Exam 1 - Ch.7 - Microbial Genetics

Question 1

Small molecules of extra-chromosomal DNA that replicate independently.

Answer 1

plasmids

Question 2

Are plasmids essential for normal metabolism, growth, or reproduction?

Answer 2

NO

Question 3

What can plasmids do?

Answer 3

Can covert survival advantage.

Question 4

What are the 4 types of plasmids?

Answer 4

F plasmids
R plasmids
Bacteriocin factors
Virulence plasmids

Question 5

What are F plasmids?

Answer 5

Fertility factors - carry instructions for conjugation.

Question 6

What are R plasmids?

Answer 6

Resistance factors - carry genes for resistance to anitbiotics

Question 7

What are bacteriocin factors?

Answer 7

Carry genes for toxins called bacterions - can kill its competitors.

Question 8

What are virulence plasmids?

Answer 8

Carry instructions that enable bacteria to become pathogenic. “good bacteria go bad”

Question 9

What is it called when organisms replicate their genome and provide copies to descendants?

Answer 9

Vertical gene transfer

Question 10

What type of cells do we see vertical gene transfer?

Answer 10

Prokaryotes and Eukaryotes (normal process in both)

Question 11

What is it called when genes are acquired from other microbes of the SAME generations?

Answer 11

Horizontal gene transfer

Question 12

How does horizontal gene transfer work?

Answer 12

donor cell contributes part of genome to recipient cell - may be a different species.

Question 13

What are the three types of horizontal gene transfer (Prokaryotes)?

Answer 13

Transformation
Transduction
Bacterial conjugation

Question 14

Horizontal gene transfer where recipient cell takes up DNA from environment. (not specific - scavenger)

Answer 14

Transformation

Question 15

In transformation what are the cells that take up DNA called?

Answer 15

Competent (must have particular “skill set”)

Question 16

What type of horizontal gene transfer is transfer of DNA from one cell to another via a replicating virus called?

Answer 16

Transduction

Question 17

In transduction, what is it called when the transducing phage carries random DNA segment from donor to recipient?

Answer 17

Generalized transduction

Question 18

In transduction, what is it called when only certain DNA sequences are transferred?

Answer 18

Specialized transduction

Question 19

What is a virus that attacks bacteria called?

Answer 19

bacteriophage

Question 20

What is the phage with the donor DNA called?

Answer 20

Transducing phage

Question 21

In transduction, how is the donor DNA incorporated into the recipient’s chromosome?

Answer 21

By recombination

Question 22

The type of horizontal gene transfer that transfers DNA from one cell to another, mediated by conjugation pili?

Answer 22

Conjugation

Question 23

Donor cell in conjugation requires what type of plasmid?

Answer 23

F plasmid (F+)

Question 24

Does the recipient cell have F plasmid?

Answer 24

NO

Question 25

What happens during bacterial conjugation?

Answer 25

A strand of F plasmid DNA is transferred to the recipient and the recipient can now do bacterial conjugation as well. (“female” becomes “male”)