Genome and mutations

Question 1

Any change in the information content of genetic material

Answer 1

Mutation

Question 2

A change in the identity of an single base at a specific position in a nucleic acid sequence.

Answer 2

Point mutation

Question 3

A point mutation involving the replacement of a purine base by another purine base or of a pyrimidine base by another pyrimidine base.

Answer 3

Transition

Question 4

A point mutation involving the replacement of a purine base by a pyrimidine base or vice versa.

Answer 4

Transversion

Question 5

What is the difference between missense and nonsense mutations?

Answer 5

Missense converts a codon specifiying an amino acid to another codon specifying a different amino acid. Nonsense converts a codon specifying an amino acid to a stop codon, which prematurely terminates translation.

Question 6

Mutation that converts a stop codon into a codon that specifies an amino acid, causing translation to proceed beyond the codon

Answer 6

Readthrough

Question 7

Mutation that inserts or deletes one or more nucleotide residues within a codon sequence, resulting in a shift in the reading frame of the sequence downstream.

Answer 7

Frameshift

Question 8

Which of the following refers to the term, genome?

A. All genes 
B. All nuclear genes 
C. All nuclear and organellar genes 
D. All DNA sequences in haploid chromosomes 
E. All nuclear DNA

Answer 8

D

Question 9

In comparative genomics, what aspects of the organism are being compared?

A. Metabolites
B. Genes
C. DNA sequences
D. Protein sequences

Answer 9

C

Question 10

Which of the following would result from a silent mutation in a gene?

A. A truncated protein
B. A shift in the translational reading frame
C. The nucleotide sequence of the mRNA encoded by the gene remains unchanged
D. The amino acid sequence of the protein encoded by the gene remains unchanged

Answer 10

D

Question 11

BLAST of your unknown protein gave a hit in the database for proteinase K with an e value of e—100 Which of the following would BEST characterize the genes encoding these two proteins?

A. They are functionally unrelated.
B. They function in the same tissue.
C. They encode a dimeric protein complex
D. They are derived from similar species.

Answer 11

D

Question 12

Which of the following would BEST explain why in bacterial production of mammalian proteins, a cDNA is used rather than genomic DNA?

A. It is not possible to clone the entire coding region of the gene.
B. It is easier to clone cDNA than genomic DNA of comparable size.
C. It is easier to clone RNA than DNA.
D. Most eukaryotic genes have introns that cannot be removed in bacteria.

Answer 12

D

Question 13

Which of the following is of LEAST importance in comparative genomics?

A. Subcellular structures
B. DNA sequences
C. Sequence alignment software
D. Sequence databases

Answer 13

A

Question 14

In which level of comparative genomics resolution does synteny fall?

A. High
B. Medium
C. Low
D. None of the above

Answer 14

C

Question 15

Which of the following drives a regulated endogenous mutation process?

A. Action of activation-induced cytidine deaminase (AID)
B. Spontaneous thymine-thymine dimerization
C. Activity of low fidelity polymerases
D. All of the above
E. A and C only

Answer 15

E

Question 16

Which of the following statements is INCORRECT?

A. Point mutations may result in the production of truncated gene products.
B. Point mutations may have no effect on translated amino acid sequences.
C. Point mutations may produce shifts in reading frame.
D. Insertion-deletion mutations may produce shifts in reading frame.

Answer 16

C

Question 17

Which of the following statements regarding comparative genomics is “INCORRECT”?

A. Gene orthologs in model organisms are utilized to correct defective human genes
B. Genomes of model organisms are compared for their evolutionary significance
C. Similarities in genomes define the “minimal genome concept” or the minimal gene set required for cellular life
D. Identification of gene orthologs helps annotate human genes
E. Mutations and associated phenotypic defects in model organisms help explain human genetic diseases

Answer 17

A

Question 18

Which of the following are NOT properties of genes?

A. only undergo translation into a protein or a polypeptide
B. can be turned on or off
C. always carries heritable information
D. be classified into types depending on the RNA polymerase acting on them
E. may contain a coding region flanked by untranslated regions

Answer 18

A

Question 19

Which of the following RNA are not directly involved in Class II gene expression?

 A. snRNA 
 B. rRNA 
 C. snoRNA
 D. mRNA 
 E. tRNA

Answer 19

C

Question 20

Which of the following statements DOES NOT characterize the human genome?

A. Its estimated haploid size is 3 billions base pairs
B. A large portion of the genome (41.7%) has no known molecular function
C. The average gene size is 27 000 base pairs.
D. Repetitive sequences (Alu, MIR, MER, LTR & LINE) comprise 35.3% of the genome.
E. Some regions remained unsequenced due to their A+T content.

Answer 20

E

Question 21

Which of the following statements is “CORRECT”?

A. There are more gene-coding sequences than junk genes in the human genome.
B. Telomeres and centromeres contain most of the household proteins.
C. Pseudogenes are important genome structures for rescuing gene malformation.
D. Alternative splicing accounts for more protein products relative to gene number.
E. The largest chromosome is the most gene-rich chromosome.

Answer 21

D

Question 22

Which of the following biologic samples is ideal for genomic analysis?

A. WBC
B. Sperm
C. Hair
D. RBC

Answer 22

A

Question 23

Which of the ff. statement does not refer to a gene?

A. Locatable region of a genomic sequence
B. Corresponds to the unit of inheritance
C. Associated with regulatory genes transcribed and other
functional sequence regions.
D. Region of the genome that is resistant to spontaneous
mutation
E. None of the above

Answer 23

E

Question 24

Which of the following statements is correct?

A. The cell’s genome includes the totality of the DNA found in the nucleus
B. Any region in the genome can be utilized to estimate evolution in time
C. There are more score-able traits in the DNA sequence vis-a-vis morphological features
D. Evolution implies that all genes mutate at equivalent rates
E. To insure organism survival, exons must mutate faster
than introns

Answer 24

C

Question 25

Which of the following is correct? A. Humans are the most intelligent organisms because they have the most number of genes B. Nuclear genes of organelle expression insures survival of prokaryotic-like structures in the cell C. The fetal gene must undergo massive “rearrangement” to support phenotypic changes with development D. The more genes an organism has, the better it is for organism protection E. Junk DNAs are plenty because the junk encode promote genomic stability

Answer 25

B

Question 26

Which of the following mutation diseases confers strategic advantage against infectious disease? ``` A. Leukemia B. Duchenne Muscle Dystrophy C. Hemophelia D. Sickle Cell Anemia E. Monogenic Diabetes ```

Answer 26

D

Question 27

Which of the following statements is/are FALSE? A. An insertion or deletion by itself always produces a change in nucleic acid length. B. An insertion or deletion always produces a shift in reading frame. C. A point mutation by itself never produces a shift in reading frame D. Both A and B

Answer 27

B

Question 28

Which of the following statements is/are FALSE? A. An example of transversion is mutation of guanine to cytosine. B. An example of transition is mutation of cytosine to thymine. C. Spontaneous deamination of cytosine yields thymine. D. Both A and C

Answer 28

C

Question 29

Which of the following statements is/are FALSE? A. Cyclobutane dimers are characteristic of DNA damage due to ultraviolet rays B. Creation of an AP site occurs in the course of base excision repair C. Creation of an AP site occurs in the course of nucleotide excision repair D. Both B and C

Answer 29

C

Question 30

Which among these is true if an exonic DNA mutation occurs in a gene that results to a premature stop codon? A. Polyadenylation of mRNA will not occur B. Intron excision will be disrupted C. mRNA will not be transported out of the nucleus D. Translated protein will be truncated

Answer 30

D

Question 31

Which of the following statements about DNA methylation is not true? A. Loss of CpG dinucleotides during the evolution of vertebrates increases the chance of gene control by methylation. B. DNA methylation patterns may be inherited. C. Unmethylated DNA increases the chance of a gene becoming active. D. DNA methylation patterns of ... throughout the development of an embryo to childbirth (Assigned person was not able to complete the statement)

Answer 31

C

Question 32

Which of the following describes the action of glucocorticoids? A. Glucocorticoids bind to sequences of RNA to block RNA modification. B. Glucocorticoids and their receptors act on response elements. C. Glucocorticoids bind to membrane receptors that send out secondary messengers to activate transcription factors. D. Glucocorticoids phosphorylation.

Answer 32

B

Question 33

Which of the ff are true about gene promoters A. Increase expression of certain genes B. May lie on the same or opposite DNA strand to the genes they control C. They determine where and if transcription begins D. Each gene has one and only one promoter

Answer 33

C

Question 34

Peptide hormones exert their influence on gene expression by initially binding to cell surface receptors secondary messengers like cAMP can cause a series of events resulting in the binding of CREB to cAMP response elements in the DNA. Which type of control of gene expression is this? ``` A. Epigenetic Control B. Transcriptional Control C. RNA Transport Control D. Post-Transcriptional Control E. Translational Control ```

Answer 34

B

Question 35

Proteins of the HSP family (heat-shock protein) have been found to facilitate accurate folding of polypeptides as they are being synthesized. If these molecular chaperones were to cease functioning, which of the following would likely occur? ``` A. Correct folding of polypeptides would continue at the same rate B. Increase in activity of proteasome C. Decrease in protein aggregates D. Decrease in ubiquitination ```

Answer 35

B

Question 36

Which of the ff about trans-acting factors is true? A. Are base sequences on the same strand of DNA as the gene they control B. Need to be located near their gene to exert their action C. Trans - acting factors may either suppress/ activate gene expression D. NOTA

Answer 36

C

Question 37

Histones are able to undergo which of the following modifications? ``` A. Acetylation B. Ubiquitination C. Methylation D. All of the Above E. A and B only ```

Answer 37

D

Question 38

A CpG Segment just proximal to the promoter of a tumor suppression gene what if it is amplified 100-fold, which of the following will occur? A. Increase in acetylation of the segment B. increase in protection of tumorgenesis C. Deactivation of the MecP2 Protein D. Decrease in likelihood of developing a tumor

Answer 38

D

Question 39

The expression of ferritin is controlled by an Iron Response Element (IRE) that is bound to mRNA. When Iron is abundant the IRE is released and binds to iron instead, and ferritin expression is increased. Which of the following is this an example of? ``` A. Epigenetic control B. transcriptional control C. RNA transport control D. post-transcriptional control E. translational control ```

Answer 39

E

Question 40

Which of the following statements is true about “thrifty genotype” hypothesis? A. The thrifty genes have been deleted from the human genome by evolution because of the availability of food in modern times. B. A century ago, according to this hypothesis, individuals with the “thrifty genes” had a better chance of surviving famine. C. The thrifty genes are detrimental in modern times when an individual goes on a diet D. none of the above is true

Answer 40

B