structural features common to viruses Flashcards
What are viruses and how do they reproduce?
Viruses are non-cellular agents that infect cells and reproduce inside them by hijacking the host’s cellular machinery.
What is the size range of most viruses?
Most viruses range from 20-300 nm in diameter, making them smaller than nearly all bacteria and much smaller than eukaryotic cells.
Why must viruses be small in size?
Viruses must be small because they lack cytoplasm and other cellular features, and need to be small enough to enter host cells to replicate.
Do viruses grow in size?
No, viruses do not grow. They have a fixed size and reach full size as soon as they are assembled inside the host cell.
What type of genetic material do viruses contain?
Viruses contain either DNA or RNA as their genetic material, which is compatible with the host cell’s protein synthesis machinery.
What is the role of the protein capsid in viruses?
The protein capsid encloses the virus’s genetic material, protecting it and giving the virus a symmetrical structure. The capsid is made of repeating protein subunits.
Do viruses have cytoplasm and enzymes?
No, viruses do not have cytoplasm or the necessary enzymes for metabolism. They rely on the host cell’s machinery for replication and infection processes.
