Prelims

Assertion (A) : Insect resistant transgenic cotton has been produced by inserting Bt gene. Reason (R) : The Bt gene is derived from a bacterium.

Consider the following statements : Glass can be etched or scratched by I. diamond. II. hydrofluoric acid. III. aquaregia. IV. cone, sulphuric acid. Which of these statements are correct ?

Assertion (A) : To dilute sulphuric acid, acid is added to water and not water to acid. Reason (R) : Specific heat of water is quite large.

Low temperatures (Cryogenics) find application in

Cobalt-60 is commonly used in radiation therapy because it emits

Which one of the following types of coal contains a higher percentage of carbon than the rest ?

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

When ants bite, they inject

Which one of the following agricultural practices is eco-friendly ?

Strips of two metals A and B are firmly joined together as shown in the figure(Before Heating) On heating, A expands more than B does. If this joined strip is heated, then it will appear as