The tobacco plant has been made resistant to the tobacco mosaic virus by:
1. introducing T -DNA of Agrobacterium
2. introducing a gene for vims coat protein
3. introducing meristematic activity in somatic cells
4. applying newer generation pesticides to the crops
At the trophic level of consumers, the rate at which food energy is assimilated, is called:
1. Secondary productivity
2. Gross primary productivity
3. Net primary productivity
4. None of these
The most important cause of loss of biodiversity today is:
1. habitat loss and fragmentation
2. over-exploitation
3. alien species invasions
4. co-extinctions
Photochemical smog does not contain :
(1) Ozone
(2) NOx
(3) PAN
(4) Carbon monoxide
Identify the incorrectly matched pair with respect to contamination of water
1. Minamata disease: Mercury
2. Blue baby syndrome: excessive nitrates
3. Black foot disease: excessive arsenic
4. Dental caries: excessive fluoride
Consider the following characters:
I. Air bladder
II. Operculum
III. Viviparity
The characters present in bony fishes include:
1. | I, II and III | 2. | I and III only |
3. | I and II only | 4. | II and III only |
A 0.1097 gm sample of As2O3 require 26.10 ml of KMnO4 solution for its titration. The molarity of KMnO4 solution is
1. 0.02
2. 0.04
3. 0.018
4. 0.3
The decomposition of H2O2 may be checked by adding a small quantity of phosphoric acid. This is an example of:
(1) neutralization
(2) negative catalysis
(3) positive catalysis
(4) catalytic poisoning
A mixture of benzaldehyde and formaldehyde on heating with aqueous (conc.)NaOH solution gives
1. benzyl alcohol and sodium formate
2. sodium benzoate and methyl alcohol
3. sodium benzoate and sodium formate
4. none of these
The correct order of the dipole moment of the following molecules is :
1. | I > II > III | 2. | I = II = III |
3. | III > II > I | 4. | I > III > II |
The product (s) obtained via oxymercuration-dermercuration of butyne would be
1. 2.
3. + 4.+ HCOOH
A concave lens of focal length 25 cm produces image the size of the object. The distance of the object from the lens is
(1) 225 cm
(2) 250 cm
(3) 150 cm
(4) 175 cm
A hollow conducting sphere is placed in an electric field produced by a point charge placed at \(P\) as shown in the figure. Let\(V_A ~,V_B~,V_C\) be the potentials at points \(A\), \(B\) and \(C\) respectively. Then:
1. \(V_A<V_B<V_C\)
2. \(V_A>V_B>V_C\)
3. \(V_C>V_B=V_A\)
4. \(V_A=V_B=V_C\)
The maximum kinetic energy of photoelectron emitted from the surface of work function f due to incidence of light of frequency n is E. If the frequency of incident light is doubled, then maximum kinetic of emitted photon will be
1. 2E
2. 2E - f
3. 2E + f
4. 2E + 2f
The following configuration of the logic gate is equivalent to
1. NAND gate
2. XOR gate
3. OR gate
4. NOR gate