e2

Question 1

Probability of co-transduction useful tool for

Answer 1

genetic linkage studies of short regions of bacterial genome.

Question 2

F+ x F-

Answer 2

Two F+

Question 3

Hfr x F-

Answer 3

1 Hfr, 1 F- (no change)

Question 4

F’ x F-

Answer 4

Two F’ (rarely the F- becomes F+ if whole chromosome is transferred)

Question 5

F+

Answer 5

F factor : Present as separate circular DNA

Conjugation : Donor

Question 6

F-

Answer 6

F factor : Absent

Conjugation : Recipient

Question 7

Hfr

Answer 7

F factor : Present, integrated into bacterial chromosome

Conjugation : High-frequency donor

Question 8

F’

Answer 8

F factor : Present as separate circular DNA, carrying some bacterial genes

Conjugation : Donor

Question 9

Virulence plasmid

Answer 9

carry genes that turn bacterium into pathogenic strains

Question 10

Episome

Answer 10

genetic element that can insert into the bacterial chromosome or replicate as a circular plasmid

Question 11

Col-plasmids

Answer 11

Contain genes that kill other bacteria

Question 12

Degradative plasmids

Answer 12

Carry genes allowing digestion of unusual substances

Question 13

Resistance plasmids

Answer 13

known as R factors. Contain genes conferring resistance to antibiotics

Question 14

Fertility plasmids

Answer 14

Allow conjugation

Question 15

Plasmids

Answer 15

many dna sequences in bacteria are mobile and can be transferred between individuals & among species

plasmids are usually circular DNA molecules that replicate independently of the bacterial chromosome

Often carry antibiotic or bacteriophage resistance genes.

Plasmids are used in genetic engineering as gene transfer vectors.

Question 16

Conjugation

Answer 16

DNA transfer that occurs naturally via cytoplasmic bridge.

Transfer is detectable if wild-type DNA transferred into a mutant.

Question 17

Prototrophs

Answer 17

wild type

Question 18

Auxotrophs

Answer 18

Mutant

Question 19

Identifying mutant cell

Answer 19

1) Solid nutritional medium where every cell can grow (=complete or supplemented medium)

2) Print colonies to selection medium : only prototrophs (wild type) grow, auxotrophs (mutant) cannot grow