chapter 7

What is a plasmid? -A DNA molecule that can exist independently of the bacterial chromosome -A large circular chromosome found in bacteria -The location on the bacterial chromosome where DNA replication begins -A gene found in some bacteria that enables them to transfer DNA to other bacterial cells

-A DNA molecule that can exist independently of the bacterial chromosome

What is a competent cell? -A bacterial cell that can grow on minimal medium -A bacterial cell that can transfer its genetic material to other cells by conjugation -A bacterial cell that can take up foreign DNA -A bacterial cell that can be infected by bacteriophages

-A bacterial cell that can take up foreign DNA

What is the F factor that is found in F+ donor strains of E. coli? -A small circular segment of DNA that is separate from the circular -chromosome -A gene found on the circular chromosome -An extra chromosome that is not found in other strains

-A small circular segment of DNA that is separate from the circular -chromosome

What is a bacteriophage? -A bacterial cell that can take up foreign DNA from its environment -A type of growth medium for bacterial cells -A virus that infects bacteria -A dead bacterial cell

-A virus that infects bacteria

Which type of genetic transfer requires direct physical contact between two living bacterial cells? -Transduction -Conjugation -Transformation

-Conjugation

Which type of E. coli strain frequently transfers chromosomal genes to recipient bacterial cells? -virulent -Hfr -F+ -F-

-Hfr Reason: An HFR strain is formed when a plasmid recombines with the cells chromosome.

Why is genetic transfer advantageous to bacteria? -It always leads to the development of advantageous traits. -It increases the size of the population. -It increases genetic diversity. -It increases the size of the bacterial genome.

-It increases genetic diversity.

How do F+ and F- strains of E. coli differ from one another? -Only F+ strains contain an F factor. -Only F+ strains can be infected by bacteriophage. -Only F- strains require a nutritional supplement in their growth media.

-Only F+ strains contain an F factor.

What is required in order for genetic material to be transferred between two bacterial cells by conjugation? -Physical contact between the two cells -The death of one of the cells but not the other -A bacteriophage that can infect both cells

-Physical contact between the two cells

What is genetic transfer? -The transfer of genetic material between bacterial cells -The mechanism that occurs during a cross over between two genes -The conversion of a mutant allele to a wild-type allele -The rearrangement of genes within a chromosome

-The transfer of genetic material between bacterial cells

Which of the following are mechanisms that bacteria use for genetic transfer? -Fertilization -Transformation -Transduction -Meiosis -Conjugation

-Transformation -Transduction -Conjugation

Which of the following statements about transformation is correct? -Transformation is a natural process that has evolved in some species of bacteria. -Transformation is a natural process that occurs in some types of eukaryotic cells, but not in bacteria. -Transformation occurs only in bacteria that have been genetically engineered.

-Transformation is a natural process that has evolved in some species of bacteria.

Any process in which one bacterium transfers genetic material to another bacterium is called ______. -competence -infection -recombination -genetic transfer

-genetic transfer

For a given gene, a bacterial cell is usually ______. -diploid -polyploid -haploid

-haploid

In a bacterial conjugation experiment, the unit used for genetic mapping is the ______. -nanometer -minute -base pair -kilodalton

-minute Reason: Each minute corresponds to about 47,000 base pairs.

A DNA molecule that can exist independently of the bacterial chromosome is called a(n) ______. -plasmid -competence factor -pilus -episome

-plasmid

The traits of bacteriophages are governed by ______. -the genetic material of the bacterial cells that they infect -their own genetic material -environmental factors, not by genetic material

-their own genetic material Reason: Bacteriophages contain their own genetic material that governs the traits of the phage.

An Hfr bacterial strain is very efficient at ______. -producing new bacteriophages and releasing them into the environment -taking up foreign DNA from the environment -transferring genes from its chromosome to F— strains

-transferring genes from its chromosome to F— strains

A strain of E. coli that contains an F factor and can act as a conjugation donor is designated ____, and a strain that lacks the F factor may be a recipient and is designated ____.

Blank 1: F+ Blank 2: F-

DNA from the bacterial chromosome may be transferred from one cell to another if a(n) ____ cell conjugates with an F— cell.

Blank 1: Hfr or F'

A bacterium is typically _____ for a particular gene, meaning that it only has one copy of the gene.

haploid or monoploid

The unit of measure that is used for the distance between two genes on a bacterial chromosome is the _____

minute, time, or minutes

A virus that infects bacteria is called a(n) _____.

bacteriophage, phage, bacteriophages, or phages

In addition to their circular chromosome, strains of E. coli that can act as donors during conjugation contain a small circular segment of DNA called a(n) ____factor.

F, fertility, f+, f, or F+

True or false: Transformation, the uptake of foreign DNA by bacterial cells, does not occur in nature, but it is possible in genetically engineered bacterial strains.

False Reason: Transformation is a natural process that has evolved in some species of bacteria.

True or false: Bacteriophages contain their own genetic material, which governs the traits of the phage.

True

When does conjugation result in the transfer of part of the bacterial chromosome to recipient cells? When two Hfr strains conjugate with one another When an Hfr strain conjugates with an F- strain When two F- strains conjugate with one another When an F+ strain conjugates with an F- strain

When an Hfr strain conjugates with an F- strain Reason: An Hfr strain is formed when a plasmid recombines with the cells chromosome.

A bacterial cell that is able to take up foreign DNA from its environment is called a(n) ____cell.

competent or competant

Genetic transfer is advantageous to bacteria because it increases genetic ____.

diversity, variation, variants, variability, or variety

The three mechanisms that bacteria can use to transfer genetic material are ____,____ , and ____.

transformation, transduction, and conjugation