Genetics of Bacteria and Viruses 1

Question 1

Most of the cells ont his planet are ___

Answer 1

Prokaryotes

Question 2

Prokaryotes lack ___ and have __ __

Answer 2

Lack nuclei

Circular chromosomes

Question 3

Prokaryotes are comprised of ___ and ___

Answer 3

Bacteria and Archaea

Question 4

Bacteria have viruses called ___ or ___

Answer 4

Bacteriophages or phages

Question 5

How do prokaryotes multiply?

Answer 5

Binary fission

Question 6

How do bacteria carry their DNA?

Answer 6

A circular genome and circular plasmids

Question 7

What carries genes that influence bacteria traits?

Answer 7

Plasmids

Question 8

How many mechanisms for bacterial DNA transfer did we cover?

Answer 8

3

Question 9

What are the 3 mechanisms for bacterial DNA exchange?

Answer 9

Transformation

Transduction

Conjugation

Question 10

Transformation:

Answer 10

DNA is taken up from its environment

Question 11

Transduction:

Answer 11

Receiving DNA from viruses

Question 12

Conjugation:

Answer 12

receiving DNA from another cell

Question 13

Conjugation can result in transfer of ___ or ___

Answer 13

Plasmids or genomic DNA

Question 14

Vertical transmission:

Horizontal transmission:

Answer 14

Vertical - parents to offspring

Horizontal - between the same generation

Question 15

Donor F+ only transfers to

Answer 15

Receipient F^-

Question 16

Hfr:

Answer 16

High frequency recombination

Question 17

Hfr crosses to F^- strains=

Answer 17

Virtually no F-

Parents are converted to F+ or Hfr

Question 18

Normal F+ strains convert ___ ___ of F- parents into F+

Answer 18

Large fraction

Question 19

What are Hfr strains a result of?

Answer 19

F plasmid being integrated into the chromosome

Question 20

Double crossovers must occur in bacteria or __

Answer 20

the soul will be unviable

Question 21

The F plasmid can integrate into ___ ___of the E.coli chromosome

Answer 21

Specific regions

Question 22

What are the two outcomes of F- mediated conjugation?

Answer 22

F+ - independent circle of DNA

Hfr- plasmid has incorporated into chromosome

Question 23

Does a single crossover result in a viable recombinant?

Answer 23

No, it does NOT restore circular DNA

Question 24

F’ plasmids are a result of:

Answer 24

Popping out of chromosome and picking up genomic DNA with it

Question 25

Naturally competent:

Answer 25

Can take up DNA from the environment

Question 26

Free DNA being taken up is an ___ process

Answer 26

Active

Question 27

ssDNA that has been taken up may ___ into the chromosome

Answer 27

integrate

Question 28

Phage consists of:

Answer 28

A nucleic acid chromosome surrounded by a coat of protein molecules

Question 29

Some phages have ___ chromosomes while others have ___ chromosomes

Answer 29

DNA RNA

Question 30

How do phages share DNA with a cell?

Answer 30

Phages bind to the surface of a sell and inject their DNA into that cell

Question 31

A single phage can:

Answer 31

Hijack a cell and turn it into a factory for more phage

Question 32

h and r genes h influences: r determines:

Answer 32

h -whether a phage can infect two different E. coli strains r - whether the phage quickly or slowly trigers lysis

Question 33

How many types of different phages are there? What are they?

Answer 33

4 Virulent Temperate Prophage Lysogen

Question 34

Virulent:

Answer 34

They immediately lyse and kill the host

Question 35

Temperate:

Answer 35

Can remain within a host for a period without killing it

Question 36

Prophage:

Answer 36

A phage integrated into the hosts genome

Question 37

Lysogen:

Answer 37

A bacterium harboring a prophage

Question 38

Phage transduction:

Answer 38

Some phage can pick up bacterial DNA and transfer it to another cell

Question 39

Generalized transduction:

Answer 39

Transducing phage can carry any part of the bacterial chromosome

Question 40

Specialized transduction:

Answer 40

Transducing phage can only carry specific parts of the bacterial chromosome

Question 41

λ phage:

Answer 41

A specialized transducing phage that inserts by a crossover at a specific site in the genome

Question 42

If a cell WITHOUT (non hfr) λ prophage receives λ prophage: If a cell WITH (hfr) λ prophage receives λ prophage:

Answer 42

It will die It is immune

Question 43

λ prophage can pops out of genome:

Answer 43

No genetic change in the host and the phage is complete

Question 44

Rare λ prophage outlooping:

Answer 44

Incomplete phage genome that contains some bacterial DNA

Question 45

Plasmids often carry transposable elements Transposon:

Answer 45

A sequence that can be translocated even in the absence of complementary sequence in the host DNA