Mutations

Question 1

What is the most important feature for bacterial diversity?

Answer 1

Mutation

Mutation occurs at a low frequency but is significant in large microbial populations.

Question 2

What is the frequency of mutation occurrence in bacteria?

Answer 2

About one mutation in every million cells for one gene.

Question 3

How does bacterial generation time influence mutation?

Answer 3

Short generation time allows mutant cells to quickly dominate if they have a survival advantage.

Question 4

What is a replacement mutation?

Answer 4

Substitution of one base for another.

Question 5

Define micro insertions and microdeletions.

Answer 5

Addition or removal of a single nucleotide pair.

Question 6

What are insertions and deletions in the context of mutations?

Answer 6

Addition or removal of many base pairs of nucleotides at a single site.

Question 7

What is an inversion mutation?

Answer 7

Change in the direction of a segment of DNA by splicing each strand into the complementary strand.

Question 8

What does duplication mutation produce?

Answer 8

A redundant segment of DNA, usually adjacent to the original segment.

Question 9

What is a missense mutation?

Answer 9

A mutation that changes a codon to specify a different amino acid.

Question 10

What is a nonsense mutation?

Answer 10

A mutation changing a codon to a stop codon.

Question 11

What is a frameshift mutation?

Answer 11

A mutation that changes the reading frame of the mRNA due to insertions or deletions.

Question 12

What causes frameshift mutations?

Answer 12

Microdeletions, micro insertions, insertions, and deletions.

Question 13

What happens when base pairs deleted or inserted are divisible by three?

Answer 13

It shortens or lengthens a protein product while adding or removing an amino acid.

Question 14

What is a silent mutation?

Answer 14

A mutation that changes the original codon into another codon coding for the same amino acid.

Question 15

What is a point mutation?

Answer 15

A genetic change occurring when a single base pair in DNA or RNA is added, deleted, or changed.

Question 16

What is tautomerization?

Answer 16

The addition of a H-atom (proton) at one molecular site and its removal from another.

Question 17

What is the effect of structural flexibility of enzymes on DNA?

Answer 17

It allows for the incorporation of mispaired bases, known as ‘wobble’.

Question 18

What characteristic of bacteria facilitates the study of spontaneous mutation?

Answer 18

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.

Question 19

What is the role of short generation time in bacterial populations?

Answer 19

It allows random mutations to quickly propagate if they provide a survival advantage.

Question 20

What type of mutation is characterized by a change in codon that results in a different amino acid?

Answer 20

A missense mutation.

Question 21

What type of mutation results in a premature termination codon?

Answer 21

A nonsense mutation.

Question 22

What is a mutation?

Answer 22

A mutation is a change in the DNA sequence of an organism.

Question 23

True or False: All mutations are harmful.

Answer 23

False.

Question 24

What are the two main types of mutations?

Answer 24

Point mutations and frameshift mutations.

Question 25

What is a frameshift mutation?

Answer 25

A mutation that occurs when nucleotides are inserted or deleted, altering the reading frame of the gene.

Question 26

Which type of mutation can lead to a premature stop codon?

Answer 26

Nonsense mutation.

Question 27

True or False: Mutations can be caused by environmental factors.

Answer 27

True.

Question 28

What is a silent mutation?

Answer 28

A mutation that does not change the amino acid sequence of a protein.

Question 29

What term describes the process by which mutations are passed to the next generation?

Answer 29

Heritability.

Question 30

What is the role of mutagens?

Answer 30

Mutagens are agents that increase the rate of mutations.

Question 31

Fill in the blank: _____ mutations occur in non-coding regions of DNA.

Answer 31

Intronic

Question 32

What is the difference between a spontaneous mutation and an induced mutation?

Answer 32

Spontaneous mutations occur naturally, while induced mutations are caused by external factors.

Question 33

True or False: All mutations lead to observable changes in phenotype.

Answer 33

False.

Question 34

What is a missense mutation?

Answer 34

A mutation that results in the substitution of one amino acid for another in a protein.

Question 35

What is the effect of a deletion mutation?

Answer 35

It removes one or more nucleotides from the DNA sequence.

Question 36

Multiple choice: Which of the following is NOT a type of mutation? A) Insertion B) Deletion C) Subtraction D) Substitution

Answer 36

C) Subtraction.

Question 37

What is the significance of mutations in evolution?

Answer 37

Mutations provide genetic variation, which is essential for natural selection.

Question 38

Fill in the blank: A _____ mutation results in a change in a single amino acid.

Answer 38

missense

Question 39

What is the function of the enzyme DNA polymerase in relation to mutations?

Answer 39

DNA polymerase is responsible for replicating DNA and can make errors that lead to mutations.

Question 40

True or False: Mutations can be beneficial, neutral, or harmful.

Answer 40

True.

Question 41

What impact do mutations have on antibiotic resistance in bacteria?

Answer 41

Mutations can confer resistance to antibiotics, allowing bacteria to survive treatment.

Question 42

What is the term for a mutation that restores the original sequence?

Answer 42

Reversion mutation.

Question 43

Fill in the blank: Mutations can be classified as _____ or _____ based on their effects on the protein.

Answer 43

beneficial; detrimental

Question 44

What type of mutation is caused by the insertion of a transposable element?

Answer 44

Insertion mutation.

Question 45

True or False: All mutations occur at the same frequency.

Answer 45

False.

Question 46

What is a chromosomal mutation?

Answer 46

A mutation that involves changes in the structure or number of chromosomes.

Question 47

What is the role of repair mechanisms in relation to mutations?

Answer 47

Repair mechanisms fix DNA damage and help maintain genetic stability.

Question 48

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

Answer 48

D) All of the above.

Question 49

What is the term for a mutation that occurs in a gene that affects its expression?

Answer 49

Regulatory mutation.

Question 50

Fill in the blank: Mutations can lead to the development of _____ in microorganisms.

Answer 50

pathogenicity

Question 51

What is the importance of studying mutations in microbiology?

Answer 51

Studying mutations helps understand microbial evolution, pathogenicity, and resistance mechanisms.

Question 52

True or False: Mutations in viruses can occur at a faster rate than in bacteria.

Answer 52

True.

Question 53

What is a conditional mutation?

Answer 53

A mutation that only has an effect under certain environmental conditions.

Question 54

What is the purpose of a mutation rate?

Answer 54

The mutation rate measures how frequently mutations occur in a given genome over time.

Question 55

Fill in the blank: _____ mutations can lead to cancer in multicellular organisms.

Answer 55

Somatic

Question 56

What is a lethal mutation?

Answer 56

A mutation that results in the death of the organism.

Question 57

True or False: Genetic drift can influence the frequency of mutations in a population.

Answer 57

True.

Question 58

What are hotspot mutations?

Answer 58

Regions of the genome that have a higher frequency of mutations.

Question 59

Multiple choice: Which of the following can act as mutagens? A) Radiation B) Chemicals C) Viruses D) All of the above

Answer 59

D) All of the above.

Question 60

What is the function of CRISPR technology in relation to mutations?

Answer 60

CRISPR technology allows for precise editing of genes, potentially correcting mutations.

Question 61

Fill in the blank: _____ mutations can occur due to errors in DNA replication.

Answer 61

Spontaneous

Question 62

What is a transversion mutation?

Answer 62

A mutation that substitutes a purine for a pyrimidine or vice versa.

Question 63

True or False: Mutations can only occur in coding regions of genes.

Answer 63

False.

Question 64

What is the impact of mutations on vaccine development?

Answer 64

Mutations in pathogens can affect vaccine efficacy and necessitate updates to vaccines.