Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Microbiology Exam 3 > Viruses Part II > Flashcards

Viruses Part II Flashcards

Chapter 13 (57 cards)

Start Studying
1
Q

What are the 3 types of viruses? (host cell type)

A
  • Bacteriophage
  • Plant Viruses
  • Animal Viruses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are primary cell lines?

A

Derived from tissues by enzymes (die after a couple of generations)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are diploid cell lines?

A

Derived from human embryos (50-100 generations and then die)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do viral genes code for? (3)

A
  • capsid
  • structural proteins
  • enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the virus use host cell enzymes for? (3)

A
  • protein synthesis
  • energy production
  • ribosomes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where do viruses replicate in?

A

ONLY inside a cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What do viruses control when they invade a cell? (2)

A
  • metabolic machinery
  • replicative machinery
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the lytic cycle and give an example:

A
  • host cell is lysed after viral replication
  • T4 bacteriophage, Influenza Virus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the lysogenic/latent cycle and give an example:

A
  • host cell stays alive after replication
  • viral genome integrated into host’s genome
  • lambda bacteriophage, retroviruses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the steps of the viral replication cycle in animal viruses? (6)

A
  • attachment/absorption
  • penetration/entry
  • uncoating
  • biosynthesis
  • maturation/assembly
  • release
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do viral particles attach to a host cell?

A

Via specific receptors on the host cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the attachment sites of viral particles made of?

A

Spikes or fibers that bind to receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the attachment sites for naked viruses

A

nucleocapsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the attachment sites for enveloped viruses

A

envelope on spikes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do naked viruses enter the host cell? (1)

A
  • via receptor mediated endocytosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do enveloped viruses enter the host cell (2)?

A
  • via receptor mediated endocytosis
  • via fusion of envelope with host cell plasma membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is uncoating?

A

Separation of nucleic acid from the protein capsid coat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What causes uncoating? (2)

A
  • host lysosomal enzymes
  • configurational changes in the capsid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Describe synthesis in viral replication

A

Virus takes over host’s biosynthetic “machinery”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is produced in synthesis? (3)

A
  • new viral nucleic acid molecules
  • capsid proteins
  • other viral components
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Where do DNA viruses replicate?

A
  • In the nucleus (except Poxviruses)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What enzyme do DNA viruses use?

A
  • DNA dependent DNA polymerase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where do RNA viruses replicate?

Study These Flashcards
A
  • In the cytoplasm (except Retroviruses and Orthomyxoviruses)
24
Q

What enzyme do RNA viruses use?

Study These Flashcards
A
  • RNA dependent RNA polymerase
25
What happens in maturation/assembly? (2)
- capsomers assembled into capsids - newly synthesized viral DNA inserted into capsids (forms new virions)
26
What happens in release for naked viruses? (2)
- released from host cell by lysing the cell - host cell dies
27
What happens in release for enveloped viruses? (2)
- bud out of host cell - acquire envelope from the host cell's plasma membrane
28
How do retroviruses replicate? (3)
- through DNA intermediate - double stranded DNA copy of the virus RNA made - integrates into host genome
29
What enzyme is used in replication of retroviruses?
Reverse transcriptase
30
What is the simplified version of how retroviruses replicate?
RNA -> DNA -> integrates
31
List the steps of biosynthesis in retroviruses (4)
- RNA -> double stranded DNA - DNA enters nucleus -> integrates - DNA remains in host's genome, PROVIRUS - integrated DNA -> RNA -> proteins
32
How do retroviruses leave the host cell?
via budding
33
What is viral latency?
Time period where there is no replication of the viral genome
34
(T/F) Viruses cause disease during latency
False, they only cause disease when activated by different stimuli
35
Name two examples of viruses that remain latent until activation:
- HSV-1, Simplexvirus - Chicken pox virus, Varicellovirus
36
Where is HSV-1 latent in?
Nerve cells
37
What does Varicellovirus cause after activation?
(Chicken pox) Shingles
38
What viruses cause cancer in humans? (2)
Human T-cell Lymphotropic Virus - HTLV-1 - HTLV-2
39
What viruses cause leukemia?
Both retroviruses
40
What do both retroviruses cause?
Leukemia
41
What viruses cause cancer in animals? (3)
- Epstein-Barr Virus (EBV) - Hepatitis B Virus (HBV) - Human Papilloma Virus (HPV)
42
What is EBV associated with? (2)
- African Burkitt's Lymphoma - Nasopharyngeal carcinoma
43
What is HBV associated with? (1)
hepatocellular carcinoma (liver cancer)
44
What is HPV associated with? (1)
Cervical carcinoma
45
What are oncogenes?
Tumor genes
46
What is an oncogenic virus?
Virus that promotes tumor formation
47
Where are oncogenes derived from?
Normal cellular genes
48
Where do oncogenic viruses integrate in?
Host's chromosome
49
What are prions?
Proteinaceous Infectious Particles: affect cellular proteins
50
What diseases are caused by prions? (4)
- Kuru - Creuztfeld-Jacob Disease - Mad Cow Disease (bovine spongiform encephalopathy) - Scrapie (found in sheep)
51
What are common factors in diseases caused by prions? (2)
- all are neurological diseases (spongy appearance of the brain) - all are fatal
52
What do prions do?
Convert normal proteins to an infectious abnormal protein
53
What is PrPc?
A normal cellular protein
54
What is PrPsc?
A scrapie protein, accumulates in brain cells + forms plaques
55
What are viroids?
Short pieces of naked RNA (no protein coat)
56
What do viroids cause?
Some plant diseases
57
What do viruses do?
Stops RNA from coding proteins

Microbiology Exam 3 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions