Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Block 9 Ellen > Viral properties L9 > Flashcards

Viral properties L9 Flashcards

1
Q

3 shape variations of viruses

A

Icosahedral
filamentous
spherical

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

icosahedral=

A

highly symmetric 20 faces

self-assembles

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

3 significant features of viruses

A
  1. Obligate intracellular parasite
  2. Depend on biochemistry machinery of host cell to replicate
  3. replication is by assembly of individual components
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the nucleocapsid

A

the genome contained within a protein capsule

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

virion=

A

the infective viral particle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

for non-enveloped viruses (naked)=

A

nucleocapsid= virus particle= virion

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

for enveloped viruses =

A

virion= nucleocapsid + envelope

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what often protrudes from the surface of the virus particle and are involved in contact with the host cell

A

protein or glycoprotein structures called spikes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what can the enveloped be made from

A

derived from the host membrane via budding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

e.g of enveloped virus

A

influenza

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

spikes on influenza (2)

A
  • H

- N

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

H spike=

A

hemagglutinin receptor recognition on host cell (specificity

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

N spike=

A

neuramindase

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

what are H and N susceptible to (2)

A
  • antigenic drift (mutations)

- Shift (recombinations)

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

e.g of a naked virus

A

norovirus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

3 advantages of being non-enveloped

A
  1. more stable in face of environmental spread (no phospholipid membrane
  2. spreads more easily
  3. Survives gut, poor water treatment ect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

4 consequences about enveloped viruses

A

must stay wet to remain infectious
very sensitive to detergents
spreads through large droplets
does not need to kill cell to spread (buds)

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

e.g 3 enveloped viruses

A

HIV
Ebola
Influenza

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the key way of classifying viruses

A

Nature of the genome

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

transcription=

A

making a + strand mRNA from DNA

21
Q

what is negative mRNA

A

the complementary strand

22
Q

translation=

A

proteins from mRNA

always needs positive stranded mRNA

23
Q

2 tasks to make new virus particles

A
  1. make mRNA to be translated to make new viral proteins

2. Make nucleic acids; copies of own genome to be packaged

24
Q

3 classes of protein viral genome codes for

A
  1. proteins for progeny viral particles
  2. Enzymes for genome replication
  3. Proteins to interfere with host immune defence
25
Q

do humans have negative RNA

A

no

26
Q

3 classification of viruses on genome

A

RNA
DNA
retrovirus

27
Q

retrovirus=

A

contain reverse transcriptase

have RNA to DNA step in life cycle

28
Q

6 stages of the infectious cycle

A
  • attachment
  • penetration
  • uncoating
  • replication (gene expression)
  • assembly
  • release
29
Q

burst size=

A

yield of infectious virus/cell

time required for single cell of virus to reproduce

30
Q

Negative ss RNA are all ______

A

enveloped

31
Q

entire life cycle is normally extra nuclear (3)

A

Negative ss RNA
Positive ss RNA
positive ds RNA

32
Q

in neg ss RNA how are progeny viruses released

A

budding

33
Q

life cycle of Retrovirus (e.g HIV)

A
  • RT enzyme
  • viral genome integrates into host cell chromosomal DNA
  • viruses are packaged in cytoplasm and released by budding
34
Q

where are DNA viruses usually assembled

A

in the nucleus and released by cell lysis

35
Q

why very few antivirals?

A

limited choice of targets for anti-viral drugs

36
Q

what is it called when viral infection causes death of host cell

A

lytic infection

37
Q

what happens when genomic material is retained in host cells

A

latent infection

38
Q

slow release of viral particles may lead to

A

persistant infection

39
Q

how can viruses cause tumour cells

A

virus might induce transformation of the host cell leading to formation of normal cells to tumour cells

40
Q

what can be viral oncogenes (4)

A

regulatory factors
receptor molecules for growth factors
signalling molecules
transcription factors

41
Q

2 ways oncogenes can occur

A
  1. introduction of oncogenes

2. insertion of viral DNA into host genome activates host cellular oncogenes

42
Q

shape of rotavirus

A

icosahedral

43
Q

shape of ebola

A

filamentous

44
Q

shape of adenovirus

A

spherical

45
Q

name 4 negative SS RNA viruses

A

influenza,
mumps and measles
rabies
ebola

46
Q

name 3 positive SS/ds RNA viruses

A

poliovirus
dengue
hepatitis C

47
Q

name 2 DNA viruses

A

herpes, Epstein barr virus (EBV)

48
Q

name a retrovirus

A

HIV

Block 9 Ellen (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions