81. Which of the following statements about Klenow fragment is false?
(A) Klenow fragment is derived from E. coli DNA polymerase I.
(B) It contains DNA polymerase activity.
(C) It contains 3’→5’ exonuclease activity.
(D) Klenow fragment is derived from large fragment of E. coli RNA polymerase I.
(E) It is lack of 5’→3’ exonuclease activity.

77. Insulin exerts its action through plasma membrane receptors to regulate the level of blood glucose. An elevated insulin level in the blood _______. (A) results from a below-normal blood glucose level (B) inhibits glycogen synthesis in liver and muscle (C) stimulates synthesis of fatty acids in liver and triacylglycerols in adipose tissue (D) inhibits glucose uptake by liver (E) stimulates glycogen breakdown in liver

78. Which of the following statements regarding polysaccharide is correct? (A) The glucose residues are linked by (β1→4) glycosidic bonds in cellulose. (B) In bacteria, dextrans are made up of (α1→4)-linked poly-D-glucose. (C) Chitin is a linear heteropolysaccharide composed of N-acetylglucosamine. (D) Glycogen is a polymer of glucoses with (α1→4)-linked branches. (E) Amylose is a branched glucose polymer.

79. Which of the following amino acids belong to ketogenic and glucogenic? (a) Trp (b) Phe (c) Tyr (d) Arg (e) Met (A) (a) (c) (e) (B) (a) (b) (c) (C) (b) (c) (e) (D) (b) (d) (e) (E) (a) (d) (e)

80. Which of the following statements regarding biosynthesis of fatty acids is correct? (A) NADH is required in the biosynthesis of fatty acids. (B) Fatty acids synthase I in vertebrates consists of 4 polypeptide chains. (C) Fatty acids synthase I is not a homodimer molecule. (D) HCO3 - is involved in biosynthesis of fatty acids. (E) There are 8 active sites in fatty acids synthase I.

82. Which of the following statements regarding β-oxidation of fatty acids is correct? (A) 16 acetyl-CoA molecules are produced by β-oxidation of palmitate. (B) One acetyl group is removed in one turn of β-oxidation. (C) In β-oxidation, ATP can be produced. (D) CO2 is generated by β-oxidation of palmitate. (E) The β-oxidation of unsaturated fatty acids has 4 basic steps.

83. Chartgraff's rules for DNA state that: (A) G+C = 39-46% in mammals (B) A=T and G=C (C) the sense strand is a right-handed helix (D) A=U and G=C (E) the minor groove is shallower than the major groove

84. Which of the following is a ribonucleoprotein required for the delivery of membrane and secretory proteins to the endoplasmic reticulum? (A) small ubiquitin-related modifier (SUMO) (B) signal recognition particles (SRP) (C) trigger factor (D) protein-conducting channel (PCC) (E) calnexin

85. Transcriptional activators that have variable positions and orientations are called _______. (A) enhancers (B) operators (C) introns (D) polycistrons (E) promoters

86. The peptide QYDG has a N-terminal _______ residue. (A) glutamic acid (B) glycine (C) glutamine (D) aspartic acid (E) alanine 

87. The reaction below is catalyzed by yeast alcohol dehydrogenase. Which of the following corresponds to X and Y? (A) X = NAD + H+ Y = NADH+ (B) X = NADH + H+ Y = NAD+ (C) X = NADPH + H+ Y = NADP+ (D) X = NAD+ Y = NADH + H+ (E) X = NADH+ Y =NAD + H+