A 40Ω electric heater is connected to a 200 V, 50 Hz mains supply. The peak value of electric current flowing in the circuit is approximately
The threshold wavelength of certain metal is 2000 Å , its work function is
A gun fires a bullet of mass 50 gm with a velocity of 30 m sec⁻1. Because of this gun is pushed back with a velocity of 1 m sec⁻1. The mass of the gun is
A parallel plate capacitor is filled by copper plate of thickness b. The new capacity will be
When a resistance of 2 ohm is connected across the terminals of a cell, the current is 0.5 amperes. When the resistance is increased to 5 ohm, the current is 0.25 amperes. The internal resistance of the cell is
What will be the ratio of de Broglie wavelengths of proton and α-particle of same energy
A photoelectric cell is illuminated by a point source of light 1 m away. When the source is shifted to 2 m then
What is increased in a step-down transformer
The curve drawn between velocity and frequency of photon in vacuum will be a
Gases begin to conduct electricity at low pressure because
The current passing through a coil of 5 H is decreasing at the rate of 2 A/s. The emf developed in the coil is
If the flux of magnetic induction through a coil of resistance R and having N turns changes from φ 1 to φ 2 , then the magnitude of the charge that passes through this coil is
A coil of inductances 300mH and resistance 2 Ω is connected to a source of voltage 2V. The current reaches half of its steady state value in
The capacitance of a parallel plate capacitor is 10 μF when distance between its plates is 8 cm. If distance between the plates is reduced to 4 cm, its capacitance will be
If the distance between the plates of a parallel plate condenser is halved and the dielectric is doubled, then its capacity increases by
In an electromagnetic wave, the electric and magnetising fields are 100 Vm-1 and 0.265 Am-1. The maximum energy flow is
S = E0 X H0
E0 = 100 Vm-1, H0 = 0.265 Am-1
∴ S = 100 X 0.26 = 26.5 Wm-2
Two masses of 1 gm and 4 gm are moving with equal kinetic energies. The ratio of the magnitudes of their linear momentum is
If the unit of force and length be each increased by four times, then the unit of energy is increased by
The meniscus of a liquid contained in one of the limbs of a narrow U-tube is held in an electromagnet with the meniscus in line with the field. The liquid is seen to rise. This indicates that the liquid is
An electric kettle takes 4A current at 220 V . How much time will it take to boil 1 kg of water from temperature 20ºC ? The temperature of boiling water is 100ºC.
At the magnetic poles of the earth, a compass needle will be
A uniform plank of Young's modulus Y, is moved over a smooth horizontal surface by a constant horizontal force F. The area of cross-section of plank is A. The compressive strain on the plank in the direction of the force is
A person sitting in an open car moving at constant velocity throws a ball vertically up into air. The ball falls
The ages of most ancient formations are estimated by
A mass m = 100 gms is attached at the end of a light spring which oscillates on a frictionless horizontal table with an amplitude equal to 0.16 metres and time period equal to 2 sec. Initially the mass is released from rest at t = 0 and displacement x = - 0.16 m. The expression for the displacement of the mass at any time (t) is
Standard equation for given condition
x = a cos 2π /Tt
⇒ x = - 0.16 cos (πt)
[As a = - 0.16 meter, T = 2 sec]
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): When a massive projectile collides with a lighter stationary target then maximum speed of target is twice that of projectile.
Reason(R): It is explained by the momentum and energy conservation.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): A falling ball is attracted by the earth, because of which velocity of the ball goes on increasing in the downward direction. The ball also attracts the earth with same force but velocity developed in earth is negligible.
Reason(R): Momentum of ball and earth system is conserved.
Since the mass of the earth is infinitely large compared to that of the ball, hence velocity developed in the earth is negligible
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): The maximum frequency of the photon produced by the union of a positron and an electron is 1.2 x 1020Hertz.
Reason(R): In electron-positron collision, both are annihilated and the total mass is converted into γ-photon(energy).
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): For stable equilibrium, Force has to be zero and potential energy should be minimum.
Reason(R): For equilibrium, it is not necessary that the force is not zero.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): When static friction is involved mechanical energy is not conserved.
Reason(R): Friction is non conservative force.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Cross-sectional area of the water pouring out of a tap decreases as the height from the ground decreases.
Reason(R): Work done by gravity reduces the cross-sectional area.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): In pure rolling motion, net work done by friction is zero.
Reason(R): Sum of translational work done by friction and rotational work done by friction is zero.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): By roughening the surface of glass sheet its transparency can be reduced.
Reason(R): Glass sheet with rough surface absorbs more light.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): The saturation current increases as the intensity of light increases.
Reason(R): The number of electrons emitted increases.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): There are 9 base units in SI
Reason (R) : Radian and steradian are base units
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): A galvonometer is said to be sensitive if a small current through it produces a small deflection.
Reason(R): Current sensitivity = (NAB)/c (symbols have their usual meaning).
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): A potentiometer having 10 wires is more accurate than the potentiometer having 1 wire.
Reason(R): Potential gradent of 10-wire potentiometer is much less.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Study of Fraunhofer lines in the spectrum of sun led to the discovery of hydrogen.
Reason(R): Fraunhofer lines are dark lines in the continuous solar spectrum.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Kirchoff's loop law represents conservation of energy.
Reason(R): If the sum of potential changes around a closed loop is not zero, unlimited energy could be gained by repeatedly carrying a charge around a loop.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): When a body is projected with velocity v = v0 (where v0 is orbital velocity) then path of the projectile is circular.
Reason(R): Gravitational force between body and the earth provides the centripetal force.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Refractive index of a material depends on the frequency of the light
Reason(R): Incoming e.m. wave applies an electric field and polarises it, contributing to (∈) permittivity of the medium, depending on its frequency.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): When photons of energy hv fall on a photo-sensitive metal surface(work function hv0), The kinetic energy of all the electrons emitted hv-hv0.
Reason(R): If the energy of the photon aborbed by the electron is less than the work function of the metal, then the electron will not be emitted.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Base of a mountain does experience a shearing stress-resulting in a flow.
Reason(R): Non-uniform compression due to the rocks at the top is responsible for the shearing stress.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Size of U235 is not essential for the phenomenon of nuclear fission.
Reason(R): Chain reaction takes place in nuclear fission.
If a force is applied on a body and it moves with a velocity ν, the power will be
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): The resistivity of a semiconductor increases with temperature.
Reason(R): The atoms of semiconductor vibrate at larger amplitude at higher temperature, thereby increasing resistivity.
A satisfactory photographic print is obtained when the exposure time is 10 seconds at a distance of 2 m from a 60 Cd lamp. The time of exposure required for the same quality print at a distance of 4 m from a 120 Cd lamp is
A ball is projected upwards from the top of tower with a velocity 50 ms⁻1 making an angle 30º with the horizontal. The height of the tower is 70 m. After how many seconds from the instant of throwing will the ball reach the ground?
A ray of light is incident on one of the refracting faces of an equilateral prism, at an angle of incidence 48º , in the minimum deviation position. The angle of deviation produced by the prism is
A telescope consists of two thin lenses of focal lengths 0.3 m and 3 cm respectively. It is focused on moon which subtends an angle of 0.5º at the objective. Then, the angle subtended at the eye by the final image will be
The electrical circuit used to get smooth dc output from a rectifier circuit is called
In a junction diode, the holes are due to
An electric bulb is designed to draw power P0 at voltage V0. If the voltage is V it draws a power P. Then
The S.I. unit of radioactivity is
Length, breadth and thickness of a block of wood are measured and following results are obtained. These are l=(25.120.01) cm, b=(20.15
0.01)cm, t=(15.28
0.01) cm. The percentage error in the volume of the block is
In Young's double slit experiment, the width of the fringes obtained with light of wavelength 6000 Angstrom is 2.0mm. The fringe width, if the entire apparatus is immersed in a liquid of refractive index 1.33, will be
Huygen's wave theory of light can not explain
In Young's experiment of double slit, the intensity of central bright band is ---- times the individual intensities of the interfering waves
A uniform chain of length L and mass M is lying on a smooth table and one third of its length is hanging vertically down over the edge of the table. If g is acceleration due to gravity, the work required to pull the hanging part on to the table is
Which of the following is the second most abundant element in the earth's crust?
Which of the following is the best example of an ideal black body
Mild oxidation of glycerol with H₂O₂/FeSO₄ gives
Heterolytic fission of a covalent bond in organic molecules gives
Which is correct statement about proton?
The catalyst used in Friedel Craft's reaction is
In benzene all the C ― C bonds have the same length because of
Carbon atoms in benzene molecule are inclined at an angle of
Which of the following gas changes lime water in milky colour?
In graphite, the electrons are
Covalent compounds have low melting points because
For a chemical reaction A → B, it is found that the rate of reaction doubles when the concentration of A is increased four times. The order in A for this reaction is
The first order rate constant for the decompositions of N₂O₅ is 6.2 x 10-4 sec⁻1 The t1/2 of decomposition is
An ideal gas heat engine operates in Carnot cycle between 227ºC and 127ºC. It absorbs 6 x 104 cals of heat at higher temp. Amount of heat converted into work is
= 4.8 x 104 cals
∴ W = Q1 - Q2 = 6 x 104 - 4.8 x 104
= 1.2 x 104 cals
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Borazine is called inorganic benzene.
Reason(R): Borazine has structural similarity with benzene.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Electronegatively of C in C2H6 and C2H2 is same.
Reason(R): Carbon in ethane is sp3 hybridised whereas in ethyne it is sp-hybridised.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): The atomic and ionic sizes of lanthanides decrease with increase of atomic number.
Reason(R): Successive addition of electrons into 4f orbital provides strong screening effect.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): A catalyst enhances the rate of a reaction.
Reason(R): The energy of activation of the reaction is lowered in presence of a catalyst.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Presence of acids and bases activates carbonyl compounds for reaction.
Reason(R): Carbonyl compounds possess positive and negative centres and provide seat for electrophilic and nucleophillic attack.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Phenols cannot be converted into esters by direct reaction with carboxylic acids.
Reason(R): Electron withdrawing groups increase the acidity of phenols.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Lime water turns milky when the gas liberated from an acidified carbonate solution is passed into it.
Reason(R): The liberated carbon dioxide reacts with lime water to give calcium bicarbonate as the precipitate.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Aluminium is most abundant element in the earth crust.
Reason(R): Aluminium mainly exists as oxide in nature.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Heat energy is completely transformed to work during isothermal expansion of gas
Reason. (R): During isothermal process, the changes in internal energy of a gas due to decrease in pressure is nullified by the changes due to increase in volume.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Lithium differes from rest of the members of group I.
Reason(R): Li has small size and forms covalent compounds in comparison to other group I metals.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): [Cr(NH3)6]3+ is paramagnetic
Reason(R): [Cr(NH3)6]3- shows d2sp3 hybridi-sation, with three unpaired electrons.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Cycloheptatrienyl cationshows unusual stability.
Reason(R): All unsaturated compounds having (4n + 2)π electrons show unusual stability.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Malachite is a triphenyl methane dye.
Reason(R): It contains -N = N groups.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Electron affinity of N is more than that of P.
Reason(R): Nitrogen is smaller than P.
Electron affinity of N is less than that of P, because the added electrons will be accomodated to smaller sizes 2p-subshell, which already housing one electron.
This results in inter-electronic repulsions and lowering of EA
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): HC ≡ C- is more stable than H2C = C-.
Reason(R): HC ≡ C-, has more s-character than H2C = C-.
HC ≡ C- has 50% s-character and H2C = C- has 33% s-character.
Stability of carbanions increases with an increase in the s-character at the carbanion.
So HC ≡ C- is more stable than H2C = C-
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Benzaldehyde is more reactive than ethanol towards nucleophilic attack.
Reason(R): All the carbon atoms of benzaldehyde are sp2-hybridized.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): In colloidal solution elevation in b.p. and depression in freezing point is very small.
Reason(R): Colloidal particles have high average molecular masses of colloidal particles, they give very low mole fraction in colloidal solution.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): Hydrogen gas cannot be prepared in laboratory.
Reason(R): Hydrogen gas of high purity is obtained by electrolysing warm aqueous barium hydroxide between nickel electrodes.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): NF3 is a weaker ligand than N(CH3)3
Reason(R): NF3 ionises to F- ions in aqueous solution
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the Statements carefully and mark the correct answer-
Assertion(A): The tendency of alkyl halides to undergo dehydrohalo-genation in Williamson's synthesis is tert > sec > prim.
Reason(R): The order of stability of carbocation is prim > sec > tert.
In an experiment set up for the measurement of e.m.f. of a half-cell using a reference electrode and a salt bridge, when the salt bridge is removed the voltage
In the chemical reaction,
Ag₂O + H₂O + 2e⁻ → 2Ag + 2OH⁻
One mole of Argon gas will have least density at
Strongest bond is in between
Which of the following represents calcium chlorite?
Fire extinguishers contain H₂SO₄ and
Which of the following has lowest thermal stability?
Among the following NaOH, Ca(OH)₂, KOH and Zn(OH)₂. The weakest base is
Action of water or dilute minerals acids on metals can give
pH of a solution produced when an aqueous solution of pH = 6 is mixed with an equal volume of an aqueous solution of pH = 3 is about:
When rain is accompanied by thunderstorm, the collected rain water will have a pH value
If pH values of P, Q, R and S are 9.5, 2.5, 3.5 and 5.5 respectively, then the strongest acid is
The pH of the solution, produced when an aqueous solution of pH 5 is mixed with an equal volume of an aqueous solution of pH 3, is
From which of the following tertiary butyl alcohol is obtained by the action of methyl magnesium iodide?
Which of the following is a method of converting a ketone into hydrocarbon ?
Which of the following compounds can react with the Lewis base Cl− in a Lewis acid-base reaction?
Which gives more stable product ?
Most stable alkene is :
Which type of glass has a property to cut off ultra-violet rays?
Which is not the resonance structure of aniline?
Potassium crystallizes with a
The relative lowering of vapour pressure for a solution is equal to
At a particular temperature, the vapour pressure of two liquids A and B are respectively 120 and 180 mm of mercury. If 2 moles of A and 3 moles of B are mixed to from an ideal solution, the vapour pressure of the solution at the same temperature will be
The formula of metal chloride is MCl3. It contains 20% of metal. The atomic weight of metal is approximately
Hydrochloric acid solution A and B have concentration of 0.5 N and 0.1 N respectively. The volumes of solutions A and B required to makes 3 litres of 0.2 N HCl are
Isomers whose molecular structures are non-superimposable mirror images of each other are called:
Passivity of iron is due to formation of
Starting from outside, the layer present in intestinal wall, are
Housefly feeds on sugar by
Flightless bird cassoway is native of
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): Phytochrome exists in two forms - Pr and P fr .
Reason (R): Pr form stimulates and P fr form inhibits flowering.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): Guard cells are specialised epidermal cells.
Reason (R): Stomata are found in the epidermis of leaves.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): Deforestation is one main factor contributing to global warming.
Reason(R): Besides CO2, two other gases methane and CFCs are also included under green house gases.
Deforestation increases atmospheric CO2 content by releasing carbon stored in organic matter and reduced primary productivity . So deforestation is one of the main factors contributing to global warming other than green house gases. the various green house gases are CO2 ,CH4,CFCs and nitrogen oxide N2O. Due to increase of CO2 concentration, the absorption of heat radiation also increase thus increasing the temperature.Thisincrease in temperature may cause melting of Glaciers and polar ice caps, which is called global warming. This melting of glaciers and polar ice results in raising the sea level. Actually these green house gases absorb infra red radiations of the sun like glass and thus traps the heat and does not allow it to radiate back to the space. They instead radiate the heat back to earth, thus causing increase in temperature.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): The main function of suspensor is to provide nutrition to embryo.
Reason (R): It is attached to embryo by hypophysis.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): Amber codon is a termination codon.
Reason(R): If in m-RNA, a termination codon is present, the protein synthesis stops abruptly whether the protein synthesis is completed or not.
There are three codons UAA, UAG and UGA which are designated as termination codons. UAA (also known as ochre), UAG (also known as amber) and UGA (also known as opal) are three codons which whenever present in mRNA, would bring about termination of polypeptide chain which would then be released from ribosome. m-RNA has a "termination codon" region which consists of UAA, UAG or UGA.So Amber alone can not terminate the process of protein synthesis.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): In hemianatropous ovule, the funicle lies parallel to body of ovule.
Reason (R): Here, body of ovule has rotated by 90º
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): Leaves of C4 plants show Kranz anatomy.
Resaon (R): C4 plants possess two types of chloroplast.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): Severe Acute Respiratory Syndrome (SARS) originated in China.
Reason(R): China is the most poulated country of the world.
Severe Acute Respiratory Syndrome (SARS) a severe acute type of pneumonia caused by metapneumo virus was first reported in China.
Though China is the most populated country of the world it is not directly responsible for the origin of SARS. The killer pneumonia virus is responsible for SARS origin.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): Leaves are present in different planes of branch.
Reason (R): A branch possesses leaf at terminal position.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): Vascular cambium is considered as lateral meristem.
Reason(R): It gives rise to lateral shoots.
Vascular cambium gives rise to xylem tissue on the inside and phloem on the outside.
Lateral buds contain meristematic cells that give rise to lateral shoots or fruit.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): Rhoeo leaves contain anthocyanin pigments in epidermal cells.
Reason(R): Anthocyanins are accessory photosynthetic pigments.
Anthocyanin is a colouring pigment of certain higher plants that imparts a bluish or reddish colour.
Rhoeo leaves contain anthocyanin pigments in epidermal cells.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): A network of food chains existing together in an ecosystem is known as a food web.
Reason(R): An animal like kite cannot be a part of a food web.
The process of transfer of energy from producers through a series of organisms, which means from primary consumers to secondary consumers to tertiary consumers by process of eating and being eaten constittue a food chain.Example Grassland Ecosystem.
Food cahins can never occur independently in ecosystem but various food chains are inter-connected with each other forming an interlocked system known as food web. In grassland ecosystem food chains may be- Grass-Rabbit-Hawk/Kite or Grass-Mouse-Snake-Kite/Hawk or Grass- Grasshopper-Lizard-Kite/Hawk. So the food web will always incude kite.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): Hair cells on the basilar membrane (organ of Corti) are responsible for hearing.
Reason(R): Pressure waves, which begin at the oval windows, cause the basilar membrane to vibrate so that the cilia of the hair cells touch the tectorial membrane. This causes the hair cells to initiate nerve impulses, which are carried by the auditory nerve to the brain.
Hair cells on the basilar membrane is responsible for hearing. In the cochlear duct of the internal ear, the basilar papila forms a basilar membrane with hair cells constituting an organ of Corti, the fibres are embedded in a tectorial membrane lying above the organ of Corti which is sensitive to vibrations of high freequency.
Pressure waves at oval window causes vibration in basialr membrane, which in turn creates vibrations in the cilia of hair cells touching tectorial membrane. This vibration initiates nerve impulse in auditory nerve, which sends this impulse to the brain.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): The major end products of photosynthesis is hexoses.
Reason (R): Free glucose is not present in higher quantity.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): The globular embryo is considered as proembryo.
Reason (R): The plumule, radical and cotyledons start differentiation during heart stage of embryo.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): A cell membrane shows fluid behaviour.
Reason(R): A membrane is a mosaic or composite of diverse lipids and proteins.
Singer and Nicolson in 1972 gave the fluid-mosaic model which descibes the structure of the cell membrane. According to them the cell membranes are considered to be quasifluid structures in which the lipids and proteins are in mosaic manner. The lipid protein association is hydrophobic according to this model. The fluidity of the membrane is the result of this hydrophobic interaction.
In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R). Read the statements carefully, and mark the correct answer.
Assertion(A): A single strand of m-RNA is capable of forming a number of different polypeptide chains.
Reason(R): Termination codons occur in m-RNA.
Messenger RNA (mRNA) is a molecule of RNA encoding a chemical "blueprint" for a protein product. mRNA brings instructions from the DNA for the formation of particular type of polypeptide. The instructions are present in the base sequence of its nucleotides. mRNA has methylated region at the 5'terminus. It functions as a cap for attachment with ribosome. Cap is followed by an initiation codon (AUG) either immediately or after a small noncoding region. An mRNA may specify only a singled monocistronic while the latter is known as polycistronic.
Three of the 64 codons are UAG (amber), UAA (ochre) and UGA (opal or umber), they bring about termination of polypeptide chain synthesis and are called termination codons or stop codons.
In the following questions, a statement of Assertion (A) is given followed by a corresponding Reason (R) just below it. Read the statements carefully and mark the answer-
Assertion (A): Nuclear membrane reappears during metaphase.
Reason (R): It is formed by vesicles of the ER.
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer.
Assertion(A): There is a need to understand the ecological principles.
Reason (R): One studies the interactions between organisms and their environment in ecology.
Cellulose occurs in
In the following question, a Statement of Assertion (A) is given followed by a corresponding Reason(R) just below it. Read the Statement carefully and mark the correct answer-
Assertion(A): A total of 10 NADH 2 and 2FADH 2 molecules are formed in aerobic respiration.
Reason (R): NADH 2 and 2FADH 2 help in formation of 34 ATP molecules.
Which one is not true ?
Blood with a high oxygen concentration can be found in both the
The Indian soils are generally poor in
In succulents, respiration quotient is less than one due to
Azolla is used as a biofertilizer, because it
Cystic duct arises from
Azadirachtin, a common constituent of mosquito repellant coils comes from
Bipedal locomotion is advantageous because it
What is true of tRNA ?
Which one is correctly matched with its specificity for an amino acid, start or stop in protein synthesis
Back cross involves :
Colour blindness is disease in which the factor is usually transmitted to children by woman. It is because the factor is located on
An Rh⁻ individual receives Rh⁺ blood. The recipient becomes
A person with antigen 'B' in RBC and antibodies 'a' in the plasma belongs to the blood group
Blue-green algae are placed in which of the following division ?
Elongated peduncle bearing pedicellate flowers continuously in acropetal order is
Antiboides are
Binding of antigen to antibody is through
In photosynthesis, energy from light reaction to dark is transferred in the form of
An essential process connected with photosynthesis is
The main difference in Gram (+) ve and Gram (-) ve bacteria resides in their
Cerebellum of brain is concerned with
Who first of all indicated that water is electron donor in photosynthesis ?
One of the following vaccines is not made from recombinant DNA technology
Anatomically Jute fibres are
Primary constituents of photochemical smog are
Triple fusion involves fusion of