Viruses are microscopic infectious agents that replicate inside living host cells, going through a life cycle of entry, replication, latency, and destruction. Viroids are infectious RNA pathogens that replicate in host cells and silence gene expression, while prions are protein-based agents that induce misfolding of healthy proteins, leading to host destruction. Together, these agents illustrate different mechanisms of infection and pathogenesis.

1. A virus is a microscopic infectious agent that replicates only inside the living cells of other
organisms. The virus life cycle has four stages and are entry, replication, latency and destruction.
The virus attaches itself to the membrane of the of the host by envelope protein, then initiates
replication using host replication machinery and enters into a latence period. Finally it destroys
the host releasing virion particles.
Viroids are the microscopic infectious pathogens consist of circular, single-stranded RNA. Once
it enters to the host cell it replcates its single stranded RNA with the help of the host polymerase
and silence the gene expression of the host.
A prion is an infectious agent made entirely of protein material. Prion enters a healthy organism,
it helps existing, properly folded proteins to convert into the misfolded prion protein,thus leading
to destruction of the host.
Solution
A virus is a microscopic infectious agent that replicates only inside the living cells of other
organisms. The virus life cycle has four stages and are entry, replication, latency and destruction.
The virus attaches itself to the membrane of the of the host by envelope protein, then initiates
replication using host replication machinery and enters into a latence period. Finally it destroys
the host releasing virion particles.
Viroids are the microscopic infectious pathogens consist of circular, single-stranded RNA. Once
it enters to the host cell it replcates its single stranded RNA with the help of the host polymerase
and silence the gene expression of the host.
A prion is an infectious agent made entirely of protein material. Prion enters a healthy organism,
it helps existing, properly folded proteins to convert into the misfolded prion protein,thus leading
to destruction of the host.