(c) UTRs are present between the start codon and
stop codon.
(d) At the end of translation, the release factor binds
to the initiation codon.- Read the following statements and choose the correct
option.
A. Nitrogenous base is linked to the pentose sugar
through a N-glycosidic linkage.
B. Phosphate group is linked to 5’-OH of a nucleoside
through phosphoester linkage.
C. Two nucleosides are linked through 3’ – 5’
N-glycosidic linkage.
D. Negatively charged DNA is wrapped around
positively charged histone octamer to form
nucleosome.
E. The chromatin that is more densely packed and
stains dark is called euchromatin.
(a) A, B and C alone are wrong.
(b) D alone is wrong.
(c) C and E alone are wrong.
(d) A alone is wrong. - Which one of the following is correct?
(a) Introns are present in mRNA and exons are
present in tRNA.
(b) Codons are present in mRNA and anticodons in
tRNA.
(c) Every intron is a set of three terminator codons.
(d) Exons are present in eukaryotes while introns are
present in prokaryotes. - Match the codons with their respective amino acids
and choose the correct answer.
Codons Amino acids
A. UUU 1. Serine
B. GGG 2. Methionine
C. UCU 3. Phenylalanine
D. CCC 4. Glycine
E. AUG 5. Proline
(a) A – 3, B – 4, C – 1, D – 5, E – 2
(b) A – 3, B – 1, C – 4, D – 5, E – 2
(c) A – 3, B – 4, C – 5, D – 1, E – 2
(d) A – 2, B – 4, C – 1, D – 5, E – 3 - A mixture containing DNA fragments, A, B, C and D,
with molecular weights of A + B = C, A > B and D >
C, was subjected to agarose gel electrophoresis. The
positions of these fragments farthest from cathode and
nearest to anode sides of the gel would be
(a) B, A, C, D (b) A, B, C, D
(c) C, B, A, D (d) B, A, D, C. - Which DNA molecule among the following will melt
at lowest temperature?
(a) 5 ′ - A- A-T- G-C-T- G-C-3′
3 ′ - T -T- A-C-G-A-C-G-5′
(b) 5 ′- A-A-T-A-A-A-G-C-T-3′
3 ′- T- T- A-T- T- T- C-G-A-5′
(c) 5 ′-G-C-A-T- A-G-C-T-3′
3 ′-C-G-T- A-T-C- G-A-5′
(d) 5 ′- A-T- G- C- T- G-A-T-3′
3 ′- T- A-C-G-A- C- T- A-5′ - Given below are the steps of protein synthesis. Arrange
them in correct sequence and select the correct
option.
(i) Codon-anticodon reaction between mRNA and
aminoacyl tRNA complex.
(ii) Attachment of mRNA and smaller sub-unit of
ribosome.
(iii) Charging or aminoacylation of tRNA.
(iv) Attachment of larger sub-unit of ribosome to the
mRNA-tRNAMet complex.
(v) Linking of adjacent amino acids.
(vi) Formation of polypeptide chain
(a) (ii) → (i) → (iii) → (v) → (iv) → (vi)
(b) (v) → (ii) → (i) → (iii) → (iv) → (vi)
(c) (iii) → (ii) → (iv) → (i) → (v) → (vi)
(d) (iii) → (ii) → (i) → (iv) → (v) → (vi) - Arrange the various steps of DNA fingerprinting
technique in the correct order.
(i) Separation of DNA fragments by electrophoresis
(ii) Digestion of DNA by restriction endonucleases
(iii) Hybridisation using labelled VNTR probe
(iv) Isolation of DNA
(v) Detection of hybridised DNA fragments by auto
radiography
(vi) Transferring the separated DNA fragments to
nitrocellulose membrane
(a) (iv) → (ii) → (i) → (vi) → (iii) → (v)
(b) (iv) → (i) → (ii) → (iii) → (vi) → (v)
(c) (ii) → (i) → (iv) → (vi) → (iii) → (v)
(d) (iii) → (v) → (iv) → (ii) → (i) → (vi) - If Meselson and Stahl’s experiment is continued
for four generations in bacteria, the ratio of
(^15) N/15N: 15N/14N: 14N/14N containing DNA in the
fourth generation would be
(a) 1 : 1 : 0 (b) 1 : 4 : 0
(c) 0 : 1 : 3 (d) 0 : 1 : 7.