environmental stimuli
A taxonomist is studying a newly discovered organism. They find it to be eukaryotic, multicellular, heterotrophic, with chitinous cell walls and exhibiting absorptive nutrition. Based solely on these characteristics, to which of the following taxonomic groups could the organism most precisely be assigned?
Kingdom Fungi
Phylum Basidiomycota
Domain Eukarya
Class Ascomycetes
While classifying organisms, which of the following presents the biggest challenge to a strictly phylogenetic system of classification?
Convergent evolution
Horizontal gene transfer
Fossil record incompleteness
Morphological similarities in unrelated species
Consider the hierarchical categories: Family, Order, Genus, and Species. Which represents the most inclusive category followed by the most exclusive in the correct order?
Genus, Family
Family, Species
Order, Species
Species, Order
Which statement correctly explains the relationship between taxonomic categories and phylogenetic classification?
Taxonomic categories are arbitrary and have no relationship to phylogeny.
Taxonomic categories always perfectly match the branching patterns of phylogenetic trees.
Taxonomic categories ideally reflect evolutionary relationships revealed through phylogenetic analysis.
Phylogenetic analysis is used to create taxonomic categories, but they don't necessarily reflect evolutionary relationships.
