Expand ‘ELISA’. Why is this method preferred over conventional methods of diagnosis of diseases,?

Conventional sources of energy : Coal, petroleum, natural gas, fissionable materials like uranium.  Non-conventional sources of energy : Wind, Hydro Power, the Sun, Ocean Tidals Energy, Interior of the Earth, Biogas, Plants, Vegetable...

Preventive measures and biological control methods should be preferred for protecting crops because excessive use of chemicals leads to environmental problems. These chemicals are also poisonous for plants and animals....

Many bacteria are not culturable under normal conditions in the laboratory. This becomes a problem in studying their morphological, biochemical and other characterisations which are useful for their assessment.

Yes. One can use antibody against the enzyme (that is, responsible for the metabolism of phenylalanine) to develop ELISA based diagnostic technique. The patient where the enzyme protein is absent...

[Hint : They work well even with hard water and not form any scum.]

Conventional energy sources have been in common use since a long time, while non-conventional energy sources have recently come into use.

The population of London multiplied fourfold in the 70 years between 1810 and 1880 increasing from 1 million to 4 million. (i) London was a powerful magnet for migrant population, even...

a) Carbon cannot expand its octet but silicon can expand

Fe3+ is a better coagulating ion due to greater positive charge on it-