Genetic Transfer Flashcards
What is the term for the one-way passage of DNA from a donor to a recipient?
Genetic Exchange
Sometimes referred to as horizontal gene transfer
What is the process called when a bacterium takes up DNA from its environment?
Transformation
The ability to take up DNA is called competence
What are the two main outcomes when internalized DNA is taken up by a bacterium?
Recombines if there is homology or is degraded
Homology refers to similarity between the internalized DNA and the host genome
What is transduction in the context of genetic transfer?
Transfer of DNA via bacteriophages
Bacteriophages are viruses that infect bacteria
What is the main requirement for conjugation to occur between bacteria?
Intimate cell contact
This process is often described as ‘sexuality’ in bacteria via sex pilus
What are plasmids?
Extrachromosomal, circular double stranded segments of DNA
Plasmids can encode virulence factors and are present in most bacteria
What are R plasmids?
Plasmids that include genes conferring resistance to antimicrobial agents
Misuse of antimicrobials leads to the selection of bacteria with R plasmids. ntimicrobial misuse occurs when antibiotics are taken incorrectly, such as taking the wrong dose, taking them for the wrong length of time, or taking them for an illness they don’t treat. Misuse of antimicrobials contributes to antimicrobial resistance, which is when bacteria and other germs evolve to defeat the drugs designed to kill them
What is the term for the ability of a bacterial cell to uptake DNA from the environment?
Competence
What is the role of transposases?
Mediate transposition. Transposases are enzymes that move segments of DNA, called transposons, to different locations in a cell’s genome. Transposons, also known as “jumping genes”, are DNA segments that can move around within a cell’s genome. They can cause genetic mutations and alter the amount of DNA in a cell.
Transposition is a change in the location of genetic material
What is the term for the transmission of genetic material via bacteriophage gene vectors?
Transduction
What potential outcomes can result from the transposition of mobile genetic elements?
Insertion sequences, transposons, DNA rearrangements
DNA rearrangements include inversion, deletion, fusion, and amplification
What biomedical issue is partially caused by the horizontal transfer of resistance-conferring genes?
Antibiotic resistance
What is the process by which bacteriophage DNA integrates into a host chromosome?
Transduction
What mechanism do conjugative plasmids use to transfer genetic information?
Sex pilus
What do R plasmids confer to bacteria?
Resistance to antimicrobial agents
What does the ‘F factor’ refer to in bacteria?
Fertility factor. In bacteria, the “F factor” refers to the “fertility factor,” a piece of DNA (plasmid) that allows a bacterium to transfer genetic material to another bacterium through a process called conjugation; essentially, a bacterium with the F factor acts as a “donor” cell, while a bacterium lacking the F factor acts as a “recipient” cell.
It allows a bacterium to transfer genetic material through conjugation
What is an Hfr cell?
A bacterium with a conjugative plasmid integrated into its chromosomal DNA.
A high-frequency recombination cell (Hfr cell) (also called an Hfr strain) is a bacterium with a conjugative plasmid (for example, the F-factor) integrated into its chromosomal DNA. The integration of the plasmid into the cell’s chromosome is through homologous recombination.
What is genetic transfer?
The process by which genetic material is passed from one organism to another.
True or False: Genetic transfer can occur between different species.
True
What are the three main types of genetic transfer?
Transformation, transduction, and conjugation.
Fill in the blank: In __________, bacteria take up free DNA from their environment.
transformation
What is transduction?
The transfer of genetic material from one bacterium to another via a bacteriophage.
Which process involves direct transfer of DNA between two bacteria?
Conjugation
True or False: Conjugation requires physical contact between two bacterial cells.
True
What type of genetic material is often transferred during transformation?
Plasmids or chromosomal DNA.
What are plasmids?
Small, circular DNA molecules that can replicate independently of chromosomal DNA.
Fill in the blank: The process of __________ involves a virus infecting a bacterium and transferring DNA.
transduction
Name one method by which bacteria can acquire antibiotic resistance through genetic transfer.
Conjugation
What is the role of the F plasmid in conjugation?
It contains genes that enable the formation of a pilus for DNA transfer.
True or False: Genetic transfer can lead to genetic diversity in bacterial populations.
True
What is a bacteriophage?
A virus that infects bacteria.
Fill in the blank: During __________, a bacterium can take up DNA from a lysed cell.
transformation
What is horizontal gene transfer?
The transfer of genes between organisms in a manner other than traditional reproduction.
What is the significance of horizontal gene transfer in evolution?
It enables rapid adaptation and evolution by spreading advantageous traits.
True or False: Only prokaryotes can undergo genetic transfer.
False
What is the main difference between transformation and transduction?
Transformation involves uptake of free DNA, while transduction involves DNA transfer via a virus.
Fill in the blank: The process of __________ is often used in genetic engineering to introduce new genes into bacteria.
transformation
What does the term ‘competence’ refer to in bacterial transformation?
The ability of a bacterium to take up and incorporate foreign DNA.
What are R plasmids?
Plasmids that carry genes for antibiotic resistance.
True or False: All bacteria are naturally competent for transformation.
False
What is a pilus?
A hair-like structure that facilitates the transfer of DNA during conjugation.
Fill in the blank: __________ is a method of genetic transfer that involves the use of a vector.
Transduction
What is the lytic cycle in relation to transduction?
A viral reproductive cycle that results in the destruction of the host cell.
What is the lysogenic cycle?
A viral reproductive cycle where the viral DNA integrates into the host genome and is replicated without killing the host.
What is a transducing phage?
A bacteriophage that carries bacterial DNA from one host to another.
True or False: Genetic transfer can occur in both prokaryotes and eukaryotes.
True
What role do restriction enzymes play in genetic transfer?
They cut foreign DNA, protecting bacteria from invading viruses.
Fill in the blank: The __________ hypothesis suggests that horizontal gene transfer is a major factor in the evolution of prokaryotes.
lateral gene transfer
What is the importance of genetic transfer in biotechnology?
It allows for the manipulation of organisms for research, medicine, and industry.
What is a conjugative plasmid?
A plasmid that carries genes necessary for conjugation.
True or False: Genetic transfer can only occur between closely related organisms.
False
What is transformation efficiency?
The measure of how effectively a bacterium can take up foreign DNA.
Fill in the blank: __________ is the process by which a bacterium transfers genetic material to another bacterium through a pilus.
Conjugation
What is the significance of gene cassettes in genetic transfer?
They allow for the rapid acquisition and expression of new genes.
What does the term ‘gene transfer agents’ refer to?
Virus-like particles that mediate the transfer of DNA between bacteria.
True or False: Genetic transfer contributes to the spread of virulence factors among bacterial populations.
True
What impact does genetic transfer have on antibiotic resistance?
It facilitates the rapid spread of resistance genes among bacterial strains.
Fill in the blank: The __________ model explains how genetic material can be exchanged between bacteria and archaea.
horizontal gene transfer
What is the role of transformation in genetic engineering?
It allows scientists to introduce new genes into organisms.
What is the primary method of genetic transfer in bacteria?
Conjugation
Fill in the blank: __________ is the process by which bacteriophages can introduce new genetic material into bacteria.
Transduction
What is the significance of the discovery of CRISPR in relation to genetic transfer?
It provides a mechanism for bacteria to acquire immunity against viruses and can be used for gene editing.
