Young's modulus of the material of a wire is 18 x 1011 dyne cm-2. Its value in SI is
Unit of young's moduls Y in SI units is NM-2.
1 cm = 10-2M
Y = 18 x 1011 x
Y = 18 x 1011 x 10-1Nm-2
= 18 x 1010 Nm-2
Steam at 100°C is passed into 1.1 kg of water contained in a calorimeter of water equivalent 0.02 kg at 15°C till the temperature of the calorimeter and its contents rises to 80°C. The mass of the steam condensed in kg is
mL + m(100 - 80)
= 1.1 x 1 x (80-15) + 0.02 x (80-15)
m x 540 + 20m = 71.5 + 1.30
560m = 72.80
∴ m = 0.130
A and B are two vectors and θ is the angle between them, if |A x B| = √3 (A.B) , the value of θ is
Given, |A x B| = √3(A.B)
⇒ ABsin θ = √3AB cos θ
tan θ = √3
⇒ θ = 60°
Light enters at an angle of incidence in a transparent rod of refractive index n. For what value of the refractive index of the material of the rod the light once entered into it will not leave it through its lateral face whatsoever be the value of angle of incidence?
Let a ray of light enter at A and the refracted beam This is incident at an angle θ. For no refraction at the lateral face, θ > C or, sin θ > sin C
But θ + r = 90°
⇒ θ = (90° - r)
∴ sin (90° - r) > sin C
or cos r > sin C ...(1)
From Snell’s law, n = sini / sinr
⇒ sinr = sini /n
∴ equation (1) gives
Maximum value of sin i = 1
A car wheel is rotated to uniform angular acceleration about its axis. Initially its angular velocity is zero. It rotates through an angle θ1 in the first 2s, in the next 2s, it rotates through an additional angle θ2, the ratio of θ2/θ1 - is
a = θ/t2
The turn ratio in a step up transformer is 1:2. If a cell of 1.5 V is connected across the input, then the voltage across the output will be
A transformer cannot step up a d.c. input so output potential here will be zero. No potential will be induced in the secondary coil.
A high altitude, a body explodes at rest into two equal fragments with one fragment receiving horizontal velocity of 10 m/s. Time taken by the two radius vectors connecting point of explosion of fragments to make 90° is
As the body at rest explodes into two equal parts, they acquire equal velocities in opposite directions according to conservation of Momentum.
When the angle between the radius vetors connecting the point of explosion to the fragments is 90°, Each radius vector makes an angle 45° with the vertical. To satisfy this condition, the distance of free all AD should be equal to the horizontal range in same interval of time.
AD = 0 + 1/2 x 10t2 = 5t2
DB = ut + 10t
5t2 = 10t
⇒ t = 2s
Consider two thin identical conducting wires covered with very thin insulating material. One of the wires is bent into a loop and produces magnetic field B1, at its centre when a current I passes through it. The ratio B1 : B2 is:
where, a is the radius of loop.
Now, for coil B =
at the centre x = radius of loop
A thin circular ring of mass M and radius r is rotating about its axis with a constant angular velocity ω. Four objects each of mass m, are kept gently to the opposite ends of two perpendicular diameters of the ring. The angular velocity of the ring will be
Initial angular momentum of ring,
L = Mr2ω
Final angular momentum of ring and four particles system L = (Mr2 + 4mr2)ω
As there is no torque on the system, therefore angular momentum remains constant.
When light of wavelength 300 nm (nanometre) falls on a photoelectric emitter, photoelectrons are emitted. For another emitter, however, light of 600 nm wavelength is sufficient for creating photoemission. What is the ratio of the work functions of the two emitters?
The mean radius of the earth is R, its angular speed on its own axis is ω and the acceleration due to gravity at earth's surface is g. What will be the radius of the orbit of a geostationary satellite?
The linear velocity of a rotating body is given by If and , then the magnitude of is
Aerofoils are so designed that the speed of air
The aerofoils are so designed that,
So that the aerofoil get a lifting force in upward direction. According to Bernoulli's theorem, where the pressure, is large, the velocity will be minimum or vice-versa
What is the work done in blowing a soap bubble of radius 0.2 m? (The surface tension of soap solution is 0.06 N/m)
Work done = increase in surface area x surface tension
= 2 x 4π x (.2)2 x .06
= 8π x 4 x 10-2 x 6 x 10-2 J
= 192 π x 10-4 J
[Soap bubble has two- surfaces]
An AC source is connected with a resistance R and an uncharged capacitance C in series. The potential difference across the resistor is in phase with the initial potential difference across the capacitor for the first time at the instant (assume that, at t = 0, emf is zero)
V = V0 sinωt
Vr = V0 sinωt
Vc = V0sin(wt - π/2)
V & VR are in some phase, while Vc lays V (or UR) by 90°.
Now, VR is in some phase with intitial potential different accross the capicitor for the first time when
The molar specific heat at constant pressure of an ideal gas is (7/2) R. The ratio of specific heat at constant pressure to that at constant volume is
A small steell ball falls through a syrup at a constant speed of 1.0 m/s. If the steel ball is pulled upwards with a force equal to twice its effective weight, how fast will it move upward?
We = Effective weight
kv = We .............(i)
2We - We = kv'
or kv'= (2We - We) ............... (ii)
From eqs. (i) & (ii) we get.
V' = V =1.0 m/s
The correct statement of the law of equipartition of energy is
According to the law of equipartition of energy, the gas possesses equal energies in all the three direction x, y and z-axis.
The fundamental frequency of a closed pipe is 220 Hz. If 1/4 of the pipe is filled with water, the frequency of the 1st overtone of the pipe now is
Fundamental frequency of closed pipe
If 1/4 of the pipe is filled with water, then remaining length of fair column is
Now, fundamental frequency
First overtone = 3 x fundamental frequency.
An electric dipole placed in a non-uniform electric field experiences
An electric dipole placed in a non-uniform electric field experiences a torque and a net force. In a uniform field it experiences only torque.
What is the total electric flux leaving a spherical surface of radius 1 cm and surrounding at electric dipole?
From Gauss's theorem.
φ = Net charge enclosed by the surface/Eo
The net charge due to a dipole is zero, Hence φ = 0.
The transfer ratio β of a transistor is 50. The input resistance of the transistor when used in the common emitter configuration is 1 kΩ the peak value of the collector A.C. current for an A.C. input voltage of 0.01 V,is
A current of 1.5 A flows through a copper voltmeter. The thickness of copper deposited on the electrode surface of area 50 cm2 in 20 min will be (Density of copper = 9000 kgm-3 and ECE of copper = 0.00033 g C-1)
A body falls on the ground from a height of 10 m and rebounds to a height of 2.5 m. Then the ratio of velocities of the body just before and just after the collision will be
Let v1 and v2 be the velocities of the body just before the collision & and after the collision.
Two coils X and Y are placed in a circuit such that a current changes by 3 A in coil X and the magnetic flux changes of 1.2 Wb occurs in Y. The value of mutual inductance of the coils is
φ = Ml,
Hence, dφ = Mdl
Here dφ = 1.2 wb and dl = 3A
Hence,M = 0.4 H
A point particle is held on the axis of a ring of mass m and radius r at a distance r from its centre C. When released, it reaches C under the gravitational attraction of the ring. Its speed at C will be
Let 'M' be the mass of the particle
Now, Einitial = Efinal
An electromagnetic wave going through vacuum is described by E = E0sin(Kx - ωt).
Which of the following is independent of wavelength?
Here, kα = θo or k = θo/x and ωt = θo/t or w = θo /t
Where,v is the velocity of electromagnetic wave, which is independent of wavelength of wave.
A piece of copper and another of germanium are cooled from room temperature to 80° K. The resistance of
Copper is a metal whereas Germanium is Semi-conductor.
Resistance of metal decreases and semiconductor increases with decrease in temperature.
In young's experiment, two coherent sources are 0.90 mm apart and fringes are observed at a distance of 1 m, if 2nd dark fringe is at 1 mm distance from central fringe, then wavelength of the monochromatic light will be
d = 0.90 x 10-3 M, D = 1 m
λ = 6 x 10-5 cm
Current II in the following circuit is
Applying; 1st law of Kirchoff's,
I3 = I1 + I2
Applying 2nd law of Kirchhoff
in Mesh ABCFA
-30I1 + 40 - 40I3 = 0 ........ (i)
in Mesh FCDEF
40I3 - 40 - 80 + 40I2 = 0 ........ (ii)
putting I3 from (i) in (ii) and (iii) we get
-30I1 + 40 - 40I1 - 40I2 = 0
or, -70I1 - 40I2 = 40
or, 7I1, + 4I2 = 4 .................. (iv)
and 40I1 +40I2 - 40 - 80 + 40I2 = 0
or, 40I1 +80I2 =120
or, 4I1 +8I2 = 12
or, 2I1 + 4I2 = 6 ...... ........ (v)
gives 5I1 = -2
I1 = - 0.4 A
Monochromatic light of wavelength 3000 is incident on a surface area 4 cm2. If intensity of light is 150 mWm-2, then rate at which photons strike the target is
= 9 x 1013 s-1
A proton and an α - particle enter a uniform magnetic field perpendicularly with the same speed. If proton takes 25 μ second to make 5 revolutions, then the time period for the α - particle would be
Time taken by proton to make one revolution
= 25/5 = 5 μ sec
In an unbiased p-n junction, holes diffuse from the p-region to n-region because
In an unbiased p - n junction, the diffusion of charge carries across the junction takes place from heigher concentration to lowar concentration.
One of the lines in the emission spectrum of Li2+ has the same wavelength as that of the 2nd line of Balmer series in hydrogen spectrum. The electronic transition corresponding to this line is n= 12 → n = x. Find the value of x.
For 2nd line of Balmer series in hydrogen spectrum
which is satisfied by n = 12 → n = 6
The total energy of electron in the ground state of hydrogen atom is -13.6 eV. The kinetic energy of an electron in the first excited state is
The energy of hydrogen atom when the electron revolves in nth orbit, is
ε = -13.6 eV
in the ground state, n = 1
ε = -13.6/12 = -13.6 eV
for n = 2ε = = -3.4eV
So kinetic energy of electron in the first excited state (i.e for n =2), is
= - E = 3.4 eV
A student when discussing the properties of a medium (except vacuum) writes:
Velocity of light in vacuum = velocity of light in medium. This formula is
The formula can be written as
This formula is dimensionally correct as both the sides are dimensionless. Numerically, this ratio is equal to refractive index which is > 1. Hence, the equation is numerically incorrect.
The number of significant figures in 0.06900
In 0.06900, the number of significant figures is 4 Which includes 6.9 and last two zero.
In thermodynamic processes, which of the following statements is not true?
In an isochoric process volume remains constant whereas pressure remains constant in isobaric process.
In similar calorimeters, equal volumes of water anc alcohol when poured take 100 s and 74 S respectively to cool from 50°C to 40°C. If the thermal capacity of each calorimeter is numerically equal to volume of either liquid, then the specific heat capacity of alcohol is (Given, relative density of alcohol as 0.8 and specific heat capacity of water as 1 cal/g/°C)
Let, V be volume of either liquid, mass of water = u x 1 g
Mass of alcohol = V x 0.8 = 0.8ug
Rate of cooling of the water calorimeter
Rate of cooling of alcohol calorimeter
As rate of cooling of both is same
Equipotential surfaces associated with an electric field which is increasing in magnitude along the x-direction are
Equipotential surface is always perpendicular to the direction of electric field. As the field is along x-direction, equipotential surface must be parallel to yz-plane.
To produce an achromatic combination a convex lens of focal length 42 cm and dispersive power 0.14 is placed in contact with a concave lens of dispersive power 0.21. The focal length of the concave lens is
Focal length of concave lens = 63 cm.
A hemispherical glass body of radius 10 cm and refractive index 1.5 is silvered on its curved surface. A small air bubble is 6 cm below the flat surface inside it along the axis. The position of the image of the air bubble made by the mirror is seen :
Given, radius of hemispherical glass
∴ Focal length f = 10/2 = -5cm
u = (10-6) = -4 cm.
By using mirror formula,
v = 20 cm
below flat surface.
A body of mass 1 kg is fastened to one end of a steel wire of cross-sectional area 3 x 10-6m2 and is rotated in horizontal circle of radius 20 cm with constant speed 2 m/s. The elongation of the wire is (Y = 2 x 1011 N / m2)
Stress = T/A =
Given, l = 20 x 10-2M,
⇒ 67 x 10-5 M
Two bodies moving towards each other collide and move away in opposite direction. There is some rise in temperature of bodies because a part of the kinetic energy is converted into
There is rise in temperature so, mechanical energy is converted into heat energy.
In each of the following questions a statement of Assertion is given followed by a corresponding statement of Reason just below it Of the statements mark the correct answer as
(a) If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion
(b) If both Assertion and Reason are true but the Reason is not correct explanation of the Assertion
(c) If Assertion is true but Reason is false
(d) If both Assertion and Reason are false
Q. Assertion (A) Making or breaking of current in a coil produces no momentary current in the neighbouring coil of another circuit.
Reason (R) Momentary current in the neighbouring coil of another circuit is an eddy current.
Before making current in a coil, the current is zero and active before breaking the current is maximum, in other words, it is constant in both the cases, obviously on making changing or breaking the current in a ciruit, the current stants changing. The changing current produces changing magnetic bielo. which in turn produces induced current neighbouring coil of the circuit.
How many moles of lead (II) chloride w ill be formed from a reaction between 6.5 g PbO and 3.2 g HCl?
The reaction is:
PbO + 2HCl → PbCl2 + 2H2O
Case I: Let PbO is completely consumend:
∴ 1 mol PbO gives 1 mol PbCl2
∴ 0.029 mol PbO will give 0.029 mol PbCl2
Case II: Let HCL is completely consumed
∵ 2 mol Hcl gives 1 mol PbCl2 .
∴ 0.087 mol HCl will give mol pbcl2
When NaCl is flopped with 1.0 x 10-3 mole of SrCl2, the number of cation vacancy is
Two Na+ ions are replaced by one Sr2+ ion to maintain electrical neutrality.
Hence, number of vacancies
= Number of Sr2+ ions doped
= 1.0 x 10-3 x 6.02 x 1023
= 6.02x 1020
In an atom, an electron is moving with a speed of 600 m/sec with an accuracy of 0.005% . Certainty with which the position of the electron can be located, is (h = 6 .6 x 10-34 kg m2s-1, mass of electron me = 9.1 x 10-31 kg)
Uncertainity in velocity =
Uncertainty in position of electron, i.e., Δx may be calculated as,
Which of the following arrangements does not represent the correct order of the property stated against it ?
V = 3d34s2;
V2+ = 3d3 = 3 unpaired electrons
Cr = 3d54s1;
Cr2+ = 3d4 = 4 unpaired electrons
Mn = 3d54s2;
Mn2+ = 3d5 = 5 unpaired electrons
Fe = 3d64s2;
Fe2+ = 3d6 = 4 unpaired electrons Hence the correct order of paramagnetic behaviour
V2+ < Cr2+ = Fe2+ < Mn2+
In which of the following the central atom is sp3 hybridised?
Using formula H =
i e., sp2 hybrid
, i.e, sp3d2 hybrid
, i.e, sp3d hybrid
i.e, sp3d2 hybrid
Among the following the aromatic compound is
Only (a) obeys Huckel’s rule
For vaporization of water at 1 atmospheric pressure, the values of ΔH and ΔS are 40.63 KJ mol-1 and 108.8 JK-1mol-1 respectively. The temperature when Gibbs energy change (ΔG) for this transformation will be zero is
ΔG = ΔH - TΔS
Calculate the pH of a solution obtained by mixing 2 mL of HCl of pH = 2 and 3 mL of solution of KOH of pH = 12
[H+] in HCl solution (pH = 2) = 10-2M;
[OH-1] in KOH solution
(pOH= 14 -12 = 2) = 10-2 M
Excess m Mol of OH- in 5 mL mixture = 3 x 10-2 - 2 x 10-2 = 1.0 x 10-2;
[OH-] in mixture =
= 2 x 10 -3 M;
pOH = - log 2 x 10-3 = 3 - log 2;
pH = 14 - (3 - log 2) = 11.30
For a given exothermic reaction, kP and k'p are the equilibrium constants at temperature T1 and T2 respectively. Assuming that heat of reaction is constant in the temperature range between T1 and T2. It is readily observed that
The equilibrium constant at two different temperatures for a thermodynamic process is given by
Here K1 and K2 are replaced by KP and K’P Therefore
For exothermic reactions, T2 > T1 and ∆H = -ve
Kp > K’p
Paramagnetism of Cr(Z = 24), Mn2+(Z = 25) and Fe3+ (Z = 26) arex, y and z respectively. They are in the order
Number of unpaired electrons in Cr, Mn2+ and Fe3+ are 6, 5 and 5 respectively.
Number of moles of KMn0-4 required to oxidise one mole of ferrous oxalate completely in acidic medium will be
The reaction involved is
The correct IUPAC name of the compound
[ ∴ the order of preference of substituent groups is - CHO > - N02 > - OCH3]
Which one of the alkali metals forms only the normal oxide, M20 on heating in air?
4Li + O2 → 2Li20
Vapour pressure (in torr) of an ideal solution of two liquids A and B is given by: P = 52XA +114 where XA is the mole fraction of A in the mixture.The vapour pressure (in torr) of equimolar mixture of the two liquids will be:
or PºA = 166 torr
Which of the following compound is not a protonic acid?
B(OH)3 is not a protonic add. However, it reacts with water and receives OH- ions to complete its octet and releases H+ ions.
The incorrect statement among the following is:
The IUPAC name nomenclature of (CH3)3C - CH = C(CH3)2 is
(2,4,4- Trimethylpent -2- ene)
Which of the following compound is expected to be optically active?
An optically active compound contains a chiral carbon atom.
(contains chiral carbon atom)
The hydrocarbon which dees not decolourise alkaline KMnO4 solution and also does not give any precipitate with ammonical silver nitrate is
As benzene is resonance stabilized, so, it does not react with alk. KMn04. It has no acidic hydrogen atom, hence, it cannot react with ammoniacal AgNO3 solution.
Which of the following can be predicted from electronegativity values of elements ?
Greater the difference of electronegativities, more polar is the bond.
Photochemical smog is related to the pollution of
Photochemical smog occurs due to presence of oxides of nitrogen CO and hydrocoarbons in atmosphere.
The concentration of a reactant X decreases from 0.1 M to 0.005 M in 40 min. If the reaction follows first order kinetics, the rate of the reaction when the concentration of X is 0.01 M will be
For a first order reaction, we have
Now, rate = k x [reactant]
When [x] = 0.01 M
∴ rate =
= 7.5 x 10-4 M min-1
The mass of carbon Anode consumed (giving only carbon dioxide) in the production of 270 kg of aluminium metal from bauxite by hall process is
2Al203 + 3C → 4Al + 3C02
2mol 3mol 4mol
(2 x 102)g (3 x 12)g (4 x 27)g
∵ 108 kg Al is produced by 36 kg of carbon
∴ 270 kg Al is produced by 36/180 x 270 kg carbon
= 90 kg
Aniline, chloroform and alcoholic KOH react to produce a bad smelling substance which is
This is isocyanide test
In which of the following molecules/ions BF3, N02- , NH2- and H20, the central atom is sp2 - hybridized?
Vapour density of the equilibrium mixture of the reaction
S02Cl2(g)S02(g) + Cl2(g ) is 50.0.
Percent dissociation of S02Cl2 is:
A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is
For fcc lattice,
=0.3535 x 408 pm = 144 pm
Diameter = 2r = 288 pm.
The pair in which phosphorous atoms have a formal oxidation state of +3 is :
Phosphorous acid contain P in +3 oxidation state.
In the electrolysis of which solution, OH- ions are discharged in preference to Cl- ions?
In very dilute solution of NaCl, the following reactions take place on electrolysis
Anode : 20H- → H20 + 1/2O2 + 2e- Cathode : 2H+ + 2e- → H2
Mole fraction of methanol in its aqueous solution is 0.5. The concentration of solution in terms of percent by mass of methanol is
Mass of methanol in 1 mol solution
= 0.5 x 32= 16 g
Mass of water in solution = 0.5 x 18 = 9g
% by mass of methanol =
The dispersed phase and dispersion medium in soap lather are respectively
Soap lather is a dispersion of gas in liquid.
Electrolytic reduction of alumina to aluminium by Hall- Heroult process is carried out
Which one has the highest boiling point?
As the size of the element increases down the group from He to Xe, the magnitude of the vander walls forces of attraction also increase in the same way and hence the boiling points increases accordingly. Thus, Xe has the highest b.p.
The major product formed in the reaction is:
Hyperconjugation —> more α H, more reactive o,p site.
Cobalt (III) chloride forms several octahedral complexes with ammonia, which of the following will not give test for chloride ions with silver nitrate at 25°C?
As cobalt forms octahedral complexes for which coordination number = 6, the formulae of the give: complexes will be [Co(NH3)5Cl]Cl2[Co(NH3)6]Cl3 [Co(NH3)3Cl3] and [Co(NH3)4Cl2]Cl
Thus, only (c) does not have any ionizable chloride ion.
The hybridization of P in P03-4 is the same as of
Among the following sets of reactants which one produces anisole?
Which statement is not true regarding biodegrdable detergent?
For making distriction between 2 - pentanone and 3- pentanone, the reagent employed is
I2 / NaOH (iodoform test)
At 0° C and one atm pressure, a gas occupies 100 cc. If the pressure is increased to one and a halftime and temperature is increased by one third of absolute temperature, then final volume of the gas will be
V = 88.9 cc
The one letter code for the amino acid tryptophan is
One letter code for tryptophan is' W
The fatty acid which shows reducing property is
Formic acid has aldehydic grouping
Among cellulose, (poly (vinyl chloride), nylon and natural rubber, the polymer in which the intermolecular force of attraction is weakest is
Natural rubber has the weakest inter molecular forces of attraction.
The maximum prescribed concentration of copper in drinking water by ISI (Indian Standard Institution) is:
Maximum prescribed concentration of Gu in drinking water by ISI is 0.05 mg/L.
How many stereoisomers does this molecule have? CH3CH = CHCH2CHBrCH3
CH3CH = CHCH2CHBrCH3 is an alkene having different substituents at each carbon atom of the double bond. Therefore, it exists in two geometrical isomers, ie. C is and trans. Since the given compound also has a chiral centre, therefore, each geometrical isomer has a pair of enantiomers. Thus in all, there are 2 x 2 = 4 stereoisomer.
The correct surgical procedure as a contraception method is
Vasectomy is a surgical procedure for male sterilization or permanent contraception, a minor surgery to block sperm from reaching the semen.
Which one of the following is a living fossil?
Identify the correct statement among following regarding the growth in plants
Growth is indeterminate, they stop growing when fruits set on the terminal or top bud example of such plants are coconut trees, dates etc
Bryophytes resemble algae in which of the following aspects?
Debove's membrane is a layer of
Debove’s membrane is a layer of connective tissue cells between the epithelium and basement tissue of respiratory and intestinal epithelia.
When gynoecium is present in the top most position of thalamus, the flower is known as
Niche overlap indicates
Niche/ecological niche is a specific part of habitat occupied by individuals of a species which is circumscribed by its range of tolerance, range of movement, microclimate, type of food and its availability, shelter, type of predator and timing of activity. Habitat has several ecological niches and supports a number of species. An ecological niche is used by a single species. Two or more species cannot use the same niche despite having a mutualistic association. Organisms or populations in the competition have a niche overlap of a limited resource for which they compete. Both owl and cat feed on shrews and mice. They occupy the same niche because of being ecological equivalents though their habitats are different.
So, the correct answer is 'Sharing of one or more resources between the two specie
In land plants, the guard cells differ from other epidermal cells in having
Guard cells contains chloroplast, so they can manufacture food by photosynthesis. They are the only epidermal cells that can make sugar.
Connective tissue is
Connective tissues are mesodermal layers that originates with intercellular spaces of organs to provide support to the body.
In which of the following cell organelles would you expect to find the biochemical reactions that harness energy from the breakdown of sugar molecules to synthesize large amounts of ATP?
The mitochondrion is the powerhouse of the cell. Here the bulk of the reactions that manufacture ATP take place.
Photophosphorylation differs from oxidative phosphorylation in requiring input of energy in the form of
Oxidative phosphorylation requires NAD while photophosphorylation used energy by proton, electron that are present in light thus Inorganic phosphate (ip) in photosynthesis is called photophosphorylation.
The diagram below is a model demonstrating the mass flow hypothesis of translocation.
What are the structures represented by W, X, Y and Z and what is the direction of flow of solution along W?
Y represents the site of photosynthesis, where more glucose has been manufactured, whilst there is less glucose in the medium where the roots Z are placed in. W thus is the phloem where the photosynthates are transported from the leaves Y to the roots Z. X is the xylem which helps in the transportation of water from the roots Z to leaves Y.
In DNA model of Watson and Crick, the major grooves represent one of the following sites
DNA is a molecule that carries two grooves, the major is wide and the other, the minor groove is wide both are opposite to each other. Some acidic proteins bind at major groove sites and other to minor groove sites.
A plant cell placed in pure water will
Sickle-cell anaemia is example of
Sickle cell disease is an inherited blood disorder that affects the people it is an example of autosomal heritable disease.
In which stage of the cell cycle histone proteins synthesised in a eukaryotic cell?
During the S phase or synthetic phase of interphase, replication of DNA and synthesis of histone proteins occur. New histones are required in massive amounts immediately at the beginning of the S period of DNA synthesis to provide the new DNA with nucleosomes.
So, the correct option is 'During S-phase'.
Monoecious plant of Chara shows occurrence of
Chara is a genus of green algae. They are multicellular and superficially resemble land plants. They prefer less oxygenated and hard water. They are covered with calcium carbonate deposits and are commonly known as stoneworts.
Chara reproduces by both sexual and vegetative modes. Sexual reproduction of Chara is an advanced oogamous type. The sex organs are macroscopic and large. The male sex organ is yellow to red in colour, called globule. The female sex organ is more or less oval and green in colour and called nucule or oogonium. On maturity, globule develops into antheridia filaments made up of antheridium cells. Oogonium is always situated singly above the globule or antheridium.
Most of the species are homothallic or monoecious ( i.e. male and female sex organs develop on the same plant ) but some are heterothallic or dioecious ( i.e. male and female sex organs on different plants ).
Thus, the correct answer is option B.
Differentiation of shoot is controlled by
Differentiation of shoot is controlled by low auxin concentration. While in tissue culture auxin concentration is made high to promote rooting.
Two common characters found in centipede cockroach and crab are
Some arthropods like Crab and cockroach have hardened exoskeleton ie. Chitinous exoskeleton and jointed legs are two most common characters of centipede Cockroach and Crab
Nuclear DNA exists as a complex of proteins called ______ that condenses into _______ during cellular division.
The complex of proteins and DNA is called chromatin that form chromosomes within the nucleus of eukaryotic cells. Chromosomes are only present during cell reproduction.
Both, autogamy and geitonogamy are prevented in
Unisexual flowers or plants prevent both autogamy and geitonogamy e.g. papaya.
Which of the following pathways outlines the order of events during aerobic cellular respiration? first—>last
Glucose is converted to hexose phosphate, which is broken down to triose phosphate, which is subsequently converted to, pyruvate. Pyruvate enters the Krebs cycle, producing carbon dioxide, reduced NAD and ATP. Reduced NAD enters the electron transport chain, where oxygen is reduced to water and ATP is produced.
Heart to pump blood evolved for the first time in
Much like humans, annelids also have a closed circultatory system, which means the blood pumping from heart to organ.
In tissue culture, roots can be induced by
You are given a fairly old piece of dicot stem and a dicot root. Which of the following anatomical structures will you use to distinguish between the two?
The part of the primary xylem that develops first consisting of narrow, thin-walled cells called protoxylem that is an anatomical structure use tc distinguish old pieces of dicot stem and a dicot root.
Which one of the following is a natural growth inhibitor?
The causative agent of mad-cow disease is a
Mad Cow disease is a fatal neurodegenerative disease also known as bovine spongiform encephalopthy in cattle that cause by a misfolded protein i.e. prion .
Unisexuality of flowers prevents
Unisexuality of flowers prevents autogamy, but not geitonogamy. In self fertilisation , the male and, female gametes are derived from the same individual. Among plants, self fertilisation also called autogamy is common in many cultivated species, e.g., wheat and oats. However, self fertilisation is a form of inbreeding and does not allow for the mixing of genetic material; if it occurs over a number of generations it will result in offspring being less vigorous and productive than those resulting from cross fertilisation.
The C02 compensation point for C4-plants is
C02 compensation points of plants in a closed system depend on the ratio of C02 and 02. The compensation point for C4 plant is 0.0-5.0 ppm.
If the age distribution (percent individuals of a given age or group) is plotted for the population, the resulting structure is called a/an
Age distribution is percentage of individuals of a given age or age group. A population at any given time is composed of individuals of different ages. If age distribution is plotted for the population, the resulting structure is called as age pyramid.
Flowers are zygomorphic in
A flower that can be divided into two equal halves only in one plane is called as Zygomorphic flower, e.g.
Gulmohar, bean, Pisum, Cassia etc.
Select the option which shows correct matching of animal with there excretory organs and excretory product.
Salamander (amphibia; caudata) excretes urea with the help of kidneys.
The enzyme of EMP are located in
Glycolysis is a metabollic pathway that found in the cytoplasm of cells in all living organisms and all enzyme which take part in Glycolysis or EMP pathway found in Cytosol in plants.
The term ‘keel’ is used for special type of
A keel is a structure of the papilionaceous type of flower, made up of two petals loosely united along their edges
Part of the plant, which is cultured to obtain virus; Free clones is
Shoot tip is used to cultured to obtain virus free clones of the plants or other modified food or plants.
The genetically-modified (GM) brinjal in India has been developed for:
The genetically modified brinjal in India has been developed for insect resistance. Bt brinjal is a transgenic brinjal that is developed by inserting a crystal gene from the Bacillus thuringiensis into the brinjal’s genome. This process of insertion is accomplished using Agrobacterium mediated recombination.
Many cells function properly and divide mitotically even though they do not have
Plastids are responsible for the photosynthesis in various plants and few algae they do not envolve in division or fertilisation.
Which one of the following expanded forms of the following acronyms is correct?
The correct acronym of IUCN is International Union for Conservation of Nature and Natural resources.
Crossing over is the exchange of parts of chromosomes between two non-sister chromatids. Crossing over in diploid organism is responsible for
Crossing over or recombination is the exchange of chromosome segments between non-sister chromatids that is responsible for the recombination of genes in diploid organisms.
When huge amount of sewage is dumped into a river, its B.O.D. will
By dumping of huge amount of sewage, the oxygen levels are depleted, which are reflected in terms of BOD values of water.The number of microbes also increases tremendously and these also consume most of the oxygen. Thus BOD of the river water will increase.
Which one of the following is the most important for transfection in animal?
Transfection is the process of deliberately introducing genetic material, such as DNA and double stranded RNA into mammalian cells by retrovirus that contains an enzyme named reverse transcriptase.
Match the column-I with column-II and choose the correct option.
Incomplete dominance (discovered by Correns) is the phenomenon where the dominant allele does not completely express itself. The inheritance of flower colour in Antirrhinum sp. is a good example of incomplete dominance. Haemophilia is a sex linked recessive disease. It is a type of Mendelian disorder since its inheritance follows the principles of Mendelian genetics and can be traced in a family by pedigree analysis. Transforming principle was given by Griffith. Dihybrid cross is a cross when two allelic pair are used for crossing. Several dihybrid crosses were carried out in Drosophila to study genes that ware sex linked.
Which one is the component of ornithine cycle?
Carbon dioxide and ammonia undergo ornithine cycle in the liver cells. It takes place in five major steps. The extra proteins in the body are degraded by the process of deamination where the NH2 group is removed and it is converted into ammonium ions in the liver.
a) The ammonium ions combines with carbon dioxide in the presence of enzyme carbomyl phosphate synthase. It consumes two molecules of ATP.
b) Carbamoyl phosphate is converted to citrulline by enzyme ornithine transcarbamoylase.
c) A condensation reaction occurs between the amino group of aspartate and the carbonyl group of citrulline to form argininosuccinate. This reaction is ATP dependent and is catalyzed by argininosuccinate synthetase.
d) Argininosuccinate undergoes cleavage by argininosuccinase to form arginine and fumarate.
e) Arginine is cleaved by arginase to form urea and ornithine.
So, the correct answer is 'Ornithine, citrulline and arginine'.
Which of the following statement is correct about incomplete linkage?
(i) It is phenomenon in which more recombinants are produced in F2 generation.
(ii) More parental combination are produced in F1 generation.
(iii) Genotypes which are present in hybrid reappear in high frequency in F2 generation.
(iv) It is a phenomenon in which two chromosomes are linked.
Morgan carried out several dihybrid crosses in Drosophila to study genes th at were sex linked. The crosses were similar to the dihybrid crosses carried out by Mendel in peas. He observed that when two genes were grouped on the same chromosome, same genes are highly linked or associated and show low recombination. When the genes are loosely linked, they show higher recombination. Morgan attributed this due to the physical association or linkage of the two genes and coined the term linkage to describe this physical association of genes on a chromosome and the term recombination to describe the generation of non-parental gene combinations; His student Alfred Sturtevant used the frequency of recombination between gene pairs on the same chromosome as a measure o f the distance between genes and ’mapped’their position on the chromosome. Morgan hybridised yellow bodied and white eyed females with brown bodied and red eyed male (wild type) (cross-A) and inter-crossed their F1 progeny.
Ovulation takes place in a month during
Ovulation is the release of an egg from a woman's ovary. The day of ovulation differs from woman to woman, ovulation usually occurs between 14 and 16 days before menstrual period
In prokaryotes, the genetic material is
The Father has blood group AB and mother O. The child is supposed to have, which of the following blood groups?
Child is supposed to have either A or B blood group if father has AB and mother has O blood groups.
Animals with metameric segmentation, bilateral symmetry and closed circulatory system belong to phylum
Double stranded RNA is found in
Double stranded RNA containing virus is Reoviruses constituting the family Reoviridae, associated with upper respiratory infections, causes fever.
Match the scientists given in column-I with their work given in column-II and select the correct option.
F. Meischer discovered nuclein as an acidic substance present in nucleus. Griffith experimented with the smooth(S) and rough (R) strains of S. pneumoniae. Smooth strains of bacteria were virulent or pathogenic and cause pneumonia. Rough strains were non-parhogenic or avirulent. Hershey and Chase discovered that DNA is the genetic material of bacteriophage (virus which infects bacteria). Watson and Crick proposed the three dimensional structure of DNA based on X ray diffraction photographs of DNA taken by Rosalind Franklin and M H F Wilkins.
The bacteria Pseudomonas is useful because of its ability to
Pseudomonas is a gram negative bacteria it has ability to decompose a variety of organic compounds.
Code transfer for synthesis of polypeptide involves:
Surface architecture is studied b y the help of one of the following method
Phase contrast microscopy is a method to study about surface architecture of living or non livings.
In cockroach, the corpora allata is a/an
Volkmann’s canals are
Volkmann's canals are atomic arrangements in cortica bones which connect with Haversian canals Volkmann’s canals are; connective tissue, endosteum periosteum etc.
Both the crown and root of a tooth is covered by a layer of bony hard substance. It is called
Enamel is the hardest, glossy and mineralized surface of teeth. It covers both the crown and root of the tooth. It is a calcareous tissue.
Reproduction is the characteristic feature of livin g organisms. Which of the following cannot reproduce?
All living organism reproduce sexually or asexually but mules and worker bees can not reproduce because they do not have sex organs thus both are infertile.
Even when there is no air in it, human trachea does not collapse due to presence of
Metabolic reactions can be demonstrated outside of the body in cell free systems. An isolated metabolic reaction outside the body of an organism, performed in a test tube is
In a test tube an isolated metabolic living reaction takes place either body or cell, living nor non-living
What would happen if oxygen availability to activated sludge floes is reduced?
Sequence of DNA (non-coding) is known as
In genomics, Non-Coding DNA are the sequences of DNA that do not encode protein in the process of transcription called as Intron (a non-coding segment of a gene).
Diagram represents one cardiac cycle lasting 0.8 s and to the possible answers that follow it.
Which answer describes the events that occur during period X ?
Urea synthesis occurs in
The formation of urea from NH3 andC02 occurs in liver jj through ornithine cycle or Krebs Henseleit cycle.
Consider the following four statements (i - iv) about certain desert animals such as kangaroo rat.
(i) They have dark colour and high rate of reproduction and excrete solid urine.
(ii) They do not drink water, breathe at a slow rate to conserve water and have their body covered with thick hairs.
(iii) They feed on dry seeds and do not require drinking water.
(iv) They excrete very concentrated urine and do not use water to regulate body temperature.
Which two of the above statements for such animals are true?
The potential energy of water is referred as
Water potential is the potential energy of water per unit volume.
Water potential = Pressure potential + solute potential.
Thin filaments of skeletal muscle fibres contain
Which of the following is a 4 - Carbon compound?
Oxaloacetic add is a crystalline organic compound i.e. C4H405
Among which one of the following groups of chemicals, all are neurotransmitters?
Nissl granules are found in nerve cell and identified as one of the following structure
Nissl grunules are a large granular body found in neurons. These granules are of rough endoplasmic reticulum (RER) with rosettes of free ribosomes. It was named after franz Nissl, a German neuropathologist.
Match column-I with column-II and choose the correct option.
A: Golden rice is genetically modified rice that has been engineered to have high levels of β - carotene in it. It is a precursor of vitamin A, which gives it a characteristic golden colour. -B: Bt toxin is a pesticidal toxins (e.g.,CrylAb) produced by the soil bacterium Bacillus thuringiensis, which are lethal to com earthworms, potato, bugs and others. C:RNAi is a biological process in which RNA molecules inhibit gene expression, typically by causing the destruction of specific mRNA molecules. RNA interference (RNAi) technique has been devised to protect the plants from nematode is silenced by dsRNA produced by the host plant.
D: Rosie is the first transgenic cow (genetically modified cow). Rosie’s milk contains the human gene alpha-lactalbumin into their DNA. The extra gene may come from the same species or from a different species.
At retrogressive metamorphosis, the urochordate larva
Urochordate larva is called tadpole larva, because of its resemblance to a small tadpole of frog then it undergoes at retrogressive metamorphosis because of loss notochord, tail loss, experience reduction of nervous system to a visceral ganglion
The 24 hour (diurnal) rhythm of our body such as the sleep-wake cycle is regulated by the hormone
Which among the following type of DNA is present in bacterium E. coli?
Escherichia coli is a gram-negative facultatively anaerobic bacteria that contains double stranded circular DNA as a genetic material
Which of the following statements is false?
Golden rice is a
Golden Rice is a variety of Oryza Sativa produce through genetic engineering. Golden Rice is a precursor of Pro-vitamin A in the edible parts.
Egg is liberated from ovary in
Egg is liberated from the ovary (ovulation) at secondary oocyte stage when the meiosis II is arrested in secondary oocyte. It will be induced by the sperm.
Stroma in the chloroplasts of higher plants contain
Higher plants chloroplast stroma contains light-independent reaction enzymes i.e.
RUBISCO that is a poor enzyme.
Progestasert and LNG-20 are
An insect has jointed legs and chitinous exoskeleton and the number of legs are six that is 3 in pairs.
Select the correct statement from the ones given below with respect to dihybrid cross.
Linkage is the inheritance of genes of same chromosome together and capacity of these genes to retain their parental combination in subsequent generation. The strength of linkage between two genes is inversely proportional to the distance between the two. This means, two linked genes show higher frequency of recombination if the distance between them is higher and lower frequency if the distance is smaller.
Nerve impulse initiates with the movement of
When a neuron is not conducting any impule, i.e. resting, the axonal membrane is comparatively impermeable to sodium (Na+) ions. That initiates Nerve impulse.
Which ofthe following is the first thing that happens when a signal molecule acts on a target cell?
What is a keystone species?
A keystone species is a species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organisation and survival.
Damage to thymus in a child may lead to
The hormone which regulates sleep-wake cycle in man is
Melatonin is a hormone made by the pineal gland, a small gland in the brain, melatonin helps to control sleep and wake cycles in man.
An “Urn” shaped population age pyramid represents
In the process of photosynthesis, water molecule breaks during
The water molecules split into OH- and H+ ions. The OH- ions unite to form the water molecules again and release 02 and electron.
Match column-I with column-II and select the correct answer using the codes given below.
A 22 years student goes to his ophthalmologist. He has problem in reading books because he is not be able to contract his
An ophthalmologist is a specialist in medical and surgical eye problems. When someone goes tc ophthalmologist to take his problem like difficulty ir book reading that can not able to read a book. Doctor said that he has a problem in eyes' middle layer (vascular layer) and surrounds the lens the cause difficulty in contraction and reflextion is ciliary muscles.
Which one of the following pairs of structures is correctly matched with their correct description ?