BIO202 Final Term Past Papers by Arham

OBJECTIVEs

1. The Tm of DNA is influenced by _______ All Of Above
2. Purine base found in RNA is_________ Guanine
3. Compounds that generate nitrous acid (such as nitrites, nitrates, and nitrosamines) change DNA molecules by: _____ _____ Breakage Of Phosphodiester Bonds
4. Under appropriate conditions DNA will form a hybrid with a complementary ____ Both
5. DNA model was presented by Watson and Crick in _________1953
6. Around structural core of the nucleosome. a segment of the DNA double helix is wound nearly twice - approximately _______ 140bp
7. Adenosine 3'-phosphate-5'-phosphosulfate is the ---------------- donor_____ Sulphate
8. A short length of DNA molecule has 80 thymine and 80 guanine bases. The total number of nucleotide in the DNA fragment is _______ 320
9. Which of the following is a palindromic sequence? GGATCC CCTAGG
10. The complex folding of large chromosomes within eukaryotic chromatin and bacterial nucleoids is generally considered ____ Tertiary Structure
11. Higher GC base pairs increases Tm, because , with three hydrogen bonds, require-…. heat energy to dissociate than AT base pairs. ___ __ More
12. Chromatin is composed of _____ Nucleic Acids And Protein
13. The sugar molecule present in nucleotide is_____ Pentose
14. Eukaryotic DNA is associated with tightly bound basic …. called histones ___ Proteins
15. When DNA is heated, the temperature at which ------ of the helical structure is lost is defined as the melting temperature ______One Half
16. Z-DNA have a _______Zig-Zag Appearance
17. RNA duplexes are -…. stable than DNA duplexes _____ More
18. The ……. strand is called Template strand while____3-5
19. DNA replication is ______ Semi-Conservative
20. Nucleotides are composed of ___ All
21. Glucose residues in amylose are linked by ____. α (1,4) linkage
22. The number of carbon atoms in lysine is ____. 6
23. If the carbonyl group is present at the end of the monosaccharide, then it is called __ Aldose
24. The number of stereoisomers for a molecule containing only one chiral carbon is ___ 2
25. Seminal fluid is rich in ___. Fructose
26. Which of the following glycosidic linkage exists between two glucose units of maltose? ___Alpha 1,4
27. Amino sugar is formed by the replacement of the hydroxyl group at ----- of the parent monosaccharide with amino group. _____ C-2
28. Which one of the following is a structural homopolysaccharide? _____Cellulose
29. Which one of the following amino acids is not specified by three letter codons? Selenocysteine
30. Acid dissociation constants are designated as _______. PKa
31. 42. When linked to vitamins nucleotides are structural components of several essential coenzymes. For ______Coenzyme A Spring 2023
32. The "energy carrier" ATP is an example of a(n): ____Deoxyribonucleoside Triphosphate
33. The - strand is called Template strand while ______ 3-5
34. Nucleotides also serve as carriers of activated intermediates in the synthesis of ---- All
35. These bonds, plus the van der Waals and hydrophobic interactions between the adjacent stacked bases, stabilize the structure of the double helix ____ Hydrogen
36. Histones are ---- charged __ Positively
37. A phosphodiester r bond is present in _____ Nucleic Acids In A Nucleotide
38. Which one of the following is true of the pentoses found in nucleic acids? ___The Pentoses Are Always

In The Bita-Furanose Forms

39. A DNA segment contains 100 Adenine and 100 cytosines, how many nucleotides are present in the segment? _____400
40. The DNA oligonucleotide abbreviated pATCGAC: ___ Has A Hydroxyl At Its 3 Ends
41. In living cells, nucleotides and their derivatives can serve as: ____All Of The Above
42. S-adenosylmethionine is a …. group donor ___ Methyl
43. Which one is example of coenzymes ____All
44. ATP is _______Nucleotide
45. There are ~ classes of histones ___5
46. Single-stranded DNA has … relative absorbance at 260nm wavelength than does double- stranded DNA ___ Higher
47. Separation of the two strands of the double helix when …… bonds between the paired bases are disrupted

_ Hydrogen

48. Find the correct statement about phosphodiester linkage between adjacent nucleotides in nucleic

acids______5'-Phosphate Of One Nucleotide Joins The 3- Hydroxyl Of The Next Nucleotide

49. According to Chargaff's Rules which one is not correct __ Guanine Equals The Amount Of Thymine
50. Nucleosomes can be packed more tightly to form polynucleosome also called a nucleofilament or a --- -nm fibre. __30
51. Nucleoside contains_____ Base-Sugar
52. The difference between thymine and uracil is: ___One Methyl Group On The Pyrimidine Ring,
53. In a double-stranded nucleic acid, cytosine typically base-pairs with: ____ Guanine.
54. Disruption of DNA can occur in the laboratory with alteration in ___ All Of The Above
55. Any regular. stable structure taken up by some or all of the nucleotides in a nucleic acid can be referred to as ___________ Secondary Structure
56. Nucleic acids are a polymer of nucleotide monomeric units. Each nucleotide consists of ___________

Base~ Sugar -~Phosphate

57. The DNA wrapped around the nucleosome core is continuous and joins one nucleosome core to the next -the linker DNA. This 50 bp DNA is complexed with the fifth type of histone, ---_____H1
58. The phosphodiester bonds that link adjacent nucleotides in both RNA and DNA: _____ Form Between The Planar Rings Of Adjacent Bases.
59. DNA that is not copied during the synthesis of mRNA is also called as _ Non-Template
60. Certain anticancer drugs. exert their cytotoxic effect by intercalating into the ------- groove of the DNA double helix, thus interfering with RNA and DNA synthesis ___ Narrow
61. The pI of glutamate is ___ 3.22
62. Which of the following amino acid is negatively charged at physiological pH? ___Aspartate
63. Which of the following refers to particularly stable arrangements of amino acid residues giving rise to recurring structural patterns? _____Secondary Structure
64. Keratin is present in ___. All Of These
65. Which of the following amino acid is involved in the hydrophobic interactions in the tertiary structure of protein? ___ Phenylalanine
66. The free energy of a protein molecule is influenced by ___ All of These
67. Which of the following diseases is caused by protein misfolding? ___All Of These
68. Iron is a _______. Transition Metal
69. Myoglobin can bind ____ molecules of oxygen. ____One
70. The partial pressure of oxygen (pO2) in lungs is about ____. 30 mmHg
71. In sickle cell anaemia, Glutamate is replaced with ____. Valine
72. Oxy hemoglobin dissociation curve describes the relationship of --------- Available Oxygen
73. Which one of the following is made up of two molecules of glucose? ___ Maltose
74. Which bond exists between the carbonyl group and oxygen of a hydroxyl group in ring structure of glucose? ___Covalent
75. In Benedict test, the formation of cuprous oxide is indicated by the formation of ____. Red ppt
76. Glucose 6 Phosphate is formed by the addition of phosphate group to C6 of glucose by _ linkage. Ester
77. E. coli convert lactose of milk to lactic acid by action of ____. Beta Galactosidase
78. Proteins are denatured by __. Temperature, pH, Organic Solvents
79. About ____ of amino acid residues in the myoglobin are found in alpha helices. ___78%
80. Haemoglobin is found exclusively in ___. Red Blood Cells
81. The partial pressure of oxygen (pO2) in lungs is about ____. 30 mmHg
82. In sickle cell anaemia, Glutamate is replaced with ____. Alanine

SUBJECTIVEs

1. Chargaff’s Rules.  Due to specific base pairing of DNA i.e A toT and G to C  In any sample of double-stranded DNA the amount of adenine equals the amount of thymine.  The amount of guanine equals the amount of cytosine  The total amount of purines equals the total amount of pyrimidines ;  i.e. A + G = T+ C.  The base pairs are held together by hydrogen bonds  Two between A and T  Three between G and C  These hydrogen bonds, plus the van der Waals and hydrophobic interactions between the adjacent stacked bases, stabilize the structure of the double helix. The base composition of DNA varies from one Spring 2023