Ncert-Class12- Biology- Molecular Basis of inheritance Welcome to your Ncert-Class12- Biology- Molecular Basis of inheritanceInstructionTotal Questions : 20Total Marks : 20 x 4 = 80 MarksEach Correct Question carries : 4 MarksEach incorrect Question Carries : -1 MarksEach Unattempted Question carry : 0 MarksBe careful On Negative Markings During autocatalysis of DNA, which one of the following provide free OH group and is also used to anchor for addition of new DNA nucleotides? DNA polymerase Ligase RNA primer Topoisomerase None Analysis of DNA of an organism revealed the following characters. Mark the option that is not likely to be true if the organism is a cat. The double helix is antiparallel & a linear molecule 20 bases comprising of a mixture of deoxyribonucleotide phosphates (dNTPs) were found in a single 360 degree turn of helix 17 % of the nitrogenous bases were shown to be cysteines Uracil was lacking but guanine was 17 % None Choose the correct answer from the alternatives given :Watson and Crick (1953) proposed DNA double helix model and won the Nobel Prize; their model of DNA was based on(i) X-ray diffraction studies of DNA done by Wilkins and Franklin(ii) Chargaffs base equivalence rule(iii) Griffiths transformation experiment(iv) Meselson and Stahls experiment. (i), (ii) and (iv) (i) and (ii) (iii) and (iv) (i), (ii), (iii) and (iv) None Choose the correct answer from the alternatives given :Which of the following phenomena was experimentally proved by Meselson and Stahl? Transformation Transduction Semi-conservative DNA replication Central dogma None Choose the correct answer from the alternatives given :Read the following statements.(i) One codon codes for only one amino acid.(ii) Some amino acids are coded by more than one codon.(iii) The, sequence of triplet nitrogenous bases in DNA or mRNA corresponds to the amino acid sequence in the polypeptide chain.Give suitable terms for the characteristics of genetic code as per the above statements. Degeneracy - (i), Colinearity - (ii), Unambiguous - (iii) Degeneracy - (iii) , Colinearity - (ii) , Unambiguous - (i) Degeneracy - (ii) , Colinearity - (iii) , Unambiguous - (i) Degeneracy - (i) , Colinearity (ii) , Unambiguous - (iii) None What is the relationship between the nucleotide triplets and the amino acids called? Genetic code Transcription Translation Replication None Which of the following statements about DNA replication is not correct? Unwinding of the DNA molecule occurs as hydrogen bonds break Replication occurs as each base is paired with another exactly like it Process is known as semiconservative replication because one old strand is conserved in the new molecule Complementary base pairs are held together with hydrogen bonds None A naturally occurring coding strand composed of alternating C and U residues would result in the formation of A polypeptide containing alternating leu and ser residues A polypeptide containing either leu or ser residues A polypeptide containing only leu residues A polypeptide containing only ser residues None The double helical model of the DNA was proposed by Watson and Crick based on that what data produced by Wilkins and Franklin? Hybridization DNA sequencing Southern blotting X-ray diffraction None Which one of the following is correct? Introns are present in mRNA and exons are present in tRNA. Codons are present in mRNA and anticodons in tRNA. Every intron is a set of three terminator codons. Exons are present in eukaryotes while introns are present in prokaryotes. None Identify the correct and incorrect statements.A. The four nucleotide bases are not necessarily present in DNA in exact equal proportions.B. The total amount of purines are equal to the total amount of pyrimidines.C. DNA ligase enzyme act to hydrolyse or breakdown a polynucleotide chain into its component nucleotides.D. Nuclease enzymes are capable of restoring an intact DNA duplex. B is correct but A, C and D are wrong. A and B are wrong but C and D are correct. A, B and C are correct but D is wrong. A and B are correct but C and D are wrong. None The base sequence for a nucleic acid segment is given CAG, AGG, CGA, CCA. From this, it can definitely be concluded that it is a segment of which strand? DNA strand mRNA strand tRNA strand Data not sufficient None In prokaryotes, the process of replication is catalysed by the following enzymes. Identify which of the enzymes is best coordinated with the role? Helicase → → Joins the ends of DNA segments DNA polymerase I → → Synthesis of DNA DNA polymerase II → → Erases primer and fills gaps Primase → → Synthesis RNA primers4 None The characteristics of a molecular probe are(I) Very long molecule(II) Double stranded(III) DNA or RNA(IV) Complementary to a part of desired geneThe correct options are I, II II, III III, IV IV, I None A DNA molecule in which both strand have radioactive thymidine is allowed to duplicate in an environment containing non-radioactive thymidine. What will be the correct number of DNA molecules that contain some radioactive thymidine after three duplications? There will be four such molecules. There will be eight such molecules. There will be only one such molecule. There will be two such molecules. None What is antisense technology? When a piece of RNA that is complementary in sequence is used to stop expression of a specific gene RNA polymerase producing DNA A cell displaying a foreign antigen used for synthesis of antigens Production of somaclonal variants in tissue cultures None The sequencing of the entire genome (the totality of all genes) of an organism was completed in 1996. The organism was Human being Yeast Albino mouse Plasmodium vivax None Choose the correct answer from the alternatives given :In a DNA strand the nucleotides are linked together by Glycosidic bonds Phosphodiester bonds Peptide bonds Hydrogen bonds None Which of the following biologists has been dubbed as the architect of molecular biology? Francis Crick Frederick Sanger Jacques Lucien Monod James Watson None The toxin produced by the bacteria that is responsible for the development of diarrhea is produced by a section of DNA that has the code CCT TAT CAG. The sequence of amino acids produced by this sequence is ____________. Glycine - isoleucine - aspartic acid Glycine - isoleucine - valine Glycine - tyrosine - valine Glycine - tyrosine - isoleucine None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
