(c) G          8        VI       vii
     (d) H          1        II       vii
Ans: (a)
422. Which one among the following vitamins is necessary for blood clotting? [CDS 2012]
     (a) Vitamin A
     (b) Vitamin D
     (c) Vitamin K
     (d) Vitamin C
Ans: (c)
423. The fossil of Archaeopteryx represents the evidence of origin of [CDS 2012]
     (a) birds from reptiles
     (b) mammals from reptiles
     (c) reptiles from amphibians
     (d) mammals from birds
Ans: (a)
424. Which one among the following statements is correct? [CDS 2012]
     (a) All proteins are enzymes
     (b) All enzymes are proteins
     (c) None of the enzymes is protein
     (d) None of the proteins is enzyme
Ans: (b)
425. AIDS is caused by Human Immunodeficiency Virus (HIV), which is [NDA 2011]
     (a) Retro virus
     (b) Lente virus
     (c) Arbo virus
     (d) Immune virus
Ans: (a)
426. Which one among the following statements regarding heart sound is correct? [NDA 2011]
     (a) Heart sounds are caused by the internal blood flow inside the heart
     (b) Heart sounds are caused by the external blood flow outside the heart
     (c) Heart sounds are caused by opening and closing of heart valves
     (d) Normal sounds are called "murmurs"
Ans: (c)
427. Which one among the following cell organelles is semi-permeable? [NDA 2011]
     (a) Cell membrane
     (b) Plasma membrane
     (c) Cell wall
     (d) Nucleus
Ans: (b)
428. Which one of the following gases is essential for photosynthesis process? [UP PCS 2011]
     (a) CO
     (b) CO2
     (c) N2
     (d) O2
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