2736: Consider the following techniques/phenomena:
1. Budding and grafting in fruit plants
2. Cytoplasmic male sterility
3. Gene silencing
Which of the above is/are used to create transgenic crops?
(a) 1 only
(b) 2 and 3
(c) 1 and 3
(d) None
2737: Which one of the following sets of elements was primarily responsible for the origin of life on the Earth?
(a) Hydrogen, Oxygen, Sodium
(b) Carbon, Hydrogen, Nitrogen
(c) Oxygen, Calcium, Phosphorus
(d) Carbon, Hydrogen, Potassium
2738: When the bark of a tree is removed in a circular fashion all around near its base, it gradually dries up and dies because
(a) Water from soil cannot rise to aerial parts
(b) Roots are starved of energy
(c) Tree is infected by soil microbes
(d) Roots do not receive oxygen for respiration
2739: In India people migrate from the countryside to the towns while in the U.S.A. it is just the other way. What is the reason for this?
(a) In U.S.A. people like the countryside more than the cities
(b) Use of urban land for purposes other than that of residence
(c) Lack of security of life and property in cities
(d) Lack of employment opportunities in cities
2740: Which one of the following is an element?
(a) Ruby
(b) Sapphire
(c) Emerald
(d) Diamond