71.

Oxyreductases, transferases, hydrolases, lyases, isomerases and ligases are all classes of
A. hormones B. enzymes
C. proteins D. vitamins
Answer and Explanation
Answer:B
Explanation: No answer description available for this question.
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
Answer and Explanation
Answer:C
Explanation: No answer description available for this question.
73.

Pollination by wind is called
A. anemophily B. hydrophily
C. zoophily D. entomophily
Answer and Explanation
Answer:A
Explanation: No answer description available for this question.
74.

Pollen grains in plants are produced in
A. roots B. leaves
C. flower D. stem
Answer and Explanation
Answer:C
Explanation: No answer description available for this question.
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
Answer and Explanation
Answer:D
Explanation: No answer description available for this question.