MCQ Molecular Basis of Inheritance for ISC Class 12 Biology
MCQ Type Question for ISC Class 12 Biology Molecular Basis of Inheritance
|Molecular Basis of Inheritance|
|Syllabus||on bifurcated syllabus (after reduction)|
|Topic||MCQ / Objective Type Question|
ISC Class-12 Biology MCQ Molecular Basis of Inheritance
Question 1: Initiation codon of protein synthesis (in eukaryotes) is
Answer: (d) AUG
Question 2: In eukaryotes, mRNA is synthesized with the aid of
(a) RNA polymerase III.
(b) RNA polmerase II.
(c) RNA polymerase I.
(d) reverse transcriptase.
Answer: (b) RNA polmerase II.
Question 3: Lactose operon produces enzymes
(a) b-galactosidase, permease and glycogen synthetase.
(b) b-galactosidase, permease and transacetylase.
(c) permease, glycogen synthetase and transacetylase.
(d) b-galactosidase, permease and phosphoglucose isomerase.
Answer: (b) b-galactosidase, permease and transacetylase.
Question 4: In Hershey and Chase experiments, radioactive 32P was used to culture bacteriophages which resulted in radioactive
Question 5: Commonly used vectors for human genome sequencing are:
Answer: (b) BAC and YAC
Question 6: Nucleic acids are polymer of
Answer: (d) Nucleotides
Question 7: DNA structure was discovered by
(b) Watson and Crick
(c) Har Gobind Khorana
Answer: (b) Watson and Crick
Question 8: Enzyme responsible for DNA replication\
Answer: (a) Polymerase
Question 9: In a DNA strand the nucleotides are linked together by
(a) glycosidic bonds
(b) phosphodiester bonds
(c) peptide bonds
(d) hydorgen bonds.
Answer: (b) phosphodiester bonds
Question 10: The net electric charge on DNA and histones is
(a) both positive
(b) both negative
(c) negative and positive, respectively
Answer: (c) negative and positive, respectively
Question 11: The human chromosome with the highest and least number of genes in them are respectively
(a) chromosome 21 and Y
(b) chromosome 1 and X
(c) chromosome 1 and Y
(d) chromosome X and Y.
Answer: (c) chromosome 1 and Y
Question 12: Who amongst the following scientist had no contribution in the development of the double helix model for the structure of DN A ?
(a) Rosalind Franklin
(b) Maurice Wilkins
(c) Erwin Chargaff
(d) Meselson and Stahl
Answer: (b) Maurice Wilkins
Question 13: Represser Lac-Operon protein attached to:
(d) β-Glacto sidase
Answer: (b) Inducer
Question 14: Following is important in Ïranscription:
(a) DNA Methylase
(b) CAAT Box
(d) DNA Polymerase
Answer: (d) DNA Polymerase
Question 15: In eukaryotes which of the following is removed from initially transcribed RNA before it is transported to the cytoplasm for translation ?
(b) 3′ Poly A tail
(c) Ribosome binding site
(d) 5′ cap
Answer: (a) Intron
Question 16: The process of splicing in eukaryotes :
(a) is reminiscent of antiquity
(b) represents dominance of RNA world
(c) is an indicator of the complexity of human genome
(d) is a legacy of organic evolution
Answer: (b) represents dominance of RNA world
Question 17: Cistron is
(a) Functional unit of RNA
(b) Non-functional unit of RNA
(c) Functional unit of DNa that specifies a polypeptide chain
(d) Non-functional unit of DNA
Answer: (c) Functional unit of DNa that specifies a polypeptide chain
Question 18: Transcription is the formation of
Answer: (a) mRNA
Question 19: The RNA polymerase holoenzyme transcribes:
(a) the structural gene and the terminator regions
(b) the structural gene only
(c) the promoter, and the
(d) the promoter, structural gene and the terminator region
Answer: (a) the structural gene and the terminator regions
Question 20: If the base sequence of a codon in mRNA is 5′-AUG-3′, the sequence of tRNA pairing with it must be
(a) 5′ – CAU – 3′
(b) 5′ – AUG – 3′
(c) 5′ – GUA – 3′
(d) 5′ – UAC – 3′
Answer: (a) 5′ – CAU – 3′
Question 21: The amino acid attaches to the tRNA at its:
(a) 3′ – end
(b) 5′ – end
(c) Anti codon site
(d) DHU loop
Answer: (a) 3′ – end
Question 22: To initiate translation, the mRNA first binds to
(a) The smaller ribosomal sub-unit
(b) The larger ribosomal sub-unit
(c) The whole ribosome
(d) No such specificity exists
Answer: (a) The smaller ribosomal sub-unit
Question 23: Which of the following steps in transcription is catalysed by RNA polymerase ?
(d) All of the above
Answer: (d) All of the above
Question 24: Control of gene expression takes place at the level of
(d) none of the above.
Answer: (b) transcription
Question 25: If the sequence of initrogen bases of the coding strand of DNA in a transcription unit is: 5’ – ATGAATG – 3’, the sequence of bases in its RNA transcript would be
(a) 5’ – AUG A AUG – 3’
(b) 5’ – UACUU AC – 3’
(c) 5’ – CAUUCAU – 3’
(d) 5’ – GUAAGUA – 3’.
Answer: (d) 5’ – GUAAGUA – 3’.
Question 26: The RNA polymerase holocnzyme transcribes
(a) the promoter, structural gene and the terminator region.
(b) the promoter and the terminator region
(c) the structural gene and the terminator region
(d) the structural gene only.
Answer: (b) the promoter and the terminator region
Question 27: The amino acid attaches to the tRNA at its
(a) 5’- end
(b) 3’ – end
(c) anticodon site
Answer: (b) 3’ – end
Question 28: To initiate translation, the wiRNA first bind to
(a) the smaller ribosomal sub-unit
(b) the larger ribosomal sub-unit
(c) the whole ribosome
(d) no such specificity exists.
Answer: (a) the smaller ribosomal sub-unit
Question 29: In DNA helix:
(a) Quadrate structure
(c) Antiparallel Polarity
(d) Disuiphide bond
Answer: (c) Antiparallel Polarity
Question 30: During splicing axon attached and inducer enzyme for reaction:
(a) RNA Ligase
(b) RNA Catalase
(c) RNA permease
(d) RNA poloymerase
Answer: (b) RNA Catalase
Question 31: In prokaryotes, the predominant site for control of gene expression is the :
(a) transcription initiation
(b) processing level