336: Assertion (A):
Scientists can cut apart and paste together DNA molecules at will, regardless of the source of the molecules.
Reason (R):
DNA fragments can be manipulated using restriction endonucleases and DNA ligases.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is NOT a correct explanation of A
(c) A is true but R is false
(d) A is fasle but R is true
337: Isotopes of the same element differ in the number of:
(a) Protons
(b) Neutrons
(c) Electrons
(d) Positrons
338: Why DDT is banned in western countries?
(a) It remains in environment for a long time
(b) The insects are immunised
(c) It is a highly poisonous insecticide
(d) None of the above
339: Who among the following was a prominent leader of the Congress Socialist Party ?
(a) M. N. Roy
(b) Ganesh Shankar Vidyarthi
(c) Pattam Thanu Pillai
(d) Acharya Narendra Dev
340: Which one among the following covers the highest percentage of forest area in the world?
(a) Temperate Coniferous forests
(b) Temperate Deciduous forests
(c) Tropical Monsoon forests
(d) Tropical Rain forests