• Biology - Section 1
71. 

Oxyreductases, transferases, hydrolases, lyases, isomerases and ligases are all classes of

A. hormones
B. enzymes
C. proteins
D. vitamins

72. 

Mutation is

A. a factor responsible for plant growth
B. a change which affects the offspring of F2 generation only
C. a change that is inherited
D. a change which affects the parents

73. 

Pollination by wind is called

A. anemophily
B. hydrophily
C. zoophily
D. entomophily

74. 

Pollen grains in plants are produced in

A. roots
B. leaves
C. flower
D. stem

75. 

Nitrogen is fixed in ecosystems in ways stated below. Which one of the statements below is false?

A. By cyanobacteria
B. By electrical discharges in the atmosphere
C. By industrially synthesised fertilizer
D. By denitrification