Brainscape's Knowledge GenomeTM

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


See full index

Microbiology > Chapter 13 Viruses > Flashcards

Chapter 13 Viruses Flashcards

1
Q

what are the four general characteristics of viruses?

A
  1. contain single TYPE of either DNA or RNA
  2. contain protein coat
  3. multiply only inside living cells
  4. contain specialized structures that transfer viral nucleic acid to other cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

is the general consensus that viruses are living or non-living? why?

A

non-living
because they can only survive within a host cell

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

what is the suffix that denotes genus names of viruses?

A

-virus
(ie: Coronavirus)

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

what is the suffix that denotes family names in viruses?

A

-viridae
(ie: Papilloviridae)

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

what is the suffix that denotes order names of viruses?

A

-ales

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

what do we put in front of genus names to classify them?

A

host name
(ie: Human Papillomavirus)

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

what is the basic structural definition of a virus?

A

obligatory intracellular parasites (tiny infectious particle)

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

what is the size range of viruses?

A

20 nm to 1000nm in length

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

are viruses smaller or larger than human RBCs?

A

significantly smaller

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

what is a virion?

A

complete, fully developed viral particle

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

describe the appearance of what the nucleic acid of a virion could look like?

A

DNA or RNA
single or double stranded
linear or circular

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

list the basic components of a virus

A

nucleic acid
capsid
envelopes
spikes

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

describe the capsid

A

protein coat
contain capsomeres (protein subunits)

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

describe the envelopes of some viruses?

A

extra protective layer
roughly spherical
forms using host cells membrane
made up of lipids/proteins/carbohydrates

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

what is a viral spike composed of?

A

carbohydrate-protein projections

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

what is the role of viral spikes?

A

help attach to host cell
is used as a means of identification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what protects viruses in nonenveloped viruses?

A

just the capsid

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

what is the source of the viral envelope?

A

host cell’s membrane

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

what are the two possible viral life cycles

A

lytic cycle
lysogenic cycle

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

in viral multiplication, what do smallest nonenveloped virions use to replicate their DNA/RNA?

A

everything from the host cell for replication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

in viral multiplication, what do larger virions use?

A

few of their own enzymes or mRNA plus the host cells enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are the 5 basic steps for virus lytic cycle?

A
  1. attachment
  2. entry
  3. replication and gene expression (biosynthesis)
  4. assembly of parts (maturation)
  5. release
23
Q

what does the lytic cycle in simple terms cause to happen to host cell?

A

lysis or cell death of host

24
Q

what does the lysogenic cycle (in simple terms) cause to happen to host cell?

A

host cell to remain active (for period of time)

25
describe the penetration phase of the lytic cycle?
bacteriophage release "phage lysozyme" in order to destroy bacterial cell wall for it to inject its DNA into the cell
26
describe the biosynthesis stage of the lytic cycle
virus degrade bacteria’s chromosome and break it down in order to rearrange it to make its own DNA with the use of bacteria’s enzymes and ribosomes
27
what is the eclipse period of the lytic cycle?
occurs in the biosynthesis stage is when virions are not yet present within the cell
28
describe the maturation stage of the lytic cycle
viral components are assembled into virions
29
describe the release stage of the lytic cycle
lysozyme breaks down cell wall virions are released plasma membrane lyses
30
what components of the host cell are required by the virus to complete the viral life cycle?
nucleotides enzymes ribosomes
31
after which step can lysogenic cycle or lytic cycle occur?
after injection of viral DNA
32
in lysogenic cycle, what happens after the viral DNA is injected?
Phage DNA integrates with bacterial chromosome by recombination to produce a prophage
33
what is the benefit of a bacterial prophage?
can give new traits to bacteria
34
what occurs after the prophage is developed within the lysogenic cycle?
bacteria reproduce normally and new prophage-containing bacteria form
35
what can occasionally occur during the lysogenic cycle that results in its ensured end?
prophage may spontaneously excise (pop out) of bacterial chromosome this then starts the biosynthesis step of lytic cycle
36
what is a provirus vs a prophage
prophage is bacteriophage DNA within bacterial chromosome provirus is animal virus DNA within animal chromosome
37
which can excise from host's DNA? provirus or prophage
prophage
38
can provirus genes be used by the host cell? can prophage?
Either can be used by the cell
39
when does a prophage become active again?
Spontaneous event the action of UV light, or chemicals can lead to excision of phage DNA
40
can a cell infected with a provirus be attacked by virions of the same type?
No it cannot
41
What is special about Retroviruses? What is the name of the important enzyme?
They use a special enzyme called reverse transcriptase to translate its genetic information into DNA.
42
what can happen to the provirus of an infected cell?
it can replicate on its own within the host cell's genome
43
what is a prion?
proteinaceous infectious particles misfolded proteins
44
what is the mechanism for prion-based diseases?
45
what are the general characteristics for prion-based disease?
brain damage causing: tremors loss of cognitive ability loss of balance and co-ordination slurred speech abnormal jerking movements.
46
what does the abbreviation of CJD stand for?
Creutzfeldt-Jakob disease
47
what is a viroid composed of?
short pieces of naked RNA no protein coat
48
what do viroids infect?
plants
49
describe why viruses are considered not complete independent cells?
viruses need a host cell to replicate they do not make any/enough of their own enzymes/nucleotides/ribosomes to replicate on their own
50
name two differences between animal viruses and bacteriophages
animal viruses infect animal cells while bacteriophages infect bacterial cells animal viruses (specifically retroviruses) can form a permanent provirus within the animal's chromosome. while bacteriophages form prophages within bacterial chromosomes that can be excised spontaneously
51
how are the two life cycles of bacteriophages different?
lytic cycle: sole purpose is to produce more virions/ immediately kill host lysogenic cycle: purpose is to integrate its DNA to bacterial chromosome, giving new traits to bacteria/ does not kill host immediately
52
what is an advantage of using bacteriophages as a form of therapy (phage therapy)?
bacteriophages only infect specific bacteria, so it won't harm human cells or own microbiome
53
what is something interesting you learned in class?
not to rely to heavily on hand sanitizer because hand sanitizer can cause super bugs and that hand washing is always the best option

Microbiology (23 decks)

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