Lecture 11

Question 1

Define genetic recombination

Answer 1

Incorporation of new DNA into an organism, but not by sexual reproduction

Question 2

In transformation, does the donor die?

Answer 2

Yes, the donor dies and breaks apart, as does it’s DNA

Question 3

What is incorporation of new DNA into an organism through a method that is not sexual reproduction called?

Answer 3

Genetic recombination

Question 4

What happens during transformation?

Answer 4

A donor breaks apart, as does it’s chromosomes, and gets its DNA incorporated into another bacteria, called the recipient

Question 5

What are the two bacteria involved in transformation normally called?

Answer 5

The donor and the recipient

Question 6

What does the donor do in transformation?

Answer 6

Have itself and its DNA break apart

Question 7

What does the recipient do in transformation?

Answer 7

Incorporate the donor’s genetic material into its genome

Question 8

Define conjugation

Answer 8

Transfer of genetic material between two bacterial cells through a pilus

Question 9

What is the sex pilus?

Answer 9

A tube formed by an F+ bacterial cell that connects two bacterial cells together

Question 10

What are the mating types in conjugation?

Answer 10

It is based on the fertility factor, F+ and F-

Question 11

How many mating types are there in conjugation?

Answer 11

Two, F+ and F-

Question 12

Is an F+ cell capable of producing a sex pilus?

Answer 12

Yes, because it has the F factor

Question 13

Is an F- cell capable of making a sex pilus?

Answer 13

No, because it doesn’t have the F factor

Question 14

Is the F factor part of a bacteria’s DNA?

Answer 14

No, it is a plasmid

Question 15

What is a mathod of gene exchange between bacterial cells that is most anaologus to sexual reproduction?

Answer 15

Conjugation, because of the inclusion of a sex pilus

Question 16

Does conjugation have male and female mating types?

Answer 16

No, they have F+ and F- mating types

Question 17

How is an F+ cell different from an F- cell?

Answer 17

1. Has an F factor
2. Can produce a sex pilus
3. Is more negative that an F- cell

Question 18

How is an F- cell different from an F+ cell?

Answer 18

1. It does not have the F factor
2. Cannot produce a sex pilus
3. it is more positive than an F+ cell

Question 19

How to F+ cells find F- cells?

Answer 19

An F+ cell is more negative than and F- cell and is attracted to each other like magnets

Question 20

Does an F- cell have a genome?

Answer 20

Yes, it simply lacks the fertility factor plasmid

Question 21

Is the F factor capable of replicating itself?

Answer 21

Yes, it makes a copy of itself during conjugation to send to the F- cell

Question 22

Do cells break down during conjugation?

Answer 22

No, broken cells are involved in transformation

Question 23

At the end of conjugation, how many F+ cells do you have?

Answer 23

2, the original and the newly make F+ cell

Question 24

Do you have F- cells at the end of conjugation?

Answer 24

No, during conjugation F- cells become F+ after reviving the fertility factor

Question 25

What is the F factor?

Answer 25

It is the fertility factor in bacterial cells that allows them to make a sex pilus and exchange DNA and plasmids

Question 26

Can an F- cell exchange plasmids?

Answer 26

No, you need the F factor to produce the sex pilus required in sharing genetic material

Question 27

What is a plasmid?

Answer 27

It is a genetic structure in the bacterial cell that can code for things and replicate independently from the chromosomes

Question 28

Name 3 plasmids

Answer 28

1. Fertility factor 2. R (resistance) plasmids (RTF + R genes) 3. Beta-Lactamse

Question 29

How often can genome recombination happen in conjugation?

Answer 29

Very rarely, 1/100,000

Question 30

Can a cell have more than 1 plasmid?

Answer 30

Yes! It can have as many as it likes

Question 31

What does HFR stand for?

Answer 31

High Frequency Recombination

Question 32

Define High Frequency Recombination (HFR)

Answer 32

It is a bacterial cell that has incorporated its F factor into its genome and will pass part of the genome to pass through the sex pilus during recombination

Question 33

How long does HFR take?

Answer 33

About 90-100 minutes

Question 34

What is an episome?

Answer 34

A genome that has the fertility factor incorporated in it

Question 35

What is it called when a fertility factor is incorporated into a genome?

Answer 35

An episome

Question 36

When will you have the genome pass through the sex pilus?

Answer 36

during HFR (high frequency of recombination)

Question 37

During HRF, does the episome pass through the sex pilus first?

Answer 37

No, it will pass through last, if at all

Question 38

Does the genome break apart during HFR?

Answer 38

It does in the donor cell

Question 39

How many F+ cells do you have after HFR?

Answer 39

One, the recipient cell doesn't get the F factor

Question 40

How many F- cells do you have after HFR?

Answer 40

One, the recipient cell doesn't get the F factor

Question 41

True or false: Only 1 plasmid can be exchanged during conjugation

Answer 41

False, many plasmids can be exchanged

Question 42

True or False : Lots of plasmids can be exchanged during conjugation

Answer 42

True

Question 43

What does RTF stand for?

Answer 43

Resistance Transfer Factors

Question 44

What kind of gram cell is most likely to exchange resistance factors?

Answer 44

Gram -

Question 45

Where does the exchange of resistance factors happen most frequently?

Answer 45

In hospitals

Question 46

True or False: Gram - cells do not commonly exchange resistance factor

Answer 46

False

Question 47

What is Beta-Lactamase?

Answer 47

An enzyme that can break down antibiotics such as penicillin or cephalosporine

Question 48

What does cephalospoinase break down?

Answer 48

Cephalospoins

Question 49

What breaks down cephalospoines?

Answer 49

Cephalospoinease

Question 50

Name 3 bacteria that commonly exchange Beta-Lactamase

Answer 50

1. Cephalospoins 2. Staphylococci 3. Nisseria gonorrhea

Question 51

How is Beta-Lactamase transferred?

Answer 51

Conjugation

Question 52

What is transduction?

Answer 52

The process of transferring genetic material between cells through bacteriophages

Question 53

What is a bacteriophage?

Answer 53

A virus with bacterial DNA

Question 54

Define Lysogenic Conversion

Answer 54

A method of recombination, but that transfers viral DNA instead of bacterial DNA

Question 55

Why is lysogentic conversion bad?

Answer 55

It makes bacteria very dangerous

Question 56

Name some cells that have been affected by lysogentic conversion

Answer 56

1. Clostridium botulinum (a Type A poision) 2. Corynebacterium Diphteriae (has a toxin that damages the heart) 3. Streptococcus pyogenes (which can cause Scarlet Fever due to it producing an erythrogenic toxin)

Question 57

How has Lysogenic conversion made Clostridium botulinum worse?

Answer 57

Its made it into a Type A poison, potent enough to kill all the humans with a cup of it

Question 58

How has lysogenic conversion made Corynebacterium diphteriae worse?

Answer 58

Has allowed it to make a toxin that damages the heart

Question 59

How has lysogenic conversion made streptococcus pyogenes worse?

Answer 59

Had given it the ability to make an erythrogenic toxin which causes scarlet fever

Question 60

What cause Scarlet fever?

Answer 60

Streptococcus pyogenes

Question 61

What is the difference between Transduction and Lysogenic conversion?

Answer 61

Transduction transfers bacterial DNA and lysogenic conversion transfers viral DNA

Question 62

What are all 5 types of genetic recombination of DNA in bacteria cells?

Answer 62

Transformation, conjugation, HFR, transduction, lysogenic conversion