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Artificial selection to obtain cows yielding higher milk output represents:

Option: 1

Stabilizing selection as it stabilizes this character in the population.


Option: 2

Directional as it pushes the mean of the character in one direction.


Option: 3

Disruptive as it splits the population into two, one yielding higher output and the other lower output.


Option: 4

Stabilizing followed by disruptive as it stabilizes the population to produce higher yielding cows.


Pollination in water hyacinth and water lily is brought about by the agency of

Option: 1

water


Option: 2

insects or wind


Option: 3

birds


Option: 4

bats


Which of the following regents would distinguish cis-cyclopenta-1, 2-diol from the trans-isomer?

Option: 1

Acetone


Option: 2

Ozone


Option: 3

MnO2


Option: 4

Aluminium isopropoxide


The orbital angular momentum of a p - electron is given as:

Option: 1

\sqrt 3 \frac{h}{{2\pi}}


Option: 2

\sqrt{\frac{3}{2}}\frac{h}{\pi}


Option: 3

\sqrt 6\frac{h}{{2\pi}}


Option: 4

\frac{h}{{\sqrt 2\pi}}


The correct order of decreasing acid strength of trichloroacetic acid (A), trifluoroacetic acid (B), acetic acid (C) and formic acid (D) is :

Option: 1

B > A > D > C


Option: 2

B > D > C > A


Option: 3

A > B > C > D


Option: 4

A > C > B > D


Two identical thin plano-convex glass lenses (refractive index 1.5) each having radius of curvature of 20 cm are placed with their convex surfaces in contact at the centre. The intervening space is filled with oil of refractive index 1.7. The focal length of the combination is:

Option: 1

-50 cm


Option: 2

50 cm


Option: 3

-20 cm


Option: 4

-25 cm


A mass m moves in a circle on a smooth horizontal plane with velocity v0 at a radius R0. The mass is attached to a string which passes through a smooth hole in the plane as shown.

The tension in the string is increased gradually and finally m moves in a circle of radius \frac{R_0}{2}. The final value of the kinetic energy is:

Option: 1

mv_0^{2}


Option: 2

\frac{1}{4}mv_0^{2}


Option: 3

2mv_0^{2}


Option: 4

\frac{1}{2}mv_0^{2}


Rachel Carson's famous book "Silent Spring" is related to:

Option: 1

Population explosion


Option: 2

Ecosystem management


Option: 3

Pesticide pollution


Option: 4

Noise pollution


Plasmodesmata are :

Option: 1

Locomotary structures


Option: 2

Membranes connecting the nucleus with plasmalemma


Option: 3

Connections between adjacent cells


Option: 4

Lignified cemented layers between cells


Which of the following is a pair of viral diseases ?

Option: 1

Common Cold, AIDS


Option: 2

Dysentery, Common Cold


Option: 3

Typhoid, Tuberculosis


Option: 4

Ringworm, AIDS


Consider the following reactions:

(i) H^{+}_{(aq)}+OH^{-}_{(aq)}= H_2O_{(l)},

\Delta H=-X_1\, \, \, kJmol^{-1}

 

(ii) H_2_(g_) +\frac{1}{2}O_2_(g_)= H_2O_(l_)

\Delta H= -X_2\, \, kJmol^{-1}

 

(iii) CO_2_(g_) +H_2_(g_)= CO_(g_) +H_2O,

\Delta H=-X_3\: \: kJmol^{-1}

 

(iv) C_2H_2_(g_) +\frac{5}{2}O_2_(g_)= 2CO_2_(g_)+ H_2O_(l_)

\Delta H= +X_4\: \: kJmol^{-1}

 

Enthalpy of formation of H_2O_(l_) is

 

Option: 1

+X_3\: \: kJmol^{-1}


Option: 2

-X_4\: \: kJmol^{-1}


Option: 3

+X_1\: \: kJmol^{-1}


Option: 4

-X_2\: \: kJmol^{-1}


A condenser of capacity C is charged to a potential difference of V1. The plates of the condenser are then connected to an ideal inductor of inductance L. The current through the inductor when the potential difference across the condenser reduces to V2 is

Option: 1

\left ( \frac{\text{C}\left ( \text{V}_{1}-\text{V}_{2} \right )^{2}}{\text{L}} \right )^{\frac{1}{2}}


Option: 2

\frac{\text{C}\left ( \text{V}_{1}^{2}-\text{V}_{2}^{2} \right )}{\text{L}}


Option: 3

\frac{\text{C}\left ( \text{V}_{1}^{2}-\text{V}_{2}^{2} \right )}{\text{L}}


Option: 4

\left ( \frac{\text{C}\left ( \text{V}_{1}^{2}-\text{V}_{2}^{2} \right )}{\text{L}} \right )^{\frac{1}{2}}


The reaction,

2A(g) + B(g) \rightarrow 3C(g) + D(g)

is begun with the concentrations of A and B both at an initial value of 1.00 M. When equilibrium is reached, the concentration of D is measured and found to be 0.25 M. The value for the equilibrium constant for this reaction is given by the expression:

Option: 1

\frac{(0.75)^30.25}{(1.00)^21.00}


Option: 2

\frac{(0.75)^30.25}{(0.50)^2(0.75)}


Option: 3

\frac{(0.75)^30.25}{(0.50)^2(0.25)}


Option: 4

\frac{(0.75)^30.25}{(0.75)^2(0.25)}


A source S1 is producing 1015 photons per second of wavelength 5000 \text{\AA}. Another source S2 is producing 1.02 x 1015 photons per second of wavelength 5100 \text{\AA}. Then (power of S2)/(power of S1) is equal to

Option: 1

0.98


Option: 2

1.00


Option: 3

1.02


Option: 4

1.04


Which one of the following does not exhibit the phenomenon of mutarotation?

Option: 1

(-) Fructose


Option: 2

(+) Sucrose


Option: 3

(+) Lactose


Option: 4

(+) Maltose


In unilocular ovary with a single ovule the placentation is

Option: 1

Axile


Option: 2

Marginal


Option: 3

Basal


Option: 4

Free Central


One of the free-living anaerobic nitrogen-fixer is

Option: 1

Azotobacter


Option: 2

Beijernickia


Option: 3

Rhodospirillum


Option: 4

Rhizobium


Heartwood differs from sapwood in:

Option: 1

presence of rays and fibres


Option: 2

absence of vessels and parenchyma


Option: 3

having dead and non-conducting elements


Option: 4

being susceptible to pests and pathogens


Guttation is the result of

Option: 1

Osmosis


Option: 2

Root pressure


Option: 3

Diffusion


Option: 4

Transpiration


Bulk of carbon dioxide (CO2) released from body tissues into the blood is present as

Option: 1

70% carbamino-haemoglobin and 30% as bicarbonate


Option: 2

Carbamino-haemoglobin in RBCs


Option: 3

Bicarbonate in blood plasma and RBCs


Option: 4

Free CO2 in blood plasma


Frogs differ from humans in possessing

Option: 1

Nucleated red blood cells


Option: 2

Thyroid as well as parathyroid


Option: 3

Paired cerebral hemispheres


Option: 4

Hepatic portal system


Test cross in plants or in Drosophila involves crossing

Option: 1

The F1 hybrid with a double recessive genotype


Option: 2

Between two genotypes with dominant trait


Option: 3

Between two genotypes with recessive trait


Option: 4

Between two F1 hybrids


Which one of the following is not an essential mineral element for plants while the remaining three are?

Option: 1

Cadmium


Option: 2

Phosphorus


Option: 3

Iron


Option: 4

Manganese


Two radioactive nuclei P and Q in a given sample decay into a stable nucleus R. At time t = 0, number of P species are 4N0 and that of Q are N0. Half-life of P (for conversion to R) is 1 minute whereas that of Q is 2 minutes. Initially there are no nuclei of R present in the sample. When number of nuclei of P and Q are equal the number of nuclei of R present in the sample would be:

Option: 1

\frac{5\text{N}_{0}}{2}


Option: 2

2N0


Option: 3

3N0


Option: 4

\frac{9\text{N}_{0}}{2}


Mole fraction of the solute in a 1.00 molal aqueous solution is :

Option: 1

1.7700


Option: 2

0.1770


Option: 3

0.0177


Option: 4

0.0344


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