150. Which of the following are involved in the making up of a DNA nucleotide? [Railways 1994]
     1) Phosphoric acid
     2) Deoxyribose sugar
     3) Nitrogenous base
     (a) 1 and 2
     (b) 2 and 3
     (c) 1 and 3
     (d) 1, 2 and 3
Ans: (d)
151. Which of the following organelles is present in bacteria or prokaryotic cell? [IFS 1989]
     (a) Vacuoles
     (b) Mitochondria
     (c) Ribosomes
     (d) Golgi bodies
Ans: (c)
152. The unit structure of which gene is made up of is: [IFS 1989]
     (a) RNA
     (b) nucleotides
     (c) DNA
     (d) endoplasmic reticulum
Ans: (c)
153. A molecule of glucose on complete oxidation yields ATP molecules in case of aerobic respiration.
     (a) 36
     (b) 38
     (c) 40
     (d) 42
Ans: (a)
154. In anaerobic respiration, the net gain of ATP per glucose molecule oxidised is:
     (a) 2
     (b) 4
     (c) 6
     (d) 30
Ans: (a)
155. Which of the following is the correct sequence of the different phases of mitotic division?
          1) Metaphase
          2) Anaphase
          3) Prophase
          4) Telophase
     (a) 1,2,3,4
     (b) 1,3,2,4
     (c) 3,2,1,4
     (d) 3,1,2,4
Ans: (d)
156. In which one of the following types of cell divisions does crossing over of chromosomes takes place? [CDS 1991]
     (a) Mitosis
     (b) Meiosis