Chapter 7 - Genetic Transfer and Mapping in Bacteria Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Are bacteria usually haploid or diploid?

A

Haploid

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

Bacteria reproduce asexually through this method

A

Binary fission

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

In this process, a segment of bacterial DNA is transferred from one bacterium to another

A

Genetic transfer (or horizontal genetic transfer)

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

These are viruses that infect bacteria

A

Bacteriophages

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

Do bacteriophages contain their own genetic material?

A

Yes

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

Like sexual reproduction in eukaryotes, genetic transfer in bacteria enhances this

A

Genetic diversity

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

What are three ways in which genetic material can transfer from one bacterium to another?

A

Conjugation, transduction, transformation

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

This method of genetic transfer involves direct physical contact between bacteria

A

Conjugation

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

This method of genetic transfer involves bacteriophages

A

Transduction

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

This method of bacterial genetic transfer involves uptake from the environment

A

Transformation

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

In conjugation, this circular segment of DNA is transferred to a recipient cell

A

Plasmid

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

In transformation, is the donor cell alive or dead?

A

Dead

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

Genetic transfer in bacteria was discovered in 1946 by these two scientists

A

Joshua Lederberg and Edward Tatum

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

What are the two different strains of E. coli that Joshua Lederberg and Edward Tatum studied?

A

Auxotrophs and prototrophs

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

This strain of E. coli cannot synthesize a particular nutrient and therefore need it in their growth medium

A

Auxotrophs

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

This strain of E. coli make all their nutrients from components in their growth medium

A

Prototrophs

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

This scientist showed that bacterial strains must make physical contact for transfer of genetic material to occur

A

Bernard Davis

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

Bernard Davis used this apparatus to show that bacteria must make physical contact to transfer genetic material

A

U-tube

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

This apparatus has a filter at the bottom with pores that are large enough to allow the passage of genetic material but small enough to prevent the passage of bacterial cells

A

U-tube

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

Can all species of bacteria conjugate?

A

No

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

Can only certain strains of bacteria act as donor cells in conjugation?

A

Yes

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

Certain donor strains of E. coli contain this small circular piece of DNA

A

F factor (fertility factor)

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

Bacteria strains containing an F factor are designated this

A

F+

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

Bacteria strains lacking an F factor are designated this

A

F-

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

Genes that play a role in DNA transfer are named either of these two prefixes

A

tra or trb followed by a capital letter

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

What initiates conjugation between bacteria cells?

A

Contact between donor and recipient cells

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

These act as attachment sites for F- minus bacteria onto F+ bacteria

A

Sex pili (or F pili)

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

Once contact is made and the pili shorten, donor and recipient bacteria cells are drawn together and this forms between the two cells

A

Conjugation bridge

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

During conjugation, this recognizes the origin of transfer (DNA sequence) and makes a cut in the DNA

A

Relaxosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

This protein remains bound to the end of the T-DNA after most accessory proteins of the relaxosome are released

A

Relaxase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

This is a complex of 10 to 15 proteins encoded by the F factor that span both inner and outer membranes and pumps DNA/relaxase into the recipient cell

A

Exporter

32
Q

This is the general term used to describe extra-chromosomal DNA

A

Plasmid

33
Q

Do plasmids replicate independent of bacterial chromosomes?

A

Yes

34
Q

Plasmids can exist as a single copy or up to 100 copies per cell, depending on this

A

Strength of origin

35
Q

Are plasmids usually required for survival?

A

No

36
Q

Plasmids can provide these to bacteria

A

Growth advantages

37
Q

What are the five different categories of plasmids?

A
  1. Fertility plasmids; 2. Resistance plasmids; 3. Degradative plasmids; 4. Col-plasmids; 5. Virulence plasmids
38
Q

This category of plasmids allows conjugation

A

Fertility plasmids

39
Q

This category of plasmids contain genes conferring resistance to antibiotics

A

Resistance plasmids

40
Q

This is another term for resistance plasmids

A

R factors

41
Q

This category of plasmids carries genes allowing digestion of unusual substances

A

Degradative plasmids

42
Q

This category of plasmids contain genes that kill other bacteria

A

Col-plasmids

43
Q

This category of plasmid carries genes that turn bacterium into pathogenic strains

A

Virulence plasmids

44
Q

In the 1950s, this scientist discovered a strain of E. coli that was very efficient at transferring chromosomal genes

A

Luca Cavalli-Sforza

45
Q

Luca Cavalli-Sforza discovered a strain of E. coli that was very efficient at transferring chromosomal genes and he designated it this

A

Hfr (high frequency of recombination)

46
Q

F factors that were excised imprecisely and carry genes that were found on the bacterial chromosome are called this

A

F’ factors (F prime factors)

47
Q

This scientist demonstrated that conjugation between an Hfr and an F- strain involves the transfer of a portion of the Hfr bacterial chromosome

A

William Hayes

48
Q

How long does it take for the entire Hfr chromosome to be passed into the F- cell during conjugation?

A

1.5 - 2 hours

49
Q

Do most conjugations take less than the full 1.5-2 hours?

A

Yes

50
Q

Because most conjugations take less than the full 1.5-2 hours, only a portion of this chromosome gets into the F- cell

A

Hfr chromosome

51
Q

Chromosomal material from Hfr cell can recombine with this in the recipient cell

A

Homologous region on chromosome of recipient cell

52
Q

This technique to map chromosomes was developed by Elie Wollman and Francois Jacob in the 1950s

A

Interrupted conjugation technique

53
Q

These two scientists developed the interrupted conjugation technique in the 1950s

A

Elie Wollman and Francois Jacob

54
Q

What is the rationale behind the interrupted conjugation technique?

A

The time it takes genes to enter the recipient cell is directly related to their order along the bacterial chromosome

55
Q

In the interrupted conjugation technique, the order of genes along the chromosome can be deduced by determining this

A

The length of time it takes to transfer certain genes

56
Q

How long is the E. coli genetic map?

A

100 minutes

57
Q

This is a virus that specifically infects bacterial cells

A

Bacteriophage

58
Q

A bacteriophage is composed of genetic material surrounded by this

A

Protein coat

59
Q

Bacteriophages may follow one or both of these two different cycles

A

Lytic and lysogenic

60
Q

This scientist discovered bacterial transformation in 1928 while working with strains of Streptococcus pneumoniae

A

Frederick Griffith

61
Q

What are the two types of bacterial transformation?

A

Natural and artificial

62
Q

Bacterial cells that are able to take up DNA are termed this

A

Competent cells

63
Q

Competent bacterial cells carry genes that encode these proteins

A

Competence factors

64
Q

Competence factors are proteins that facilitate this

A

Binding/uptake/incorporation of DNA into bacterial chromosome

65
Q

This enzyme cuts extracellular environmental DNA into smaller fragments

A

Endonuclease

66
Q

Are both extracellular DNA strands cut by endonuclease transported into the recipient cell?

A

No (one is degraded and the other enters cell)

67
Q

This is a region of mismatch caused by sequence differences between two alleles during transformation

A

Heteroduplex

68
Q

If the transformed DNA is homologous to a region in the bacterial chromosome, it can be incorporated through this process

A

Homologous recombination

69
Q

If the transformed DNA is not homologous to any genes on the chromosome, it may be incorporated at a random site on the chromosome through this process

A

Nonhomologous recombination

70
Q

Streptococcus pneumoniae secretes this, which leads to competence only when many cells of the same species are nearby

A

Competence-stimulating peptide

71
Q

Some species use these to preferentially take up DNA

A

DNA uptake signal sequences

72
Q

How many base pairs long are DNA uptake signal sequences?

A

9 or 10 bp

73
Q

How many times are DNA uptake signal sequences repeated throughout a bacterial genome?

A

1,000 - 2,000 times

74
Q

This is a common method to artificially induce bacterial transformation

A

Treat with calcium chloride and high temperature shock to make cells permeable to small DNA molecules

75
Q

This artificial transformation method makes cells permeable with an external electrical field

A

Electroporation

76
Q

Horizontal gene transfer has dramatically contributed to this

A

Acquired antibiotic resistance

77
Q

Some strains of this bacterial species are resistant to methicillin and all penicillins

A

Staphylococcus aureus