Tiêu đề MOLECULAR BASIS OF INHERITANCE.pdf ✅

NEET : Biology [ 136 ] www.allendigital.in  Digital w GENETIC MATERIAL, DNA 1. In eukaryotic cell circular and double stranded DNA occurs in :- (1) Golgibody (2) Mitochondria (3) Nucleus (4) Ribosome 2. Double helix model of DNA which was proposed by Watson and Crick was of:- (1) C-DNA (2) B-DNA (3) D-DNA (4) Z-DNA 3. If there are 10,000 nitrogenous base pairs in a DNA then how many nucleotides are there: (1) 500 (2) 10,000 (3) 20,000 (4) 40,000 4. Double helix model of DNA was proposed by : (1) Watson and Crick (2) Schleiden schwann (3) Singer and Nicholson (4) Kornberg and Khurana 5. Back bone in structure of DNA molecule is made up of :- (1) Pentose Sugar and phosphate (2) Hexose sugar and phosphate (3) Purine and pyrimidine (4) Sugar and phosphate 6. Substance common in DNA and RNA :- (1) Hexose Sugar (2) Histamine (3) Thymine (4) Phosphate groups 7. Nucleotide is :- (1) N2 - base, pentose sugar and phosphoric acid (2) Nitrogen, Hexose sugar and phosphoric acid (3) Nitrogen base, pentose sugar (4) Nitrogen base, trioses and phosphoric acid 8. Unit of nucleic acids are:- (1) Phosphoric acid (2) Nitrogenous bases (3) Pentose Sugar (4) Nucleotides 9. Which element is not found in nitrogenous base ? (1) Nitrogen (2) Hydrogen (3) Carbon (4) Phosphorus 10. DNA was first discovered by:- (1) Meischer (2) Robert Brown (3) Flemming (4) Watson & Crick 11. Nucleic acid (DNA) is not found in:- (1) Nucleus & nucleolus (2) Peroxysome & ribosome (3) Mitochondria & plastid (4) Chloroplast & nucleosome 12. DNA is not present in :- (1) Mitochondria (2) Chloroplast (3) Bacteriophage (4) TMV 13. A nucleic acid contains thymine or methylated uracil then it should be :- (1) DNA (2) RNA (3) Either DNA or RNA (4) RNA of bacteria 14. Prokaryotic genetic system contains :- (1) DNA & histones (2) RNA & histones (3) Either DNA or histones (4) DNA but no histones 15. A N2 - base together with pentose sugar and phosphate forms (or) building - block unit of nucleic acid is :- (1) Nucleoside (2) Polypeptide (3) Nucleotide (4) Amino acid 16. Which of the following is not a pyrimidine N2 base ? (1) Thymine (2) Cytosine (3) Guanine (4) Uracil 17. The purine & pyrimidine pairs of complementary strands of DNA are held together by :– (1) H - bonds (2) O - bonds (3) C - bonds (4) N - bonds 18. Number of H - bonds between guanine and cytosine are :- (1) One (2) Two (3) Three (4) Four Exercise-I
Molecular Basis of Inheritance  Digital www.allendigital.in [ 137 ] 19. Which purine & pyrimidine bases are paired together by H - bonds in DNA ? (1) AC & GT (2) GC & AT (3) GA & TC (4) None of the above 20. A single stranded DNA is present in:- (1) TMV (2) Salmonella (3)  x 174 (4) Bacteria 21. What is the nature of the 2 strands of a DNA duplex ? (1) Identical & Complimentary (2) Antiparallel & complimentary (3) Dissimilar & non complimentary (4) Antiparallel & non complimentary 22. On an average, how many purine N2 bases are present in single coil of DNA :- (1) Four (2) Five (3) Ten (4) Uncertain 23. Distance between two nucleotide pairs of DNA is :- (1) 0.34 nm (2) 34 Å (3) 3.4  (4) 34 nm 24. In a double strand DNA amount of Guanine is 35% then what will be the amount of cytosine:- (1) 70% (2) 15% (3) 30% (4) 35% 25. Chargaaf 's rule is given as :- (1) Purines  Pyrimidines (2) A + G = T+ C (3) A+ U = G + C (4) A + T / G + C = Const. 26. In RNA , Nucleotides are bonded by :- (1) H - bonds (2) Phospo diester bonds (3) Ionic bonds (4) Salt linkage 27. A nucleoside differs from a nucleotide is not having :- (1) Phosphate (2) Sugar (3) Phosphate & sugar (4) Nitrogen base 28. Wilkins X-ray diffraction showed the diameter of the DNA helix is :- (1) 10 Å (2) 20 Å (3) 30 Å (4) 40 Å 29. In the DNA of an animal percentage of Adenine is 30 then percentage of Guanine will be :- (1) 40 (2) 30 (3) 20 (4) 70 30. Length of one loop of B- DNA:- (1) 3.4 nm. (2) 0.34 nm. (3) 20 nm. (4) 10 nm. 31. If base order in one chain of DNA is "ATCGA" then how many no. of H–bond found in DNA duplex :– (1) 20 (2) 12 (3) 10 (4) 11 32. In DNA purine nitrogen bases are :- (1) Uracil and Guanine (2) Guanine and Adenine (3) Adenine and cytosine (4) None 33. Two free ribonucleotide units are interlinked with :- (1) Peptide bond (2) Disulphide bond (3) Hydrogen bond (4) Phosphodiester bond 34. Short DNA segment has 80 thymine and 90 guanine bases. The total number of nucleotides are :- (1) 160 (2) 40 (3) 80 (4) 340 35. Prokaryotic DNA is :- (1) double stranded circular (2) single stranded circular (3) double stranded linear (4) double stranded RNA as nucleic acid 36. Nucleoside is :- (1) Polymer of nucleic acid (2) Phosphoric acid + base (3) Phosphoric acid + sugar + base (4) Sugar + base 37. The back bone of RNA is consists of which of the following sugar ? (1) Deoxyribose (2) Ribose (3) Sucrose (4) Maltose
NEET : Biology [ 138 ] www.allendigital.in  Digital 38. In a nucleotide H3PO4 binds to which carbon atom of pentose sugar? (1) Only 1st carbon (2) Only 3rd carbon (3) Only 5th carbon (4) Both 3rd and 5th carbon 39. DNA is acidic due to:- (1) Sugar (2) Phosphoric acid (3) Purine (4) Pyrimidine 40. RNA contains which of the following base, in place of Thymine of DNA ? (1) Thymine (2) Uracil (3) Adenine (4) None of these 41. Genetic information are transferred from nucleus to cytoplasm of cell through :- (1) DNA (2) RNA (3) Lysosomes (4) ACTH 42. If one strand of double stranded DNA, consists of the sequence 3'–ATTCGTAC–5', then the complementary sequence must be:– (1) 5'–UAAGCAUG–3' (2) 3'–TAAGCATG–5' (3) 5'–TAAGCATG–3' (4) 5'–TAAGCATG–3' in the reverse direction 43. DNA molecule has uniform diameter due to:- (1) Double stranded (2) Presence of phosphate (3) Specific base pairing between purine and pyrimidine (4) Specific base pairing between purine and purine 44. Following structure is related to which compound? (1) Adenine (2) Guanine (3) Uracil (4) Thymine 45. If the sequence of bases in one strand of DNA is known then the sequence in other strand can be predicted on the basis of: – (1) Antiparallel (2) Complementary (3) Polarity (4) Coiling 46. The unequivocal proof that DNA is the genetic material came from the experiments of :– (1) Hershey and Chaese (1952) (2) Frederik Griffith (1928) (3) Watson and Crick (4) Meselson and Stal (1958) DNA REPLICATION 47. In process of replication deoxyribonucleoside triphosphate:- (1) acting as substrate (2) providing energy for polymerisation reaction (3) acting as an enzyme (4) both (1) and (2) 48. DNA Replication occurs at :- (1) G0 & G1 (2) G2 - stage (3) S – Stage (4) Mitotic phase 49. A DNA molecule in which both strands have radioactive thymidine is allowed to duplicate in an environment containing non- radioactive thymidine. What will be the exact number of DNA molecules that contains the radio active thymidine after 3 duplications ? (1) One (2) Two (3) Four (4) Eight 50. A bacterium with completely radioactive DNA was allowed to replicate in a non- radioactive medium for two generation what % of the bacteria should contain radioactive DNA ? (1) 100 % (2) 50 % (3) 25 % (4) 12.5 % 51. In the base sequence of one strand of DNA is GAT, TAG, CAT, GAC what shall be the sequence of its complementary strand? (1) CAT, CTG, ATC, GTA (2) GTA, ATC, CTG, GTA (3) ATC, GTA, CTG, GTA (4) CTA, ATC, GTA, CTG
Molecular Basis of Inheritance  Digital www.allendigital.in [ 139 ] 52. Method of DNA replication in which two strands of DNA separates and synthesize new strands? (1) Dispersive (2) Conservative (3) Semiconservative (4) Non conservative 53. During replication of a bacterial chromosome DNA synthesis starts from a replication origin site and :- (1) RNA primers are not involved (2) is facilitated by telomerase (3) moves in one direction of the site (4) moves in bi-directional way 54. The nature of DNA replication is :- (1) Conservation (2) Non conservative (3) Semi-conservative (4) Cyanobacteria 55. The direction of DNA replication is :- (1) From 5' end towards 3' end (2) From 3' end towards 5' end (3) Amino terminus to carboxy terminus (4) Carboxy terminus to amino terminus 56. Semiconservation replication of DNA was proposed by :- (1) Watson and Crick (2) Bateson and Punnett (3) Messelson and Stahl (4) Avery, McCarty and Mactleod 57. Which of the following enzyme is used in DNA multiplication ? (1) RNA polymerase (2) DNA endonuclease (3) Exonuclease (4) DNA Polymerase 58. Mode of DNA replication in E. coli is :- (1) Conservative and unidirectional (2) Semi conservative and unidirectional (3) conservative and bidirectional (4) Semi conservative and bidirectional 59. Which of the following enzyme is used to join DNA fragments? (1) Terminase (2) Endonuclease (3) Ligase (4) DNA polymerase 60. Okazaki fragments are synthesised on :- (1) Leading strands of DNA only (2) Lagging strands of DNA only (3) Both leading and lagging strands of DNA (4) Complementary DNA 61. DNA replication includes :- (1) DNA ligase (2) DNA polymerase and ligase (3) RNA polymerase and ligase (4) All of these 62. In DNA replication, the primer is :- (1) A small deoxyribonucleotide polymer (2) A small ribonucleotide polymer (3) Helix destabilizing protein (4) Enzyme taking part in joining nucleotides of new strand 63. The strand of DNA, which does not code for anything is referred to as :- (1) Template strand (2) Antisense strand (3) Coding strand (4) Noncoding strand 64. During DNA replication discontinuously synthesized fragments are later joined by the enzyme :– (1) Ligase (2) DNA polymerage (3) RNA primer (4) Primase 65. Replication fork is :– (1) Large opening of the DNA helix (2) Small opening of the DNA helix (3) Tightly coiled part of DNA helix (4) Loosely coiled part of DNA helix 66. The DNA dependent DNA polymerase catalyse polymerisation in:– (1) 3' → 5' direction (2) 5' → 3' direction (3) Depend on the nature of template strand (4) both (1) and (2) 67. Main enzyme of DNA replication is :– (1) DNA dependent RNA polymerase (2) DNA dependent DNA polymerase (3) RNA dependent RNA polymerase (4) RNA dependent DNA polymerase