Biological Molecules

1. In double helix of DNA, the two strands area) coiled around a common axisb) coiled differentlyc) coiled over protein sheathd) coiled around each other

2.Living cell contains 60-95% water. Water present in human body isa) 60-65%b) 70-75%c) 65-70%d) 75-80%

3. Nucleotides are building blocks of nucleic acids. Each nucleotide is a composite molecule formed bya) base- sugar- phosphateb) base- sugar- OHc) sugar-phosphated) (base sugar phosphate)n

4. The major role of minor elements inside living organisms is to act asa) Co factors of enzymesb) Binder of cell structurec) Constituent of hormonesd) Building blocks of important amino acids

5.Lipidsare insoluble in water because lipid molecules area) Hydrophilicb) Neutralc) Zwitter ionsd) Hydrophobic

6. ATP isa) vitaminb) Enzymec) Nucleic acidd) Nucleotide

7. Which of the following havecarbohydrateas prosthetic groupa) Glycoproteinb) Lipoproteinc) Nucleoproteind) Chromoprotein

8. Lactose is composed of

a) glucose + galactoseb) fructose+ galactosec) glucose + fructosed) glucose + glucose

9. In which of the following groups are all polysaccharides?a) Sucrose, glucose and fructoseb) Maltose, lactose and fructosec) glycogen, sucrose and maltosed) Glycogen, cellulose and starch

10.Amino acidsare produced froma) Proteinsb) Fatty acidsc) Essential oilsd) -keto acids

11.In RNA, thymine is replaced bya) adenineb) guaninec) cytosined) uracil

12. Which purine base is found in RNA?a) Thymineb) Uracilc) Cytosined) Guanine

13. Which of the following nucleotide sequences contains four pyrimidine bases?a) GATCAATGCb)UAGCGGUAAc) GCUAGACAAd) both b and c

14.Cellulose, the most important constituent of plant cell wall is made up of

a) Branched of glucose molecules linked by -1, 4 glycosidic bond in straight chain and -1,6 glycosidic bond at the site of branchingb) Unbrached chain of glucose molecules linked by --1,4 glycosidic bondc) Branched chain of glucose molecules linked by -1, 4 glycosidic bondd) Branched chain of glucose molecules linked by -1, 4 glycosidic bond in straight chain and -1,6 glycosidic bond at the site of branching

15.Enzymes, vitamins and hormones can be classified into a single category of biological chemicals, because all of thesea) Enhance oxidative metabolismb) Help in regulating metabolismc) are conjugated proteinsd) are exclusively synthesised in the body of a living organism as at present

1. a) coiled around a common axis2. c) 65-70%3. a) base- sugar- phosphate4. a) Co factors of enzymes5. d) Hydrophobic6. d) Nucleotide7. a) Glycoprotein8. a) glucose + galactose9. d) Glycogen, cellulose and starch10. a) Proteins11. d) uracil12. d) Guanine13. a) GATCAATGC14. b) Unbrached chain of glucose molecules linked by --1,4 glycosidic bond15. b) Help in regulating metabolism