MCQs Flashcards
Within a eukaryote gene sequence, introns are:
A. sequences that are transcribed and translated into a polypeptide
B. sequences not transcribed
C. sequences transcribed but not translated
D. sequences necessary for replication
E. sequences involved in DNA replication.
C. sequences transcribed but not translated
The process of DNA replication is: A. very inaccurate B. flawless C. semi-conscientious D. remarkably accurate E. not measurable.
D. remarkably accurate
An open reading frame is a:
A. continuous sequence of a cell cytoskeleton
B. continuous uninterrupted sequence of codons which code for a polypeptide
C. sequence of codons which codes for tRNA
D. sequence of codons which codes for rRNA
E. sequence of codons which codes for an intron.
B. continuous uninterrupted sequence of codons which code for a polypeptide
A new mutation in a human is only of genetic consequence to the next generation if it occurs in: A. a somatic cell B. a brain cell C. a virus D. a germ line cell E. all cells
D. a germ line cell
In bacteria, large transposable, mobile genetic elements, which carry many genes, are known as: A. genomic islands B. recombinant islands C. virgin islands D. household islands E. replicon islands.
A. genomic islands
In bacteria, what is the name for groups of genes that are involved in the same metabolic pathway or functional characteristic, and are clustered together and under the control of a single regulatory component? A. genomic islands B. cistrons C. replicons D. operons E. telomeres.
D. operons
- In female mammals, one X chromosome is largely inactivated. The inactivated X chromosome has:
A. higher levels of acetylation of histone proteins
B. lower levels of acetylation of histone proteins
C. a lack of associated histone proteins
D. lower levels of DNA methylation
E. higher levels of DNA methylation.
E. higher levels of DNA methylation.
- Which of the following statements about eukaryote gene promoter sequences is correct?
A. promoters are located immediately adjacent to the genes they regulate and are considered to be part of the genes
B. promoters are located some distance downstream of the genes which they regulate
C. promoters are located some distance upstream of the genes which they regulate
D. promoters never contain a TATA box
E. promoters never contain a CAAT box.
A. promoters are located immediately adjacent to the genes they regulate and are considered to be part of the genes
Which of the following statements is not true?
A. hunchback (hb) and bicoid (bcd) are examples of maternal effect genes
B. HB-M and BCD proteins produced by these genes help establish positional information along the anterior-posterior axis in the early Drosophila embryo
C. the highest concentration of bicoid mRNA is at the anterior pole of the early Drosophila embryo
D. the highest concentration of hunchback mRNA is at the posterior pole of the early Drosophila embryo
E. translation of hunchback mRNA is blocked by NOS protein encoded by the nanos (nos) gene.
D. the highest concentration of hunchback mRNA is at the posterior pole of the early Drosophila embryo
- HOX genes in mammalian embryos are expressed to:
A. determine the anterior-posterior axis
B. determine the development of the brain and central nervous system only
C. define segments in the developing somites (segmental units of the spinal column) and central nervous system
D. determine the development of the hind limbs only
E. determine the development of the fore limbs only.
C. define segments in the developing somites (segmental units of the spinal column) and central nervous system
- In humans, HOX genes are found:
A. spread throughout the genome and located on most chromosomes
B. organised in four clusters located on four different chromosomes
C. organised in four clusters, two clusters located on each of two different chromosomes
D. closely linked together in a cluster on a single chromosome
E. spread throughout a single chromosome.
B. organised in four clusters located on four different chromosomes
Mutations can lead to: A. malignancy or cancer B. heritable defects C. ageing D. all of the above E. none of the above.
D. all of the above
Apoptosis or programmed cell death occurs:
A. at single cell level
B. in a group of cells
C. either at a single cell level or in a group of cells
D. at tissue level
E. at the organ level.
A. at single cell level
Ultraviolet (UV) radiation B and C induces: A. purine dimers B. pyrimidine dimers C. 6-4 photoproducts (6-4PP) D. both pyrimidine dimers and 6-4PP E. neither pyrimidine dimers nor 6-4PP.
D. both pyrimidine dimers and 6-4PP
The p53 gene is:
A. a tumour suppressor gene
B. known as ‘guardian of the genome’
C. mutated in approximately 60% of cancers
D. involved in a check point at the G1/ S border
E. all the above.
E. All of the above
16. Cancer is a multistage process which involves the following processes: A. initiation B. promotion C. progression D. metastasis E. all of the above.
E. all of the above.
For biomonitoring purposes, fluorescence in situ hybridisation or FISH technique is an efficient method to analyse:
A. chromosomal aberrations and aneuploidy
B. mutations in specific genes
C. DNA strand breaks
D. sister chromatid exchanges (SCEs)
E. DNA adducts.
A. chromosomal aberrations and aneuploidy
Which of the following base analogues is required when cells are grown under in vitro conditions for the analysis of sister chromatid exchanges (SCEs) for biomonitoring purposes? A. 5-bromodeoxyuridine (BrdU or BudR) B. uridine C. inosine D. all of the above E. none of the above.
A. 5-bromodeoxyuridine (BrdU or BudR)
When a chemical binds to DNA using covalent bonding, it is most appropriately known as: A. DNA artefact B. DNA modification C. DNA adduct D. DNA twist E. none of the above.
C. DNA adduct
DNA cloning vectors are small replicons capable of accepting an insert of: A. foreign DNA B. foreign protein C. foreign RNA D. carbohydrate E. lipid.
A. foreign DNA
Which of the following is a key component of producing copy or complementary DNA (cDNA) from messenger RNA (mRNA)? A. reverse polymerase B. forward polymerase C. reverse transcriptase D. forward transcriptase E. reverse transacetylase.
C. reverse transcriptase
Which of the following methods of screening a gene bank does not require expression of the target gene sequence for detection of the clone? A. immunological screening B. direct detection of enzyme activity C. nucleic acid probe hybridisation D. blue / white screening E. selective pressure.
E. selective pressure.
The optimal size range of oligo-nucleotide primers for PCR is about: A. 1 to 2 kilobases B. 6 to 10 bases C. 12 to 50 bases D. 100 to 200 bases E. 1 to 2 megabases.
C. 12 to 50 bases
A commonly used bacterial gene used to create bacterial fusion proteins is: A. beta-lactase B. beta-haemoglobin C. beta-phage D. beta-toxin E. beta-galactosidase.
E. beta-galactosidase.
