Mutations Flashcards
What is the most important feature for bacterial diversity?
Mutation
Mutation occurs at a low frequency but is significant in large microbial populations.
What is the frequency of mutation occurrence in bacteria?
About one mutation in every million cells for one gene.
How does bacterial generation time influence mutation?
Short generation time allows mutant cells to quickly dominate if they have a survival advantage.
What is a replacement mutation?
Substitution of one base for another.
Define micro insertions and microdeletions.
Addition or removal of a single nucleotide pair.
What are insertions and deletions in the context of mutations?
Addition or removal of many base pairs of nucleotides at a single site.
What is an inversion mutation?
Change in the direction of a segment of DNA by splicing each strand into the complementary strand.
What does duplication mutation produce?
A redundant segment of DNA, usually adjacent to the original segment.
What is a missense mutation?
A mutation that changes a codon to specify a different amino acid.
What is a nonsense mutation?
A mutation changing a codon to a stop codon.
What is a frameshift mutation?
A mutation that changes the reading frame of the mRNA due to insertions or deletions.
What causes frameshift mutations?
Microdeletions, micro insertions, insertions, and deletions.
What happens when base pairs deleted or inserted are divisible by three?
It shortens or lengthens a protein product while adding or removing an amino acid.
What is a silent mutation?
A mutation that changes the original codon into another codon coding for the same amino acid.
What is a point mutation?
A genetic change occurring when a single base pair in DNA or RNA is added, deleted, or changed.
What is tautomerization?
The addition of a H-atom (proton) at one molecular site and its removal from another.
What is the effect of structural flexibility of enzymes on DNA?
It allows for the incorporation of mispaired bases, known as ‘wobble’.
What characteristic of bacteria facilitates the study of spontaneous mutation?
Haploidy and a highly studied genome. Haploidy is a state where a cell has one set of chromosomes, instead of the two sets that is typical. Haploid cells are useful for genetic analysis because it’s easier to manipulate genes in them.
What is the role of short generation time in bacterial populations?
It allows random mutations to quickly propagate if they provide a survival advantage.
What type of mutation is characterized by a change in codon that results in a different amino acid?
A missense mutation.
What type of mutation results in a premature termination codon?
A nonsense mutation.
What is a mutation?
A mutation is a change in the DNA sequence of an organism.
True or False: All mutations are harmful.
False.
What are the two main types of mutations?
Point mutations and frameshift mutations.
What is a frameshift mutation?
A mutation that occurs when nucleotides are inserted or deleted, altering the reading frame of the gene.
Which type of mutation can lead to a premature stop codon?
Nonsense mutation.
True or False: Mutations can be caused by environmental factors.
True.
What is a silent mutation?
A mutation that does not change the amino acid sequence of a protein.
What term describes the process by which mutations are passed to the next generation?
Heritability.
What is the role of mutagens?
Mutagens are agents that increase the rate of mutations.
Fill in the blank: _____ mutations occur in non-coding regions of DNA.
Intronic
What is the difference between a spontaneous mutation and an induced mutation?
Spontaneous mutations occur naturally, while induced mutations are caused by external factors.
True or False: All mutations lead to observable changes in phenotype.
False.
What is a missense mutation?
A mutation that results in the substitution of one amino acid for another in a protein.
What is the effect of a deletion mutation?
It removes one or more nucleotides from the DNA sequence.
Multiple choice: Which of the following is NOT a type of mutation? A) Insertion B) Deletion C) Subtraction D) Substitution
C) Subtraction.
What is the significance of mutations in evolution?
Mutations provide genetic variation, which is essential for natural selection.
Fill in the blank: A _____ mutation results in a change in a single amino acid.
missense
What is the function of the enzyme DNA polymerase in relation to mutations?
DNA polymerase is responsible for replicating DNA and can make errors that lead to mutations.
True or False: Mutations can be beneficial, neutral, or harmful.
True.
What impact do mutations have on antibiotic resistance in bacteria?
Mutations can confer resistance to antibiotics, allowing bacteria to survive treatment.
What is the term for a mutation that restores the original sequence?
Reversion mutation.
Fill in the blank: Mutations can be classified as _____ or _____ based on their effects on the protein.
beneficial; detrimental
What type of mutation is caused by the insertion of a transposable element?
Insertion mutation.
True or False: All mutations occur at the same frequency.
False.
What is a chromosomal mutation?
A mutation that involves changes in the structure or number of chromosomes.
What is the role of repair mechanisms in relation to mutations?
Repair mechanisms fix DNA damage and help maintain genetic stability.
Multiple choice: Which of the following is a potential outcome of a mutation? A) No effect B) Beneficial effect C) Harmful effect D) All of the above
D) All of the above.
What is the term for a mutation that occurs in a gene that affects its expression?
Regulatory mutation.
Fill in the blank: Mutations can lead to the development of _____ in microorganisms.
pathogenicity
What is the importance of studying mutations in microbiology?
Studying mutations helps understand microbial evolution, pathogenicity, and resistance mechanisms.
True or False: Mutations in viruses can occur at a faster rate than in bacteria.
True.
What is a conditional mutation?
A mutation that only has an effect under certain environmental conditions.
What is the purpose of a mutation rate?
The mutation rate measures how frequently mutations occur in a given genome over time.
Fill in the blank: _____ mutations can lead to cancer in multicellular organisms.
Somatic
What is a lethal mutation?
A mutation that results in the death of the organism.
True or False: Genetic drift can influence the frequency of mutations in a population.
True.
What are hotspot mutations?
Regions of the genome that have a higher frequency of mutations.
Multiple choice: Which of the following can act as mutagens? A) Radiation B) Chemicals C) Viruses D) All of the above
D) All of the above.
What is the function of CRISPR technology in relation to mutations?
CRISPR technology allows for precise editing of genes, potentially correcting mutations.
Fill in the blank: _____ mutations can occur due to errors in DNA replication.
Spontaneous
What is a transversion mutation?
A mutation that substitutes a purine for a pyrimidine or vice versa.
True or False: Mutations can only occur in coding regions of genes.
False.
What is the impact of mutations on vaccine development?
Mutations in pathogens can affect vaccine efficacy and necessitate updates to vaccines.
