An infectious agent causing leaf mottling was isolated and passed through a bacterial-retaining filter. Biochemical analysis confirmed that the particle contains single-stranded RNA enclosed by capsomeres, but completely lacks cytoplasm, membrane-bound organelles, and metabolic enzymes. Which of the following statements accurately describes the biological nature of this entity?
- It is an acellular obligate intracellular parasite possessing only one type of nucleic acid enclosed in a protein coat.Cevap
- BIt is a specialized prokaryotic cell possessing cytoplasm and containing both DNA and RNA.
- CIt is a unicellular organism capable of independent metabolic synthesis and binary fission outside host cells.
- DIt is a microscopic saprophyte possessing a peptidoglycan cell wall and independent ATP-generating machinery.
Cevap
The entity is an acellular obligate intracellular parasite consisting of a single type of nucleic acid enclosed in a protein capsid.
Viruses are non-cellular (acellular) biological entities composed of genetic material (either DNA or RNA) enclosed by a protective protein coat known as a capsid. Outside living host cells, they possess no metabolic activity and act strictly as obligate intracellular parasites.
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Viruses are acellular entities composed of either DNA or RNA enclosed within a protein coat (capsid) and act as obligate intracellular parasites.