Unit 1: 6.1

Question 1

General characteristics of viruses/virions as pathogens?

Answer 1

• infectious acellular pathogens
• obligate intracelular, specific
• DNA or RNA genome never both
• genome has capsid or phospholipid membrane w/ glycoproteins
• lack genes for reproduction

Question 2

Can viruses infect every cell?

Answer 2

• can infect host cells of plants, animals, fungi, protists, bacteria, and archaea
• only infect specific hosts and specific cells in hosts

Question 3

Bacteriophage

Answer 3

The viruses that can infect bacteria

Question 4

Mechanical vector

Answer 4

When an animal carries a viral pathogen on outside of body and gives it to host through physical contact

Question 5

Biological vector

Answer 5

Animal carries viral pathogen inside its body and transmits to host through biting

Question 6

How big are viruses?

Answer 6

Range from 20nm to 900 nm

-cannot be observed with regular light microscope

Question 7

Naked viruses or nonenveloped viruses

Answer 7

Viruses formed only from nuclei acid and capsid

Question 8

Enveloped viruses

Answer 8

Viruses formed with a nucleic acid packed capsid with a lipid bilayer

Question 9

Viral envelope

Answer 9

A small part of phospholipid bilateral when viron buds from a host cell

Question 10

What are spikes?

Answer 10

Protein structures that allow viruses to attach and enter a cell

Question 11

What are influenza viruses identified by?

Answer 11

Their H and N spikes

Question 12

What shapes can viruses be?

Answer 12

• helical
• polyhedral
• complex

Question 13

Viral family names end in?

Answer 13

viridae

Question 14

Virus genus ends in?

Answer 14

virus

Question 15

Genome of virus?

Answer 15

• DNA or RNA never both
• single stranded (ss)
• double stranded (ds)
• linear
• circular

Question 16

Viral life cycle

Answer 16

1. Infect a host in their host range
2. Genome enters a host cell and makes virions
3. New virions are made in host cell by assembly of viral components
4. New virions transport the viral genome to another host cell to carry out another round of infection

Question 17

Provirus vs prophage

Answer 17

Provirus integrates in eukaryotic cells while prophage integrates in bacteria cells

Question 18

What type of virus must cart its own RNA polymerase?

Answer 18

-ssRNA