Microbiology Chapter 8.4-8.5 Pre-Lecture Assignment

In bacterial conjugation, F+ donor cells are high frequency recombinant (Hfr) cells when the _______ is integrated into the chromosome.

F factor

A(n) ______ cell has a separate fertility plasmid, whereas a(n) _____ cell has the F factor incorporated into its chromosome.

F+; Hfr

Bacterial conjugation is sexual reproduction.

False

What is commonly shared between bacteria through the process of conjugation?

Genes for virulence factors Resistance plasmids

Which cells have the F plasmid incorporated into their chromosome?

Hfr cells

Transfer of DNA that results in organisms acquiring new genes that did not come directly from parent organisms is called ______ gene transfer.

Horizontal

Match the definition of horizontal and vertical gene transfer. Instructions

Horizontal gene transfer: transfer of DNA from a source other than the parental organisms Vertical gene transfer: transfer of DNA from parent organisms during reproduction

______ mutations lead to cell dysfunction or death, while ______ mutations produce neither adverse nor helpful changes.

Lethal; neutral

Any change to the nucleotide sequence in the genome is called a(n)

Mutation

A ______ mutation results in early termination of the protein.

Nonsense

Donor and recipient bacterial cells are connected by a(n) ______________ during conjugation

Pilus

The structure indicated with an arrow that joins the two conjugating cells is a(n) ______.

Pilus

A small circular segment of DNA found in the cytoplasm of bacteria that is capable of independent replication and usually contains nonessential genes is called a(n) ______________________

Plasmid

Any substitution of a single nucleotide that does not change the DNA reading frame is called a(n) _________________________ mutation

Point

A change in the gene that encodes the lac repressor was detected such that the amino acid alanine was inserted into the polypeptide instead of the amino acid glycine. This mutation can be described by which two of the following?

Point mutation Missense mutation

An event in which one bacterium donates DNA to another bacterium, resulting in a strain that differs from both donor and recipient, is a type of genetic transfer called _______________________

Recombination

The transfer of genes from a donor to a recipient microorganism, forming a new strain different from both donor and recipient, is called ______________

Recombination

Which term refers to the transfer of genes from donor to recipient microorganisms?

Recombination

Which type of mutations are caused by random errors in DNA replication?

Spontaneous

_______ mutations occur when errors are made in DNA replication whereas _____ mutations are caused by exposure to radiation or chemical agents.

Spontaneous; induced

How do an Hfr cell and an F+ cell differ?

The plasmid is integrated into the chromosome of an Hfr cell but not in an F+ cell.

The production of toxins in some virulent strains of bacteria has been linked to bacteriophage genes that have been transferred by ______________

Transduction

The transfer of DNA via bacteriophages is called ___________________________

Transduction

Which method of genetic transfer involves bacteriophages?

Transduction

Which type of horizontal gene transfer has been linked to the virulence of bacteria such as Clostridium, Streptococcus pyogenes, and Corynebacterium diphtheriae?

Transduction

The introduction of genes into eukaryotic cells in a process similar to transformation is referred to as _______.

Transfection

If a microbiologist wanted to insert a human gene into a bacterial cell, which type of horizontal gene transfer would be a useful means of accomplishing this goal?

Transformation

The uptake of free DNA by competent bacterial cells is called

Transformation

Three methods of gene transfer in bacteria are conjugation, __________________, and transduction

Transformation

Transfection in eukaryotes is similar to ______________ in bacteria

Transformation

Which gene transfer method involves the uptake of free DNA by competent bacterial cells?

Transformation

Which two types of horizontal gene transfer do NOT require direct contact between the donor and the recipient cells?

Transformation Transduction

Conjugation is a conservative process, meaning that ______.

A copy of the DNA is being transferred is retained by the donor

What is a mutation?

A permanent inheritable alteration in the DNA sequence or content of a cell

Which describes a plasmid?

A small circular piece of DNA that replicates its nonessential genes independently of the chromosome

Which of the following statements regarding conjugation is true?

After conjugation, the recipient cell will be F+.

A phage is a virus that infects ______.

Bacteria

A(n) ______ is a bacterial virus involved in _______, a means of horizontal gene transfer.

Bacteriophage; transduction

A bacterial cell that can accept soluble DNA from the surrounding environment is described as ___________________

Competent

What type of bacterial cell can be transformed by DNA in the environment?

Competent cell

A pilus connects two bacterial cells to facilitate the transfer of genetic material during the process of

Conjugation

An important means for bacteria to directly transfer resistance plasmids from one cell to another is through the process of

Conjugation

An important means for bacteria to directly transfer resistance plasmids from one cell to another is through the process of ____________________

Conjugation

In bacteria, horizontal gene transmission through a pilus is called _________

Conjugation

In bacteria, horizontal gene transmission through a pilus is called _____________

Conjugation

Which of the following are methods of gene transfer in bacteria?

Conjugation Transduction Transformation

_______ involves the use of a connecting bridge, _______ requires a bacterial virus vector, and ______ entails transfer of naked DNA.

Conjugation; transduction; transformation

After conjugation, the donor bacterium generally retains a copy of the genetic material that has been transferred, making conjugation a(n) ______________ process

Conservative

A point mutation involves any substitution of a single nucleotide.

True