61.

Mumps is a disease caused by
A. fungus B. bacterium
C. virus D. None of these
Answer and Explanation
Answer:C
Explanation: No answer description available for this question.
62.

Rain water helps to increase the ____ to some extent.
A. phosphorous contents B. nitrogen contents
C. calcium contents D. potash contents
Answer and Explanation
Answer:C
Explanation: No answer description available for this question.
63.

Number of chromosomes in Down's syndrome is
A. 46 B. 47
C. 48 D. 49
Answer and Explanation
Answer:B
Explanation: No answer description available for this question.
64.

Plants are killed in winter by frost
A. because of desiccation and mechanical damage to the tissues B. because no photosynthesis takes place at such low temperature
C. because respiration ceases at such low temperature D. because there is no transpiration
Answer and Explanation
Answer:A
Explanation: No answer description available for this question.
65.

One of the following is most suitable for study of mutations
A. Haploids B. Diploids
C. Tetraploids D. Polyploid
Answer and Explanation
Answer:A
Explanation: No answer description available for this question.