Why do you think the amount of DDT is maximum in birds?

Why do you think the zygote is dormant for sometime in a fertilized ovule?

Where do you find otolith?

What do you mean by antibiotic ?

It is said that the one cycle of cell division in human cells (eukaryotic cells) takes 24 hours. Which phase of the cycle, do you think occupies the maximum part of cell cycle?

Questions based on paragraph : One way of classifying stars is on the basis of their temperature . In the order of decreasing temperature , stars are divided into seven main types viz , O ,B,A,F,G,K and M . : What do you think will be a likely unit of average luminosity ? why ? :

Give an account of Hershey and Chase experiment. What did it conclusively prove? If both DNA and proteins contained phosphorusand sulphur do you think the result would have been the same?

Why do insects need moulting?

Why do the veins have valves?