30 .Read the following statements and choose the correct
option. [Kerala CEE 2014]
I.RNA polymerase associates transiently with ‘Rho’
factor to initiate transcription.
II.In bacteria, transcription and translation takes
place in the same compartment.
III.RNA polymerase-I is responsible for transcription
of tRNA.
IV.When hnRNA undergoes capping process,
adenylate residues are added at 3 ′-end in a
template independent manner.
V.hnRNA is the precursor of mRNA.
(a) Only II (b) II, III and IV (c) III and IV (d) I and V
31 .The diagram shows an important concept in the
genetic implication of DNA. Fill in the blanks A to C.
[NEET 2013]
DNA A RNA B Protein Proposed by
C
→ m → →
(a) A–transcription, B–replication, C–James Watson
(b) A–translation, B–transcription, C–Erwin Chargaff
(c) A–transcription, B–translation, C–Francis Crick
(d) A–translation, B–extension, C–Rosalind Franklin
32 .If a segment of an mRNA molecule has the sequence
5 ′GUACCGAUCG 3 ′, which of the following could have
been the template DNA molecule? [AIIMS 2013]
(a) 5 ′-GCUAGCCAUG- 3 ′ (b) 5 ′-GUACCGAUGG- 3 ′
(c) 5 ′-CATGGCTAGC- 3 ′ (d) 5'-CGATCGGTAC- 3 ′
33 .Which of the following recognises the start signal on
DNA to initiate transcription
(a) TATA box (b) Sigma factor
(c) Core enzyme (d) Operation
34 .After transcription, a primary transcript of RNA
complementary to DNA is released. What would be the
most likely fate of this transcript before being used for
translation and coding of proteins.
I.Removal of exons
II.Methylguanosine cap at 5 ′ end
III.Poly A tail at 3 ′ end
IV.Methylguanosine cap at 5 ′ end
V.Removal of introns.
(a) I, III and IV(b) II, IV and V (c) II, III and V(d) IV and V
35 .Select the correct statements regarding mRNA stability
I.Prokaryotic mRNA have a half-life of only a few
minutes.
II.Regulation of mRNA stability is a way of regulating
gene expression.
III.Poly A tails stabilise eukaryotic mRNAs.
IV.Histone mRNA have especially long poly A tails
(a) I and IV (b) I, II and III (c) Only IV (d) II and III
36 .In eukaryote, RNA polymerase-II transcribe
(a) hnRNA (b) 18 S rRNA
(c) 28 S rRNA (d) snRNA
37 .If one strand of DNA has the nitrogenous base
sequence as ATCTG, what would be the
complementary RNA strand sequence?
[CBSE AIPMT 2012]
(a) TTAGU (b) UAGAC (c) AACTG (d) ATCGU
38 .Which one of the following is not a part of transcription
unit in DNA? [CBSE AIPMT 2012]
(a) The inducer (b) A terminator
(c) A promoter (d) The structural gene
39 .Which of the following is a correctly described
characteristic of genetic code?
(a)Degenerate – One amino acid has more than one triplet
code
(b)Universality – Given codon specifies same amino acid in
all organisms
(c)Non-ambiguous – Each codon codes for only one amino
acid
(d)All of the above
40 .Choose the wrong statement in the process of protein
synthesis.
(a)After uncoiling of DNA molecule, one strand acts as a
template for the formation of mRNA
(b)In the presence of DNA polymerase enzyme, the mRNA is
formed based on the triplet codes.
(c)The mRNA that leaves nucleus reaches cytoplasm and
gets attached with 30 S ribosomal subunit
(d)The amino acids are transferred from the intracellular
amino acid pool to the active ribosomes by rRNA.
41 .Match the following columns
Column I Column II
A. UUU 1. Leu
B. UAG 2. Asp
C. AUG 3. Stop
D. GAU 4. Met
E. CUG 5. PheCodes
A B C D E A B C D E
(a) 1 3 2 4 5 (b) 1 2 3 4 5
(c) 5 4 3 2 1 (d) 5 3 4 2 1
42 .In a given segment of mRNA undergoing translation
and the polypeptide synthesised, identify the correct
codes for given amino acids phenylalanine and serine
and sequence of DNA from which this mRNA is
transcribed
I.Sequence of mRNA AUG UUU AUG CCU GUU
UCU UAA
Met—Phe—Met—Pro—Val—Ser→
II.Polypeptide synthesised
(a) TACAAATACGGACAAAAGAATT, UAA and UUA
(b) TTGAAAUCAGGACAAAGAAUU, CAG and AUU
(c) ATGTTTATGCCTGTTTCTTAA UUU and UCU
(d) TACAAATACGGACAAAAGAATT, UUU and UCU
43 .In mRNA, AUG is the initiation codon and UAA, UAG
and UGA are termination codons, therefore
polypeptide cannot be synthesised beyond any of these
triplets to the end of mRNA. Then which one of the
following mRNA can be translated completely.
(a) AUG UUC UCC UGG UAA UAU
(b) AUG UUC UCC UGA UGC UAU
(c) AUC ACG UAU UUC UGA CUC
(d) AUG UAU UUC UGC CUC UAG