6.2.2 - Viruses as pathogens Flashcards
What are viruses without an envelope referred to as?
Naked virus
What are bacteriophages?
Viruses that target bacterial cells.
Why are viruses specific to certain cells?
Due to the presence of antigen markers
How is influenza spread?
Droplets from coughs and sneezes
Direct contact with an infected person
Contact with contaminated surfaces
How do bacteriophages enter a host cell?
They inject their genetic material inside the host cell
What is enedocytosis when it’s related to a virus entering a host cell?
The lipid envelope of a virus fuses with the cell membrane of host cells
What cells does influenza target?
Ciliated epithelial cells in the respiratory tract
Why can enveloped viruses enter host cells by endocytosis?
Their lipid envelope fuses with the membrane of the host cell
What are the glycoproteins that form the antigens of the flu virus?
Hemagglutinin (H)
Neuraminidase (N)
Describe the mode of infection of influenza.
The virus inserts its RNA into the cell. The host cell machinery is then used to produce new viral proteins and eventually new virus particles.
Which virus has both a polyhedral capsid and an envelope?
HIV
Explain why viruses are dependent on living cells.
They are unable to reproduce independently.
Because they don’t have appropriate enzymes.
Explain how the influenza virus has a pathogenic effect.
The virus targets ciliated epithelial cells in respiratory tract.
Virus has glycoproteins on surface.
Virus replicates via the lyctic cycle.
Leading to cell lysis.
