Questions

Random fluctuations in the gene frequencies within a population Eliminate is the one which best describes genetic drift.

Damini-i-Koh was the land allocated to the Santhals. The Santhals could live on the land and practise plough agriculture, thus helping them to carry out settled agriculture.

Urea is a by product of amino acid catabolism, Which occurs in the liver. The nitrogen in the  amino acid becomes converted to ammonia and this is further converted by the liver into urea

One who believes in fate or luck is caled as Fatalist or determinist.

The photon is a type of elementary particle, the quantum of the electromagnetic field including electromagnetic radiation such as light, and the force carrier for the electromagnetic force. The photon has zero rest mass and always moves at the speed of light within a vacuum.

Ozone layer depletion is one of the most serious problems faced by our planet earth. Substances that Deplete the Ozone Layer (ODS) emission are responsible for ultraviolet radiations from the sun break them to release chlorine (from CFCs) and bromine (from methyl bromide and halons).