Brainscape's Knowledge GenomeTM

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


See full index

NSG 20 > CHAP 13 > Flashcards

CHAP 13 Flashcards

1
Q

What are acellular disease-causing agents that lack cell structure and cannot metabolize, grow, self- reproduce, or respond to their environment.

A

Viruses, viroids, and prions

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

a tiny infectious agent with nucleic acid

A

Virus

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

nucleic acid surrounded by proteinaceous capsomeres that form a coat are called?

A

Capsid

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

It exists in an extracellular state and an intracellular state

A

Virus

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

a complete viral particle, including a nucleic acid and a capsid, outside a cell.

A

Virion

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

They include either DNA or RNA. Viral genomes may be dsDNA, ssDNA, dsRNA, or ssRNA They may exist as linear or circular and singular or multiple molecules of nucleic acid, depending on the type.

A

Genomes of virus

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

are specific for their hosts’ cells because viral attachment molecules are complementary in shape to specific receptor mole- cules on the host’s cells.

A

Virus

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

All types of organisms can be infected by ?

A

Viruses

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

a virus that infects a bacterial cell.

A

bacteriophage

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

can have a membranous envelope or be naked—that is, have no envelope.

A

Virions

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

are classified based on type of nucleic acid, presence of an
envelope, shape, and size.

A

Viruses

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

Who has recognized viral family and genus names. With the exception of three orders, higher taxa are not established.

A

International Committee on Taxonomy of Viruses (ICTV)

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

Viruses depend on random contact with a specific host cell type for replication. Typically, a virus in a cell proceeds with what cycle?

A

lytic replication cycle

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

What are the stages of lytic replication cycle?

A

attachment, entry, synthesis, assembly, and release.

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

With animal viruses, the entire virion often enters the cell, where the capsid is then removed in a process called

A

Uncoating

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

Within the host cell, the viral nucleic acid directs synthesis of more viruses using what?

A

metabolic enzymes and ribosomes of the host cell.

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

Assembly of synthesized virions occurs in?

A

Host cell

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

Virions are released from the host cell either by?

A

lysis of the host cell (seen with phages and animal viruses) or by the extrusion of enveloped virions through the host’s cytoplasmic membrane (budding)

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

a process seen only with certain animal viruses.

A

Budding

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

Temperate phages (lysogenic phages) enter a bacterial cell
and remain inactive in a process called

A

lysogeny or lysogenic replication cycle

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

inactive phages are called what and are inserted into the chromosome of the cell and passed to its daughter cells.

A

prophages

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

results when phages carry genes that alter the phenotype of a bacterium

A

Lysogenic conversion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

At some point in the generations that follow, a prophage may be excised from the chromosome in a process known as

A

induction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

During induction,
the prophage again becomes a

A

lytic virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

dsDNA viruses use their DNA like cellular DNA in transcription and replication except?

A

hepatitis B virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

These viruses have positive-sense single-stranded RNA, which can be directly translated by ribosomes to synthesize protein.

A

ssRNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

From the positive-sense single-stranded RNA (∙ssRNA) what is transcribed to serve as a template for more + ssRNA.

A

complementary negative-sense single-stranded RNA ( - ssRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

carry reverse transcriptase, which transcribes DNA from RNA.

A

Retroviruses (HIV, +ssRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

carry an RNA-dependent RNA transcriptase for transcribing mRNA from the - ssRNA genome, and the mRNA is translated to protein.

A

Negative-sense single-stranded RNA (-ssRNA)

30
Q

these viruses, the positive strand of RNA functions as mRNA, and each strand functions as a template for an RNA complement.

A

dsRNA

31
Q

a process similar to lysogeny, an animal virus remains inactive in a cell, possibly for years, as part of a chro- mosome or in the cytosol.

A

Latency

32
Q

also known as a provirus.

A

Latent virus

33
Q

is uncontrolled cellular reproduction in a multicel- lular animal.

A

Neoplasia

34
Q

A mass of neoplastic cells

A

Tumor

35
Q

A mass of neoplastic cells relatively harmless

A

Benign tumor

36
Q

A mass of neoplastic cells invasive

A

malignant tumor

37
Q

Malignant tumors are also called?

A

Cancer

38
Q

describes the spreading of malignant tumors.

A

Metastasis

39
Q

Environmental factors or oncogenic viruses may cause?

A

Neoplasia

40
Q

In the laboratory, viruses must be cultured inside mature organ- isms, in embryonated chicken eggs, or in cell cultures because?

A

viruses cannot metabolize or replicate alone.

41
Q

When a mixture of bacteria and phages is grown on an agar plate, bacteria infected with phages lyse, producing clear areas called?

A

Plaques on the bacterial lawn.

42
Q

A technique used to estimate phage numbers.

A

Plaque assay

43
Q

Viruses can be grown in two types of ?

A

Cell cultures

44
Q

What culture last about 100 generations,

A

diploid cell cultures

45
Q

What cell culture is derived from cancer cells, last longer.

A

continuous cell cultures

46
Q

Outside cells, viruses do not appear to be alive, but within cells,
they exhibit lifelike qualities, such as the ability to replicate.

True or False

A

True

47
Q

are small circular pieces of RNA with no capsid that infect and cause disease in plants

A

Viroids

48
Q

pathogenic RNA mole- cules have been found in

A

Fungi

49
Q

are infectious protein particles that lack nucleic acids

A

Prions

50
Q

replicate by inducing similar, normal proteins to misfold into new prions—a process called

A

Templating

51
Q

Diseases caused by these are spongiform encephalopathies, which involve fatal neurological degeneration.

A

Prions

52
Q

Which of the following is not an acellular agent?

a. viroid
c. rickettsia
b. virus
d. prion

A

c. rickettsia

53
Q

Which of the following statements is true?
a. Viruses move toward their host cells.
b. Viruses are capable of metabolism.
c. Viruses lack a cytoplasmic membrane.
d. Viruses grow in response to their environmental conditions.

A

c. Viruses lack a cytoplasmic membrane.

54
Q

A virus that is specific for a bacterial host is called a

a. phage
c. virion
b. prion
d. viroid

A

a. phage

55
Q

A naked virus __________________.
a. has no membranous envelope
b. has injected its DNA or RNA into a host cell c. is devoid of capsomeres
d. is one that is unattached to a host cell

A

a. has no membranous envelope

56
Q

Which of the following statements is false?

a. Viruses may have circular DNA.
b. dsRNA is found in bacteria more often than in viruses.
c. Viral DNA may be linear.
d. Typically, viruses have DNA or RNA but not both.

A

b. dsRNA is found in bacteria more often than in viruses.

57
Q

When a eukaryotic cell is infected with an enveloped virus and sheds viruses slowly over time, this infection __________________.
a. is called a lytic infection
b. is a prophage cycle
c. is called a persistent infection
d. is caused by a quiescent virus

A

c. is called a persistent infection

58
Q

Another name for a complete virus is __________________.
a. virion
b. viroid
c. prion
d. capsid

A

a. virion

59
Q

Which of the following viruses can be latent?
a. HIV
b. chicken pox virus
c. herpesviruses
d. all of the above

A

d. all of the above

60
Q

Which of the following is not a criterion for specific family classi- fication of viruses?
a. the type of nucleic acid
b. envelope structure
c. capsid type present
d. lipid composition

A

d. lipid composition

61
Q
  1. A clear zone of phage infection in a bacterial lawn is __________________.
    a. a prophage
    b. a plaque
    c. naked
    d. a zone of inhibition
A

b. a plaque

62
Q

harmless neoplastic cells

A

benign tumor

63
Q

invasive neoplastic cells

A

cancer

64
Q

removal of capsomeres from a virion

A

uncoating

65
Q

inactive virus within bacterial cell.

A

prophage

66
Q

complete viral particle

A

virion

67
Q

a membrane on the outside of a virus.

A

envelope

68
Q

protein coat of virus

A

Capsid

69
Q

transcribes DNA from RNA

A

Retrovirus

70
Q

a virus that infects a bacterium.

A

Bacteriophage

71
Q

dormant virus in a eukaryotic cell.

A

Provirus

NSG 20 (20 decks)

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