NEET Biology Molecular Basis of Inheritance MCQs Set 03

Question: Haploid content of human DNA contains

• a) 3.3 × 10⁹ bp
• b) 6.6 × 10⁹ bp
• c) 3.3 × 10⁸ bp
• d) 4.6 × 10⁶ bp

Answer: 3.3 × 10⁹ bp

Question: Which of the following nitrogenous bases are common for both RNA and DNA?

• a) C, G, A
• b) G, A, U
• c) T, A, C
• d) U, A, C

Answer: C, G, A

Question: Adjacent nucleotides in a polynucleotide chain are joined by

• a) Phosphodiester bond
• b) O-glycosidic bond
• c) Hydrogen bond
• d) N-glycosidic bond

Answer: Phosphodiester bond

Question: Sugars are attached to the pyrimidines by the formation of

• a) N-glycosidic bond
• b) Phosphoester bond
• c) O-glycosidic bond
• d) Hydrogen bond

Answer: N-glycosidic bond

Question: Cytidine is a

• a) Nucleoside
• b) Nucleotide
• c) Nitrogen base
• d) Common dinucleotide in DNA and RNA

Answer:  Nucleoside

Question: Which of the following process is related to reverse transcription?

• a) RNA dependent DNA synthesis
• b) RNA dependent polypeptide synthesis
• c) DNA dependent DNA synthesis
• d) DNA dependent RNA synthesis

Answer: RNA dependent DNA synthesis

Question: Which of the following structures are present in core particle of nucleosome?

• a) Octamer of histone proteins
• b) Non-histone proteins
• c) 200 bp of DNA
• d) Linker DNA

Answer: Octamer of histone proteins

Question: Packaging of DNA helix

• a) Is more complex in eukaryotes than prokaryotes
• b) Requires acidic proteins that help in coiling of DNA in prokaryotes
• c) Occurs with the help of NHC proteins only
• d) Involves polyamines in eukaryotes

Answer:  Is more complex in eukaryotes than prokaryotes

Question: Length of DNA in E. coli is

• a) 1.36 mm
• b) 1.36 m
• c) 3.4 m
• d) 2.2 m

Answer: 1.36 mm

Question: Dominance of RNA world is proved by

• a) Splicing
• b) Polyadenylation
• c) All of these
• d) Capping

Answer: Splicing

Question: Which plant was used by Taylor to prove semiconservative replication at chromosomal level?

• a) Vicia faba
• b) Trillium
• c) Ophioglossum
• d) Haematoxylon

Answer: Vicia faba

Question: Unwinding of DNA creates tension which is released by enzyme

• a) Topoisomerase
• b) Primase
• c) Ligase
• d) Helicase

Answer: Topoisomerase

Question: During polymerisation of deoxyribonucleosides triphosphates in bacteria which of the following enzyme is mainly required?

• a) DNA dependent DNA polymerase
• b) DNA gyrase
• c) DNA dependent RNA polymerase
• d) RNA dependent DNA polymerase

Answer: DNA dependent DNA polymerase

Question: During DNA replication which of the following does not act as substrates?

• a) dUTP
• b) dGTP
• c) dCTP
• d) dATP

Answer: dUTP

Question: Out of the two strands of DNA one is carrying genetic information for transcription and it is called

• a) Template strand
• b) Sense strand
• c) Non template strand
• d) Coding strand

Answer:  Template strand

Question: When a mature mRNA was hybridised to its gene certain loops were observed. These loops represent

• a) Introns in DNA
• b) Introns in rRNA
• c) Exons in DNA
• d) Exons in tRNA

Answer: Introns in DNA

Question: Poly A tail is present in

• a) mRNA of eukaryotes
• b) Promotor of bacteria
• c) tRNA of eukaryotes
• d) mRNA of bacteria

Answer:  mRNA of eukaryotes

Question: Find out the incorrect match

• a) UAG – Sense codon
• b) UGG – Tryptophan
• c) UUU – Phenylalanine
• d) GUG – Valine

Answer: UAG – Sense codon

Question: One codon codes for only one amino acid, hence the code is

• a) Unambiguous and specific
• b) Unambiguous and non-specific
• c) Ambiguous and non-specific
• d) Ambiguous and specific

Answer: Unambiguous and specific

Question: What is incorrect for UTR?

• a) Present in between the translational unit in mRNA
• b) Required for efficient translation process
• c) Not recognised by any tRNA
• d) Provide stability to mRNA

Answer:  Present in between the translational unit in mRNA

Question: In bacteria, catalytic RNA is found in

• a) 50S subunit of ribosome
• b) 40S subunit of ribosome
• c) 60S subunit of ribosome
• d) 30S subunit of ribosome

Answer: 50S subunit of ribosome

Question: In lac operon, the regulator gene codes for

• a) Active repressor
• b) Inactive repressor
• c) Corepressor
• d) Aporepressor

Answer: Active repressor

Question: Mark the incorrect option w.r.t. lac operon

• a) Shows feed back repression
• b) Is under positive as well as negative control
• c) Controls catabolic pathway
• d) Discovered by Jacob and Monod

Answer: Shows feed back repression

Question: In lac operon, the lac mRNA

• a) Has several initiation and termination codons
• b) Is not transcribed in the presence of lactose
• c) Forms four different enzymes
• d) Is involved in an anabolic reaction

Answer:  Has several initiation and termination codons

Question:  How many locations have been identified in human genome where single base differences occur?

• a) 1.4 million
• b) 14 million
• c) 1.4 billion
• d) 14 billion

Answer: 1.4 million

Question: The non-human model organisms sequenced in Human Genome project were

• a) A nematode and fruit fly
• b) Fish and birds
• c) Wheat and rice
• d) Garden pea and fruit fly

Answer: A nematode and fruit fly

Question: Mark the correct one (w.r.t. application of DNA fingerprinting)

• a) More than one option is correct
• b) Determining the population diversity
• c) Forensic science
• d) Determining the genetic diversity

Answer: More than one option is correct

Question: What is incorrect for human chromosome 1?

• a) Its sequence was completed in May 2007
• b) It was the last chromosome to be sequenced
• c) It is one of the largest chromosome
• d) It has maximum number of genes

Answer:  Its sequence was completed in May 2007

Question: In the technique of DNA fingerprinting digestion of DNA is followed by

• a) Electrophoresis
• b) Hybridisation
• c) Denaturation
• d) Southern blotting

Answer: Electrophoresis

Question: In eukaryotes, RNA polymerase III catalyses the synthesis of

• a) 5 S rRNA, tRNA & SnRNA
• b) 28 S rRNA, 18 S rRNA & 5 S rRNA
• c) All types of rRNA & tRNA
• d) 28 S rRNA, 18 S rRNA & 5 S rRNA

Answer: 5 S rRNA, tRNA & SnRNA

Question:  Read the following statements:

A. Variation at genetic level arises due to mutations.
B. Technique of DNA fingerprinting was initially developed by Alec Jeffreys

• a) Both (A) and (B) are correct
• b) Both (A) and (B) are incorrect
• c) Only (B) is correct
• d) Only (A) is correct

Answer: Both (A) and (B) are correct

Question: In DNA fingerprinting, detection of hybridised DNA fragments is possible by

• a) Autoradiography
• b) Centrifugation
• c) Blotting
• d) Electrophoresis

Answer: Autoradiography

Question: Mark the correct match

• a) VNTR – Intron
• b) Sanger method – Determination of amino acid sequences in proteins only
• c) Val operon – Found in eukaryotes
• d) None of these

Answer:   VNTR – Intron

Question: NHC structural proteins are

• a) Required for packaging of chromatin at higher levels
• b) Catalytic proteins rich in tryptophan and arginine
• c) Regulatory proteins
• d) Basic proteins rich in lysine, arginine

Answer: Required for packaging of chromatin at higher levels

Question: How many types of DNA polymerases are present in bacteria?

• a) Three
• b) Two
• c) One
• d) Five

Answer: Three

Question: Synthesis of leading and lagging strand require

• a) Single and many primers respectively
• b) Many primers
• c) Single primer
• d) Many and single primers respectively

Answer: Single and many primers respectively

Question: For the strand separation and stabilisation during DNA replication which of the following set of enzymes and proteins are required?

• a) Topoisomerase, helicase, SSBP
• b) Topoisomerase, helicase, ligase
• c) SSBP, gyrase, primase
• d)  SSBP, gyrase, primase

Answer: Topoisomerase, helicase, SSBP

Question: In eukaryotes, the RNA polymerase that synthesises tRNA is RNA polymerase ______ and is also responsible for formation of ______ rRNA.

• a) III, 5 S
• b) II, 18 S
• c) I, 5 S
• d) II, 5.8 S

Answer: III, 5 S

Question: What is correct for bacterial transcription?

• a) Transcription and translation takes place in the same compartment
• b) Translation can begin when mRNA is fully transcribed
• c) mRNA requires processing to become active
• d) Rho factor initiates the process

Answer:  Transcription and translation takes place in the same compartment

Question: Which of the following is not required during post transcriptional processing in eukaryotes?

• a) ScRNA
• b) Methyl guanosine triphosphate
• c)  Ligase
• d) SnRNA

Answer: ScRNA

Question: Which of the following feature is correct for bacteria?

• a) DNA can be chromosomal as well as extrachromosomal
• b) Linear ss-DNA representing single chromosome
• c) DNA does not show coiling
• d) Presence of intervening sequences in DNA

Answer: DNA can be chromosomal as well as extrachromosomal

Question: In-vitro template independent RNA synthesis is a feature of

• a) Ochoa enzyme
• b) DNA polymerase
• c) Reverse transcriptase
• d) RNA polymerase

Answer: Ochoa enzyme

Question: In protein synthesis, which of the following are required for the synthesis of charged tRNA?

• a) Amino acid, ATP, Mg⁺⁺, enzyme, tRNA
• b) Amino acid, GTP, initiation codon, ribosome
• c) Amino acid, ATP, K⁺, enzyme, mRNA
• d) Aminoacyl tRNA, ribosome, initiation codon, release factor

Answer: Amino acid, ATP, Mg⁺⁺, enzyme, tRNA

Question: Termination of polypeptide synthesis in bacteria differs from eukaryotes in

• a) Involving more than one type of release factors
• b) Having different termination codons
• c) Being GTP dependent
• d) All of these

Answer: Involving more than one type of release factors

Question: The accessibility of promoter regions of bacterial DNA in many cases regulated by the interaction of proteins with sequences termed

• a) Operators
• b) Inhibitor genes
• c) Structural genes
• d) Regulators

Answer: Operators

Question: When the genomes of two people are cut using the same restriction enzyme, the length and number of fragments obtained are different, this is called

• a) RFLP
• b) PCR
• c) EST
• d) Northern blotting

Answer:  RFLP

Question: Which of the following does not code for any proteins?

• a) More than one option is correct
• b) Mini-satellites
• c) Exons
• d) Micro-satellites

Answer: More than one option is correct

Question: Which statement is correct for homeotic genes?

• a) Control is exerted through homeodomain proteins
• b) Mutation in these genes not results in conversion of one body part into another
• c) Such genes have been studied extensively in humans
• d) Control oncogenesis process

Answer: Control is exerted through homeodomain proteins

Question: In which step of DNA profiling, nitrocellulose membrane is used?

• a) Blotting
• b) DNA amplification
• c) Autoradiography
• d) Denaturation

Answer:  Blotting

Question: Repressor of lac-operon

• a) Is a tetrameric protein
• b) Has only one side
• c) Having a molecular weight of 16,000
• d) Is made by operator gene

Answer: Is a tetrameric protein

Question: Select the correct one (w.r.t. Wobble hypothesis)

• a) Third base can establish H-bonds even with the non complementary anticodon
• b) Third base of a codon lacks vibrating capacity
• c) Specificity of a anticodon is particularly determined by first two codon
• d) Major cause of degeneracy is the first two N-bases of codon

Answer: Third base can establish H-bonds even with the non complementary anticodon

Question: A set of genes or cDNA is immobilized on a glass slide and used in transcriptome studies is called

• a) Microarray
• b) DNA chip
• c) Genome
• d) Proteome

Answer: Microarray

Question: If there are 81 million bases in RNA of human cell, then calculate the total number of introns present in cDNA

• a) Zero
• b) Half the number of ribonucleotides
• c)  Equal to ribonucleotides
• d) 27 millions

Answer: Zero

Question: Splicing is necessary for preparing a mature transcript and its movement to cytoplasm. It requires

• a) snRNA and proteins
• b) scRNA and snRNA
• c) scRNA only
• d) scRNA and proteins

Answer:  snRNA and proteins