Viruses!

Question 1

What is a virus

Answer 1

A virus is an acellular organism which relys on the cellular machinary of a host cell to survive

Question 2

What are the main 2 components of viruses
+ bonus sometimes

Answer 2

nuclear material
capsid

sometime:
envelope
spike glycoproteins`

Question 3

describe the viral genome

Answer 3

3 types:
straight chain
circular
segmented - can cause rapid gene transfers between virus

2 varients:
ss or ds, DNA or RNA

RNA specific:
can be positive sense = no mRNA transcription
can be negative sense = need mRNA transcription

3-1000 genes long, replication proteins + strutureal proteins

Question 4

descirbe the types of virus capsids and symetry

Answer 4

Made from proteins called capsomeres
Symetreys:
- Helical
- icosohedral: 20 faces
- complex : combination of I and H

Question 5

Define a naked and enveloped virus

Answer 5

Enveloped have a covering outside the capsid made from lipopolysacharides
- envelope from PM of host cell

naked = no envelope just capsid

Question 6

What is a spike protein
+ example of a virus with them

Answer 6

A binding site for receptors on host cells
made from glycoproteins-
sars-cov-2 had them which bound to ACE2 receptor
Target for vaccines, covering them to prvenet virus attachemnt

Question 7

What are the three types of viruses replication styles covered

Answer 7

Bacteriophages - Lytic cycle
Sars-cov-2 replication
retrovirus

Question 8

What is the lytic cycle

Answer 8

6 steps
Attachment
penitration
unsheething
gene exspression and replication
assemblance
lysis

Question 9

What is the cycle for virus replication in human cells (e.g. sar-cov-2)

Answer 9

Attachement
fussion into the cell
Genome translation of replication proteins
Viral RNA synthesis
assemblance of virions
exocytosis- using the golgi machinary

Question 10

What is the process of a retrovirus infection such as HIV

Answer 10

HIV - contains RNA, reverse transcriptase, viral integrase

1. attachement penitration unsheething
2. RNA-> DNA via reverse transcritase changing RNA into double stranded DNA
3. viral intergrase intergrates the DNA into the host cell genome
4. exspression of genes - new virus parts formed + glycoproteins made in the golgi sent to the PM
5. assemblance
6. exocytosis VIA pm which is has bound glycoproteins

Question 11

What are virus replactions called

Answer 11

Virions