Which one of the following organisms can serve as a biofertilizer for rice crop ?

At which stage in its life cycle does the silk worm yield the fibre of commerce ?

Match List-I (Diseases ) with List-II (Types of disease ) and select the correct answer using the codes given below the lists:
   List-I                     List-II
A. Haemophilia     1. Deficiency disease 
B. Diabetes          2. Genetic disease
C. Rickets            3. Hormonal disorder 
D. Ringworm        4. Fungal infection  

Soft drinks such as colas contain significant quantities of 

Some species are important in determing the ablity of a large number of other species to persist in the community. Such species belong to which biological communities?

The 'Stones' formed in human kidney consist mostly of 

"It begins as a single cell and grows into a merciless disease that claims millions of lives year after year. But scientists are steadily unlocking its mysteries,and the fight against it may now have reached a dramatic turning point. New discoveries promise better therapies and hope in the war against".... The disease referred to in the above quotation is 

Which one of the following is a useful functional association between fungi and the roots of higher plants ?

When some ants bite,they inject 

The sensation of fatigue in the muscles after prolonged strenuous physical work is caused by