Explore topic-wise MCQs in Biochemistry.

This section includes 242 Mcqs, each offering curated multiple-choice questions to sharpen your Biochemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

Restriction enzymes are named for

A. the person who discovered
B. the bacterium they are derived from
C. the viral DNA that they attack
D. none of the above
Answer» C. the viral DNA that they attack
2.

Which type of restriction enzymes do not usually require ATP?

A. Type I
B. Type II
C. Type III
D. Type IV
Answer» C. Type III
3.

An example of a restriction fragment length polymorphism is

A. an Eco RI cuts DNA at a different sequence than Hind III
B. different length fragments of DNA resulting from loss or gain of a restriction site
C. cystic fibrosis results from a three base deletion in most cases but in other cases, other mutations are involved
D. all of the above
Answer» C. cystic fibrosis results from a three base deletion in most cases but in other cases, other mutations are involved
4.

Knockout mice are created by

A. mutagenizing a mouse and selecting for mutant offspring
B. creating a chimera by fusing cells from two different cell lines
C. infecting the mouse with a retrovirus
D. transfecting embryonic stem cells with an altered gene sequence
Answer» E.
5.

A plasmid

A. is a circular DNA molecule
B. always contains an origin of replication
C. usually contains one or more restriction sites
D. all of the above
Answer» E.
6.

Under which of the following conditions would population gene frequencies remain the same?

A. Selection for homozygotes
B. Small population size
C. Active migration between groups
D. Random mating
Answer» E.
7.

Plant transformation can be obtained by

A. combining plant and animal cells in culture
B. shooting DNA into plant cells with a gun
C. using the
D. bacterium to infect plant roots
E. infecting plants with a tobacco mosaic virus
Answer» C. using the
8.

An expression vector

A. always contains an origin of replication
B. usually contains a gene that confers antibiotic resistance to the bacterial host
C. always contains DNA segments for the regulation of mRNA production
D. all of the above
Answer» E.
9.

The unpaired nucleotides produced by the action of restriction enzymes are referred to have

A. sticky ends
B. single strands
C. restriction fragments
D. ligases
Answer» B. single strands
10.

Which of the following is not true of small inbreeding populations?

A. They tend to loose genetic diversity
B. There is an increased incidence of recessive diseases
C. Alleles may become fixed
D. Mutation is increased
Answer» E.
11.

Which of these genes codes for a protein that plays a role in growth?

A. DCP1
B. SCLC6A4
C. KRTHA1
D. GH1
Answer» E.
12.

Which of the following genetic diseases would be amenable to genetic engineering?

A. Down's syndrome
B. Muscular dystrophy
C. Cystic fibrosis
D. Cri du Chat
Answer» D. Cri du Chat
13.

X-rays cause

A. the formation of thymine dimers
B. ionization of water in the cell
C. heat
D. none of the above
Answer» C. heat
14.

The order for the construction of a cDNA fragment from mRNA is to

A. bind oligo-dT, treat with reverse transcriptase, digest with RNase, add G residues to the 3' end, bind oligo-dC, treat with DNA polymerase
B. treat with reverse transcriptase, digest with RNase, add G residues to the 3' end, bind oligo-dC, treat with DNA polymerase and bind oligo-dT
C. digest with RNase, add G residues to the 3' end, treat with reverse transcriptase, add G residues to the 3' end and treat with DNA polymerase
D. bind oligo-dC, treat with reverse transcriptase, digest with RNase, add G residues to the 3' end, bind oligo-dT and treat with DNA polymerase
Answer» B. treat with reverse transcriptase, digest with RNase, add G residues to the 3' end, bind oligo-dC, treat with DNA polymerase and bind oligo-dT
15.

The TP53 gene of chromosome 17 codes for a protein __________ .

A. that plays a role in the digestive process
B. involved in glucose transport
C. involved in the regulation of the cell cycle
D. that is like a white blood cell protein
Answer» D. that is like a white blood cell protein
16.

Which of the following pair will produce complementary sticky ends?

A. Eco RI & MspI
B. Msp I & HPA II
C. Sau 3A & Bam HI
D. Mbo I & Sau 3A
Answer» D. Mbo I & Sau 3A
17.

A human cDNA library

A. contains DNA for specific human proteins
B. contains DNA for virtually all of the human proteins in vectors
C. cannot be used to obtain human genes because it would be radioactive
D. none of the above
Answer» C. cannot be used to obtain human genes because it would be radioactive
18.

What enzyme forms covalent bonds between restriction fragments?

A. DNA primase
B. DNA helicase
C. DNA polymerase
D. DNA ligase
Answer» E.
19.

Which of the following can be diagnosed by amniocentesis?

A. Down's syndrome
B. Cystic Fibrosis
C. Sickle cell anemia
D. All of these
Answer» E.
20.

Which of the following techniques can be used to determine the defective gene and for developing cancer?

A. Western blot
B. Southern blot
C. Northern blot
D. Eastern blot
Answer» C. Northern blot
21.

The transfer of antibiotic-resistant genes from genetically engineered bacteria to disease-causing bacteria __________ .

A. would be of no concern if it occurred.
B. has occurred
C. can never occur
D. seems unlikely
Answer» E.
22.

Both DNA gel electrophoresis and SDS-PAGE of proteins are similar because

A. in both cases molecules migrate to the anode
B. both techniques rely on a constant charge to mass ratio
C. both techniques utilize the sieving properties of gels
D. all of the above
Answer» E.
23.

Some genetic diseases cannot be diagnosed by changes in restriction sites. Some of these can be detected by allele-specific oligonucleotide probes. These are

A. copies of the gene with an altered sequence so that a restriction site is inserted
B. mutagenized copies of a gene
C. short sequences that will hybridize only to a specific base sequence
D. PCR-amplified variable numbers of tandem repeats (VNTRs)
Answer» D. PCR-amplified variable numbers of tandem repeats (VNTRs)
24.

In order to insert a foreign gene into a plasmid, both must __________

A. have identical DNA sequences
B. originate from the same type of cell
C. be cut by the same restriction enzyme
D. be of the same length
Answer» D. be of the same length
25.

Which of these restriction enzymes produce blunt ends?

A. SaII
B. EcoRV
C. XhoI
D. HindIII
Answer» C. XhoI
26.

Isoschizomers recognize

A. same recognition sequence but different recognition site
B. same recognition site and recognition sequence
C. same recognition site and different recognition sequence
D. different recognition site and different recognition sequence
Answer» C. same recognition site and different recognition sequence
27.

Which of these genes codes for a protein that plays a role in white blood cell function?

A. DCP1
B. MPO
C. GLUT4
D. RP13
Answer» C. GLUT4
28.

The RP13 gene of chromosome 17 codes for a protein __________ .

A. involved in glucose transport
B. that is a component of hair and nails
C. involved in eye development
D. involved in the determination of personality
Answer» D. involved in the determination of personality
29.

Which of the following is correct in terms of determination of location of genetic traits?

A. Known protein coding sequences are too far apart to allow linkage determination for most new genes
B. Restriction sites allow DNAs to be digested
C. Protein-coding genes are always associated with a restriction pattern
D. None of the above
Answer» B. Restriction sites allow DNAs to be digested
30.

In gel electrophoresis, DNA molecules migrate from __________ to __________ ends of the gel.

A. negative ... positive
B. basic ... acidic
C. long ... short
D. positive to negative
Answer» B. basic ... acidic
31.

Restriction enzymes

A. protect bacteria from viral infection
B. cut DNA in a staggered fashion
C. cut DNAs producing a blunt end
D. all of the above
Answer» E.
32.

First discovered, Type II restriction endonuclease was

A. Hinf I
B. Eco K
C. Hind II
D. EcoRI
Answer» D. EcoRI
33.

When populations are small, gene frequencies can change from generation to generation and some alleles may become fixed in a population. This is called __________ .

A. assortative mating
B. inbreeding
C. heterosis
D. genetic drift
Answer» E.
34.

Recombinant plasmids are added to a bacterial culture that has been pretreated with _________________ ions.

A. iodine
B. magnesium
C. calcium
D. ferric
Answer» D. ferric
35.

Which observation was made by Avery, Macleod, and McCarty?

A. DNA is a duplex molecule
B. DNA can be taken up from medium
C. DNA can denature at high temperatures
D. DNA is more stable than RNA
Answer» C. DNA can denature at high temperatures
36.

The first recombinant DNA molecule was synthesized in the year ______________

A. 1962
B. 1972
C. 1982
D. 1992
Answer» C. 1982
37.

Which enzyme is used to join together two different types of DNA molecules?

A. ligase
B. endonuclease
C. exonuclease
D. protease
Answer» B. endonuclease
38.

EcoR1 exhibits a two-fold rotational symmetry.

A. True
B. False
Answer» B. False
39.

Which of the following enzymes in bacteria are responsible for restricting the growth of viruses?

A. restriction endonuclease
B. topoisomerase
C. gyrase
D. protease
Answer» B. topoisomerase
40.

Who developed the chemical techniques to synthesize polynucleotides?

A. Barbara McClintock
B. James Watson
C. Fredrick Sanger
D. H. Gobind Khorana
Answer» E.
41.

In gel electrophoresis, DNA molecules migrate from __________ to __________ ends of the gel.

A. negative ... positive
B. basic ... acidic
C. long ... short
D. positive to negative
Answer» B. basic ... acidic
42.

Which of the following bacterium is used for gene transfer in plants?

A. Agrobacterium
B. Azatobacter
C. Rhizobium
D. Ecoli
Answer» B. Azatobacter
43.

Tubulin is regulated by

A. binding of tubulin to tubulin mRNA
B. splicing of the tubulin transcript
C. binding of tubulin to the tubulin translational product
D. binding of tubulin to DNA
Answer» D. binding of tubulin to DNA
44.

First discovered, Type II restriction endonuclease was

A. Hinf I
B. Eco K
C. Hind II
D. EcoRI
Answer» D. EcoRI
45.

Recombinant DNA molecule is produced by ligating __________

A. Two DNA segments
B. Two m-RNA molecules
C. One m-RNA with one t-RNA
D. One m-RNA with DNA segment
Answer» B. Two m-RNA molecules
46.

In hybridization method, which of the following is pressed onto agar?

A. Silicon paper
B. Nitrocellulose paper
C. Filter paper
D. PVDF
Answer» C. Filter paper
47.

The precise biochemical activity of a protein is described in __________

A. Phenotypic function
B. Cellular function
C. Molecular function
D. Structural genomics
Answer» D. Structural genomics
48.

Which of the following increases gene expression as much as 200-fold?

A. TATA box
B. Insulator
C. Enhancer
D. CAAT box
Answer» D. CAAT box
49.

Which of the following codons is not a termination codon for protein synthesis?

A. UUU
B. UAG
C. UAA
D. UGA
Answer» B. UAG
50.

Genes of different species but possessing a clear sequence and functional relationship to each other are __________

A. Ortholog
B. Synteny
C. Paralog
D. Microarray
Answer» B. Synteny