Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Cells and Macromolecules > Introduction to virology > Flashcards

Introduction to virology Flashcards

1
Q

What structures are featured in simple viruses (5)

A

Envelope coat with glycoproteins

Envelop

Capsomeres

Viral nucleic acid genome

Matrix

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

What structures are features in complex viruses (6)

A

Nucleic acid genome

Capsid

Tail sheath

Plate

Pins

Tail fibres

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

What is the process of virus reproduction (7)

A

Attachment
Entry
Transcription
Translation
Genome replication
Assembly
Exit

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

What happens during viral attachment (2)

A
  1. Spikes, knobs or glycoproteins bind to cell surface receptors
  2. Hydrogen bonds, ionic attractions & van der Waals draw virus closer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What happens during viral entry (2)

A
  1. endocytosis - the cell membrane bends and the virus is engulfed inside.
  2. membrane is formed around the virus within the cell.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What happens during viral transcription (3)

A
  1. ds DNA & ss RNA transcribed by host enzymes
  2. ds RNA, ss (+) RNA & ss (-) RNA = viral enzymes
  3. ss (+) RNA (retroviruses) = viral then host enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What happens during viral translation (2)

A
  1. performed by host enzymes
  2. more than one open frame saves space on viral genome & more than one protein can be synthesised by shifting the codon triplets by one
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens during viral genome replication (2)

A
  1. cytoplasm = RNA.
  2. nucleus = DNA.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What happens during viral assembly (2)

A
  1. Simple virions self-assemble
  2. larger virions use scaffolding proteins.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What happens during viral exit (4)

A
  1. enveloped viruses modify the host membrane taking some when exiting
  2. some form their own membrane
  3. others break the membrane
  4. some viral enzymes weaken the membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are phages (3)

A
  1. virus which only infects bacteria.
  2. Most commonly found in the gut with the gut bacteria.
  3. It can be grown on an agar plate containing bacteria.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are tailed phages (2)

A
  1. A phage where the capsid is icosahedral and the tail is helical.
  2. They force their way into the host by injecting nucleic acid through the cell wall.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the main uses of viruses (5)

A
  1. Phage typing of bacteria (e.g. Salmonella spp.)
  2. Sources of enzymes
  3. Pest control
  4. Antibacterials - phage therapy to lyse bacteria.
  5. Gene therapy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are prions (2)

A

Prions are infectious proteins which induce the conversion of alpha-helix in PrPc (A) [a copper transport protein] to beta-sheets of PrPc (B).

Prions form vacuoles and hardened plaques of prion protein in the brain leading to brain damage.

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

How are prions decontaminated (4)

A

Incineration if possible

Immerse in sodium hydroxide and autoclave at 121℃ for 30 mins; clean and autoclave again.

Autoclave at 134℃ for 18 mins

Flood surfaces with 2N NaOH or undiluted sodium hypochlorite; let stand for 1hr; mop up and rinse with water.

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

How does the Lytic cycle work (4)

A
  1. Phage attaches to the host cell and injects DNA
  2. Phage DNA circulates and enters the lytic cycle
  3. New phage DNA and proteins are synthesised and assembled into virions
  4. Cell lyses, releasing phage virions
17
Q

How does the Lysogenic cycle work (5)

A
  1. Phage attaches to the host cell and injects DNA
  2. Phage DNA circulates and enters the Lysogenic cycle
  3. Phage DNA integrates within the bacterial chromosome by recombination becoming a prophage
  4. Lysogenic bacterium reproduces normally
  5. Occasionally the prophage leaves the bacterial chromosome by another recombination event initiating a lytic cycle.
18
Q

what are examples of viral diseases (7)

A

common cold
ebola
HIV
rabies
SARS
influenza
COVID-19

19
Q

what are viral routes of transmission (5)

A

respiratory
faecal-oral
sexual
skin-breach
vector-borne

20
Q

Wha are the characteristics of viruses (3)

A
  1. parasites, not cell - no organelles
  2. small genome
  3. inert outside host
21
Q

why are the evolutionary origins of viruses unknown (3)

A
  1. only function in host
  2. mutate quickly
  3. no ribosomes to study
22
Q

what are the 4 most common virus shapes

A

icosahedral
helical
enveloped icosahedral
enveloped helical

23
Q

how are viral genomes named (5)

A
  1. only have DNA or RNA - never both
  2. ds (double-stranded) linear
  3. ds circular
  4. ss (single-stranded) linear
  5. ss circular

Cells and Macromolecules (27 decks)

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