Microbio Week 9 - Nature of Human Viruses (Exam 3)

Question 1

Viruses are ____________ agents

Answer 1

filterable

Question 2

Are viruses alive?

Answer 2

NO

Question 3

Can viruses replicate in broth?

Answer 3

NO

Question 4

Do viruses divide by binary fission?

Answer 4

NO

Question 5

What do viruses do after they infect a susceptible cell?

Answer 5

Take over cellular machinery
Make cell into a virus-making factory

Question 6

What do viruses require to replicate?

Answer 6

Living cells

Question 7

Do antibiotics and antifungals work on viruses?

Answer 7

NO

Question 8

How do viruses initiate a new infection?

Answer 8

They disassemble in the newly infected cell

Question 9

What do viruses use to complete their life cycle?

Answer 9

Host cell machinery

Question 10

What is the genetic material of viruses?

Answer 10

RNA or DNA

Question 11

New virus particles are made from newly made _________ ___________ in the host cell

Answer 11

viral proteins

Question 12

Infectious virus particle

Answer 12

Virion

Question 13

What are the 2 types of capsids?

Answer 13

Helical
Icosahedral

Question 14

Which capsid varies in length depending on the size of the viral RNA?

Answer 14

Helical

Question 15

All (-)RNA viruses contain which capsid?

Answer 15

Helical

Question 16

All enveloped viruses contain which capsid?

Answer 16

Helical

Question 17

Helical capsids containing human viruses have what?

Answer 17

Lipid envelope

Question 18

T/F: Most helical capsids have a rigid stucture

Answer 18

FALSE, most do NOT have a rigid structure, they are spaghetti-like

Question 19

Viruses with icosahedral capsids can be ___________ or ___________

Answer 19

enveloped; naked

Question 20

What are icosahedral capsids formed from?

Answer 20

Viral capsid proteins

Question 21

What is inside the icosahedral capsid?

Answer 21

Nucleic acid of the virus

Question 22

The structure of icosahedral capsids need to be strong enough to withstand ___________ ________ but still be able to open up once the virus has infected a new cell

Answer 22

stomach acid

Question 23

What is needed to form the icosahedral capsid?

Answer 23

Viral capsid protein

Question 24

What happens once a sufficient amount of viral capsid protein is present?

Answer 24

Icosahedron spontaneously forms

Question 25

The property of icosahedral capsid self-assembly is used to make what?

Answer 25

Virus-like particles in HPV vaccine

Question 26

What does a "naked" virus mean?

Answer 26

No envelope lipid bilayer

Question 27

What are viral envelopes derived from?

Answer 27

Infected cell membranes

Question 28

The viral envelope ____________ are incorporated into the lipid bilayer.

Answer 28

glycoproteins

Question 29

What are the viral envelope glycoproteins that are incorporated into the lipid bilayer required for?

Answer 29

Entry into a cell

Question 30

T/F: If you disrupt the lipid bilayer, the virus cannot enter cells

Answer 30

True!

Question 31

T/F: If a virus is enveloped, it is, on the whole, more fragile and cannot withstand agents that disrupt the envelope, such as stomach acid, detergents, solvents, heat, and drying agents

Answer 31

True

Question 32

Which viruses are more resistant to agents such as stomach acid, detergents, solvents, heat, and drying - enveloped or naked?

Answer 32

Naked viruses

Question 33

Some (naked/enveloped) viruses can withstand stomach acid and are transferred through the oral-fecal route

Answer 33

Naked viruses

Question 34

Name 4 ways naked viruses can be transmitted

Answer 34

Respiratory Sex Congenitally Oral-fecal

Question 35

Name 3 ways enveloped viruses can be transmitted

Answer 35

Respiratory Sex Blood

Question 36

Can enveloped viruses be spread via oral-fecal route?

Answer 36

NO

Question 37

T/F: If an enveloped virus is on a surface in a liquid, like blood or mucus, it can retain some infectivity. However, once the liquid dries, the virus loses infectivity

Answer 37

True

Question 38

What prevents a virus from infecting a cell?

Answer 38

Neutralizing ABs

Question 39

What do neutralizing ABs recognize?

Answer 39

Surface proteins on the virion

Question 40

What do neutralizing ABs for naked viruses bind?

Answer 40

Capsid proteins

Question 41

What do neutralizing ABs for enveloped viruses bind?

Answer 41

Envelope glycoproteins in the lipid bilayer

Question 42

What is the name of the genome for single-stranded RNA viruses?

Answer 42

+ssRNA

Question 43

What genome is the same as messenger RNA (mRNA)?

Answer 43

+ssRNA

Question 44

What is the name of the genome for negative-sense RNA viruses?

Answer 44

-ssRNA

Question 45

What do negative-sense RNA viruses use as a template to make mRNA?

Answer 45

-ssRNA

Question 46

What does BOAR stand for?

Answer 46

Bunyavirus, Orthomyxovirus, Arenavirus, Reovirus

Question 47

What type of genome do BOAR viruses have?

Answer 47

Segmented

Question 48

Linear ssDNA members

Answer 48

Parvovirus

Question 49

Linear dsDNA members

Answer 49

Adenovirus, Herpesvirus, and Poxvirus

Question 50

Closed-circular dsDNA members

Answer 50

Papillomavirus and Polyomavirus

Question 51

Circular, most of the circle is double-stranded, but a small part is single-stranded (circular ds/ssDNA) member

Answer 51

Hepadnavirus

Question 52

+ssRNA members

Answer 52

Hepevirus, Picornavirus, Calicivirus, Togavirus, Coronavirus, Flavivirus, and Retrovirus

Question 53

-ssRNA members

Answer 53

Filovirus, Paramyxovirus, and Rhabdovirus

Question 54

segmented -ssRNA members

Answer 54

Arenavirus, Bunyavirus, and Orthomyxovirus

Question 55

Segmented dsRNA member

Answer 55

Reovirus

Question 56

Circular -ssRNA member

Answer 56

Deltavirus-This is the Hepatitis D virus (HDV) (It is not replication-competent and needs the help of the Hepatitis B Virus to replicate)

Question 57

In this infection, the virus does not kill the cell but does produce virus

Answer 57

Steady state

Question 58

This infection is productive. The virus is made and is non-cytocidal; the virus does not kill the cell

Answer 58

Steady state

Question 59

The virus kills the cell as part of its life cycle; cell death is needed to release the virus.

Answer 59

Lytic/cytocidal

Question 60

The virus kills the cell but not as part of its normal replication. It just makes the cell so sick that it cannot live

Answer 60

Cytopathic/cytocidal

Question 61

This infection is productive and cytocidal. It also produces virus and kills the cell

Answer 61

Lytic/cytocidal Cytopathic/cytocidal

Question 62

The virus infects cells and does not produce any virus but can reactivate

Answer 62

Latent

Question 63

This is non-productive (no virus made) and non-cytocidal (the cell is not killed)

Answer 63

Latent

Question 64

The ability to become latent is an important feature of which virus?

Answer 64

Herpesviruses

Question 65

The infected cell can fuse membranes of neighboring uninfected cells to form a large multinucleated cell

Answer 65

Syncytia forming

Question 66

If a virus can transform a cell, it makes the virus more likely to cause cancer.

Answer 66

Cell-transforming

Question 67

Transforming a cell makes them immortal and able to grow on top of each other (no contact inhibition like most cells)

Answer 67

Cell-transforming

Question 68

Name the 6 viruses that cause cancer

Answer 68

EBV HPV HHV8 HTLV HBV HCV

Question 69

What cancers does EBV cause?

Answer 69

Burkitt lymphoma Nasopharyngeal carcinoma Oral hairy leukoplakia

Question 70

What cancers does HPV cause?

Answer 70

Cervical Anal Oropharynx

Question 71

What cancer does HHV8 cause?

Answer 71

Kaposi's sarcoma

Question 72

What cancer does HTLV cause?

Answer 72

Adult T cell leukemia and lymphoma

Question 73

What cancer does HBV and HCV cause?

Answer 73

Hepatocellular carcinoma

Question 74

All DNA viruses are ____________

Answer 74

icosahedral

Question 75

For the RNA viruses, only the –ssRNA viruses are ________

Answer 75

helical (except for coronavirus)

Question 76

for the RNA viruses, only the –ssRNA viruses are helical, except for which one?

Answer 76

Coronavirus