Practice Questions

Viruses can infect only cells possessing compatible receptors that allow attachment and entry. This determines host specificity and tissue tropism.

The icosahedral design provides great structural strength while requiring relatively few capsid proteins.

Ebola virus has a long, filamentous appearance and belongs to the Filoviridae family.

Mumps virus belongs to the Paramyxoviridae family and possesses a negative-sense single-stranded RNA genome.

Measles virus belongs to the Paramyxoviridae family and causes a highly contagious viral disease characterized by fever and rash.

Enveloped viruses commonly enter cells by membrane fusion or receptor-mediated endocytosis.

HIV infects human immune cells and therefore belongs to the animal viruses.

Complex viruses, such as bacteriophage T4, possess an icosahedral head, helical tail, and specialized attachment structures.

Hepatitis C virus belongs to the Flaviviridae family and contains a positive-sense ssRNA genome.

Retroviruses possess single-stranded RNA and use reverse transcriptase to synthesize DNA before replication. HIV is the best-known example.