In an investigation of plant pathogens, a biological entity is isolated that remains completely inert when placed in a sterile nutrient broth, yet multiplies rapidly when inoculated into living plant tissue. Biochemical analysis confirms that the entity consists exclusively of a single-stranded ribonucleic acid () core surrounded by a protein coat, lacking a cytoplasm, cell membrane, or organelles. What fundamental structural characteristic accounts for its complete inability to replicate in the nutrient broth?
- Absence of metabolic enzymes and ribosomes required for independent protein synthesisCevap
- BPresence of a protective peptidoglycan wall that prevents nutrient uptake outside host cells
- CInactivation of internal cytoplasmic organelles when exposed to non-living broth media
- DSimultaneous possession of both DNA and RNA genomes that inhibit extracellular growth
Cevap
The inability of the virus particle to replicate in a nutrient broth is due to its acellular nature, specifically the absence of metabolic enzymes and ribosomes required for independent protein synthesis.
Viruses are acellular entities that consist of nucleic acid (either or ) enclosed within a protein coat (capsid). Because they lack cytoplasm, ribosomes, and respiratory enzymes, they cannot synthesize proteins or produce energy independently. Consequently, they behave as obligate intracellular parasites that rely on host cell machinery for replication and remain metabolic inert outside living host cells.
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Acellular Structure and Obligate Intracellular Parasitism of Viruses
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