Genetic Analysis and Mapping in Bacteria and Bacteriophages

Question 1

Bacteriophages

Answer 1

Viruses that use bacteria as their host

Question 2

the function of pure cultures are

Answer 2

that they give rise to cells that exhibit heritable variation with respect to growth under salient/unique conditions

Question 3

Minimal medium

Answer 3

composed of organic carbon source (glucose or lactose) plus ions present as inorganic salts

Question 4

These organisms can synthesize essential nutritional components and survive in minimal medium

Answer 4

Phototrophs

Question 5

Auxotrophs are

Answer 5

Bacterium that lose the ability to synthesize one or more organic components through mutation

Question 6

Genetic Recombination in Bacteria happens through the transfer of genetic information between individual organisms (True or False)

Answer 6

True

Question 7

Vertical Gene Transfer is the transfer occurring between unrelated cells (True or False)

Answer 7

False(Answer: Horizontal Gene Transfer)

Question 8

Conjugation, Transformation, and Transduction are all parts of Horizontal gene transfer (True or False)

Answer 8

True

Question 9

process of the genetic information of one bacterium transferred and recombined with the genetic information of another bacterium

Answer 9

conjugation

Question 10

What type of E.coli was used in F+ and F- strain experiment

Answer 10

E.coli K12

Question 11

The mechanism of the Davis U-Tube experiment concluded that

Answer 11

physical contact between cells of the 2 strains is essential to genetic recombination

Question 12

What brings about physical contact between bacteria?

Answer 12

sex pilus

Question 13

F Factor

Answer 13

plasmid confers fertility and contains genes essential for sex pilus formation which genetic recombination depends and confers the ability to donate part their chromosome

Question 14

Consist of 2 components: The resistance transfer factor (RTF) and more r-determinants

Answer 14

R Plasmid

Question 15

r -determinants

Answer 15

genes that confer resistance to antibiotics or mercury

Question 16

encodes genetic information essential to transferring plasmid between bacteria

Answer 16

RTF

Question 17

Encodes one or more proteins highly toxic to bacterial strains that do not harbor the same plasmid and is not usually transmissable

Answer 17

Col plasmid

Question 18

Highly toxic protein to bacterial strains that do not harbor the same plamid

Answer 18

colicins

Question 19

How were Hfr bacteria made?

Answer 19

treated the F+ strain with nitrogen mustard which induced mutations. The cells treated were genetically altered and underwent recombination at a rate of 1/104 or 10-4, 1000 times more frequently than the original F+ strains

Question 20

Hfr bacteria

Answer 20

Genetically altered F+ strains that undergo recombination at a much greater rate

Question 21

How was the E.coli mapped?

Answer 21

Hfr and F- strains with suitable marker genes were mixed, and recombination of specific genes was assayed at different times.

Question 22

interrupted mating technique

Answer 22

A gene mapping technique in which bacterial conjugation is disrupted after specified time intervals

Question 23

Time mapping

Answer 23

the chromosome of a bacteria is transferred linearly and the gene order and distance between genes is measured in minutes

Question 24

The point of origin differs from strain to strain (True or False)

Answer 24

True

Question 25

What determines the point of origin (O)

Answer 25

in Hfr strains, the F factor integrates into the chromosome at different points, and its position determines the site of O.

Question 26

How does donor DNA replace the homologous region in the recipient chromosome?

Answer 26

rec (recombination) genes: recA, recB, recC & recD.

Question 27

Plays an important role in recombination involving either a single-stranded DNA molecule or the linear end of a double-stranded DNA molecule that has unwound

Answer 27

recA protein

Question 28

important when double-stranded DNA serves as the source of genetic recombination.

Answer 28

recBCD protein

Question 29

Transformation

Answer 29

Small pieces of extracellular DNA are taken in by a bacterium leading to a stable genetic change

Question 30

for bacteria, the linkage is the proximity of genes that permits cotransformation (True or False)

Answer 30

True

Question 31

The frequency of 2 unlinked genes being transformed simultaneously is much higher than if they are linked (True or False)

Answer 31

False

Question 32

Bacteriophages structure

Answer 32

The head is connected to a tail that contains a collar & contractile sheath surrounding a central core.

Question 33

phage construction is a combination of self-assembly & enzyme-directed processes (true or false)

Answer 33

true

Question 34

plaque assay

Answer 34

the technique used in mutational & recombinational studies of bacteriophages

Question 35

Lysogeny

Answer 35

type of life cycle that takes place when a bacteriophage infects certain types of bacteria

Question 36

Transduction cannot be used for mapping (True or False)

Answer 36

False (Answer: 2 genes that closely align (linked) on the bacterial chromosome can be simultaneously transduced, a process called co-transduction. this can be used for mapping)