The impedance of a circuit consists of 3 ohm resistance and 4 ohm reactance. The power factor of the circuit is
Photons of energy 1eV and 2.5 eV successively illuminate a metal whose work function is 0.5 eV. The ratio of the maximum speeds of the electrons emitted will be
A parallel plate capacitor is first charged and then a dielectric slab is introduced between the plates. The quantity that remains unchanged is
When a capacitor is disconnected from the battery, then the charge Q remains unchanged
A rifle bullet loses 1/20th of its velocity in passing through a plank. The least number of such planks required just to stop the bullet is
At what temperature, the resistance of a copper wire will become three times its value at 0ºC ? (Temperature coefficient of resistance for copper = 4 x 10⁻3per ºC)
Photon of 5.5eV energy fall on the surface of the metal emitting photoelectrons of maximum kinetic energy 4.0eV. The stopping voltage required for these electrons are
Choke coil works on the principle of
In an L-R circuit, time constant is that time in which current grows from zero to the value
Which of the following statements is correct ?
Quantum theory of light gives concept of
In photoelectric emission the number of electrons ejected per second
A 100 mH coil carries a current of 10 A. The magnetic energy stored in the coil is
In an oscillating LC circuit the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electric and magnetic fields is
If the unit of force and length be each increased by four times, then the unit of energy is increased by
Maxwell's equation describe the fundamental laws of
If a positive charge is shifted from a low potential region to a high potential region, then the electric potential energy of the system
The enegy stored in wound watch spring is
A particle of charge -q and mass m moves in a circle of radius r around an infinitely long line charge of linear charge density + λ . Then time period will be:(Where
One feels hotter at the top of a flame than the sides because of
Time period of oscillation of a magnet is 2 sec. When it is remagnetised so that its pole strength is 4 times, its period will be
If t1 and t2 are time taken by two different coils for producing same heat with same supply, then the time taken by them to produce the same heat when connected in parallel will be
A wire of length L and radius a rigidly fixed at one end. On stretching the other end of the wire with a force F, the increase in it length is l. If another wire of same material but of length 2L and radius 2a is stretched with a force 2F, the increase in its length will be
Magnetic dipole moment is a vector quantity directed from
A light spring balance hangs from the hook of the other light spring balance and a block of mass M kg hangs from the former one. Then the true statement about the scale reading is
The radioisotope, tritium (3H₁) has a half-life of 12.3 years. If the initial amount of tritium is 32 mg, how many miligrams of it would remain after 49.2 years ?
A hollow sphere is filled with water through a small hole in it. It is hung by a long thread and made to oscillate. As the water slowly flows out of the hole at the bottom, the period of oscillation will
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): Any internal forces in the system are included while considering force for Newton's second law of motion.
Reason(R): The force in the law stands for the net force on the system.
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): Sound produced in air is not heard by a person deep inside water .
Reason(R): Most of the sound is refracted from air to water and very less is reflected .
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): Decay of radioactive substance is rapid in the beginning.
Reason(R): At any instant the rate of decay of radioactive is proportional to the number of atoms present at that instant.
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): All processes in which pressure and volume are proportional, take place at constant temperature.
Reason(R): Work done in a thermodynamical process is path dependent.
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): Length, mass and velocity can act as fundamental quantities in a system of units; mass, time and velocity also can but length, time and velocity can't
Reason (R) : The fundamental quantities are those quantities which do not depend on other quantities in the system
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 body of mass m1 collides head on elastically with another stationary body of mass m2. After the collision, velocity of mass m2 is maximum, when m1<<m2.
Reason(R): Velocity of second body is always maximum, when its mass m2 is greater than mass of the hitting body.
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 combination Y = sin ωt + cos2ωt is not a simple harmonic function even though it is periodic.
Reason(R): All periodic functions satisfy the relation Y = -kY or
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 parallel plate capacitor is connected across battery through a key. A dielectric slab of constant K is introduced between the plates. The energy stored becomes K times.
Reason(R): The surface density of charge on the plates remains constant or unchanged.
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): Voltmeter is connected in parallel to an electric circuit.
Reason(R): So that whole current pases through it .
The volmeter measures the potential difference between two points of a circuit.
Hence it is connected in parallel to those points
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 red object appears dark in yellow light.
Reason(R): The red colour is scattered 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): Vapour is condensed in the form of drops on ions, not on air molecules.
Reason(R): Molecules are very small is size.
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): If a pin-sited hole is created in an otherwise uniform spherical shell of definite mass and radius, the gravitational field at a point just out side and close to hole is zero
Reason(R): In the given case, the field just inside and just outside (along the hole) must be same the field inside is zero, hence the field outside should also be 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): Gravitational potential of the earth at every place is negative.
Reason(R): Everybody on earth is bound by the attraction of earth.
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): Moment of inertia depends on the distribution of mass
Reason(R): Moment of inertia is a scalar quantity.
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 wire has a resistance of 12Ω. It is bent in the form of a circle. The effective resistance between two points on any diameter is 6Ω.
Reason(R): Equivalent resistance between two points on any diameter is in series.
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): Alpha decay and beta decay are accompanied by gamma decay.
Reason(R): On α and β decay, the daughter nucleus is in excited state. It returns to ground state by gamma emission.
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 closed pipe produces only old harmonics, while an open pipe produces only even harmonics.
Reason(R): Closed end of the pipe reflects the longitudinal wave like a rigid boundary while the open end reflects the longitudinal wave like a free boundary .
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): Nuclear fission is the basis of a hydrogen bomb.
Reason(R): Fission bomb is much more powerful and destructive than the fission bomb.
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 pair production, energy of γ ray is greater than 1.02 MeV.
Reason(R): In pair production, energy is converted into mass.
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): Gases, in general , are poor conductors of electricity .
Reason(R): At the same temperature and pressure equal volumes of all gases contain equal number of molecules.
An electric motor creates a tension of 4500 newton in a hoisting cable and reels it in at the rate of 2 m/sec. What is the power of electric motor
A particle of mass m is projected with the velocity ν making an angle of 45º with the horizontal. The magnitude of the angular momentum of the particle about the point of projection when the particle is at its maximum height is (where g = acceleration due to gravity)
Critical angle for light going from medium (i) to (ii) is θ. The speed of light in medium (i) is ν. Then speed in medium (ii) is
When a glass lens with n = 1.47 is immersed in a trough of liquid, it looks to be disappeared. The liquid in the trough could be
A spherical air bubble is embedded in a piece of glass. For a light ray passing through it, it behaves like a
The potential barrier, in the depletion of layer, is due to
When the electrical conductivity of a semiconductor is due to the breaking of its covalent bonds, then the semiconductor is said to be
Which physical quantities have the same dimension
When an electric current flows in a conductor, its temperature
The SI unit of universal gas constant (R) is
Which of the following property of light waves is not observed in sound waves?
When a source of light is receding away from an observer, then the spectral lines will get displaced towards
The sun is rotating about is own axis. The spectral lines emitted from the two ends of its equator, for an observer on the earth, will show
A body of mass m is moving in a circle of radius r with a constant speed v. The force on the body is and is directed towards the centre. What is the work done by this force in moving the body over half the circumference of the circle
Work done by the centripetal force is zero
Absolute alcohol (100% alcohol) is prepared by distilling rectified spirit over
Which of the following has the smallest heat of hydrogenation per mole?
Conjugated double bond being most stable has the least heat of hydrogenation
The volume in litres of CO2 liberated at STP when 10 grams of 90% pure limestone is heated completely is
Limestone (CaCO3) has a molar mass of = 100 g/mol
So, 10 gm of 100% pure CaCO3 would = 10 gm of CaCO3
90% pure CaCO3 means, each 10 gm of sample will have, = x 10 = 9 gm CaCO3
So, number of moles of CaCO3 = given mass/ molar mass = = 0.09
Now, we have the reaction,
CaCO3 → CaO + CO2
When 1 mole of CaCO3 yields 1 moles of CO2
0.09 moles of CaCO3 will yield 0.09 moles of CO2
1 mole of CO2 = 22.4 liters (at STP)
So, total volume = 22.4 x 0.09 = 2.016 liters
The most reactive among the following towards sulphonation is
The oxidation of toluene with air in the presence of V₂O₅ catalyst, gives
Which reaction sequence would be best to prepare 3-chloro-aniline from benzene?
Freon is used as a
which of the following shows electrical conduction?
Pi bond is formed by the overlapping of
A catalyst
A reaction involving two different reactants can never be
Heat exchanged in a chemical reaction at constant temperature and pressure is called
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): Boric acid acts as a strong acid in presence of catechol.
Reason(R): Boric acid does not act as a proton donor but behaves as a Lewis acid.
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): Magnetic moment value for copper (II) acetate is less than that for one unpaired electron.
Reason(R): Interaction between unpaired electrons belonging to different copper atoms occurs via bridging acetate group.
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): Production of electricity by thermal plants is a very efficient method.
Reason(R): In thermal plants, the chemical energy (heat of combustion) of fossil fuels (coal, gas or oil) is used to produce electricity.
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): sp3 orbital forms the longest and sp orbital forms the shortest bond.
Reason(R): sp3 orbital the longest and sp orbital forms the shortest bond.
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): Aspirin is a well known analgesic.
Reason(R): Chemical substances used for relieving pain are called analgesics.
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): Starch contains 20% amylose and 80% amyplopectin.
Reason(R): In starch , the glucose units are linked by β-linkages .
The glucose units are linked to one another by α-glycosidic linkages in starch
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): Potassium is not obtained by the eletrolysis of fused KCl.
Reason(R): Potassium vapourises at the melting point of KCl.
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 CaCl crystal, the co-ordination number of Cs+ ion is 8.
Reason(R): Ci-ion in CsCl adopt bcc type of packing.
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): Second ionisation energy is always smaller than the first ionisation energy .
Reason(R): It is difficult to remove a negatively charged species from an already positively charged species.
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): SiO2 exists in both crystalline and amorphous form.
Reason(R): Quartz is crystalline form and obisdian is its amorphous form.
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): Nitrogen is unreactive at room temperature but becomes reactive at elevated temperatures or in presence of a catalyst.
Reason(R): In nitrogen molecule there is extensive delocalisation of 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): Nitriding is a process of heating steel in an atmosphere of nitrogen.
Reason(R): Steel becomes brittle after nitriding.
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 titration of Na₂CO₃ and HCl phenolphthalein can be used as indicator.
Reason(R): Phenolphthalein can be used as indicator in acid base titrations.
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): Water is not known to react with metal salts.
Reason(R): Water occupies the interstitial sites in the crystal lattice of some compounds.
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): bcc arrangement is less closely packed than ccp arrangement .
Reason(R): In ccp arrangement, the two atoms at the corners of the unit cells are touching each other whereas in bcc arrangement, they are not touching each other.
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 acidic medium equivalent weight of K₂Cr₂O₇ equals to 294 same as that of molecular weight.
Reason(R): In acidic medium K₂Cr₂O₇ does not observe any change.
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): Alkylation of benzene by Friedal-Craft reaction gives polyalkylated compounds.
Reason(R): The ring gets activated for further substitution after the introduction of one alkyl group.
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): Aqueous solution of phenol is called as carbonic acid.
Reason(R): Increasing order of acidity of phenols is m-nitrophenol>o-nitrophenol>p-nitrophenol.
Aqueous solution of phenol is known as carbolic acid
Electron withdrawing groups such as bond -NO2, -CN, - X increase the acidity of phenol.
The increase is more when electron withdrawing groups are at o-and p-positions than at m-position. i.e.,
p - nitrophenol > o-nitrophenol > m-nitrophenol
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 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): Methanol is stronger acid than water.
Reason(R): Among monohydric aliphatic alcohols methanol is the strongest acid.
Faraday constant
The current in a given wire is 1.8 A. A charge passed through the wire in 1.36 minutes is
Air at sea-level is dense ,this is practical application of
A combustile gas is liberated when caustic soda solution is heated with
Caesium oxide will be
The strongest reducing agent out of Na, K, Rb and Cs is
A chloride dissolves appreciably in cold water. When placed on a platinum wire in Bunsen flame no distinctive colour is noted, which cation would be present?
Which of the following is not a Lewis acid?
Which of the following is not linear?
The boiling point of water is exceptionally high because
The pH of solutions A, B, C and D are respectively 9.5, 2.5, 3.5 and 5.5. The most acidic solution is
Species acting both as Bronsted acid and base is
Ketones (R₁COR₂);R₁═R₂═alkyl group, can be obtained in one step by
Which of the following reactant in the presence of AlCl₃ gives acetophenone?
which of the following solution is not buffer?
Conc.HNO3 formsinpresenceof:
In the following, electrophile is:
HO ― NO2
The addition of HBr to alkenes in the presence of peroxides is called :
In a face-centered cubic lattice, a unit cell is shared equally by how many unit cells?
Silicon combines with magnesium in an electric arc furnace between 2000K to 2500 k to produce
Which is not the resonance structure of aniline?
Which of the following is the second most abundant element in the earth's crust?
The normality of a 2.3 M sulphuric acid solution is
The average osmotic pressure of human blood is 7.8 bar at 37ºC. What is the concentration of an aqueous NaCl solution that could be used in the blood stream?
The depression of freezing point is directly proportional to
Which of the following compounds can show optical isomerism?
Cuprous ion is colourless while cupric ion is coloured because
If 0.5 mol of BaCl₂ is mixed with 0.2 mol of Na₃PO₄, the maximum number of mole of Ba₃(PO₄)₂ that can be formed is
2 mol of Na3PO4 reacts with 3 mol of BaCl2 to form 1 mol Ba3(PO4)2
∴ 0.2 mol of Na3PO4 reacts with 0.3 mol of BaCl2 to form 0.1 mol Ba3(PO4)2.
Thus,Na3PO4 is limiting reagent here.
Which of the following is superficial of the calf muscle ?
Which of the following belongs to class Insecta?
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): Glucokinase is present in liver and muscle cells.
Reason (R): Glucokinase phosphorylates all types of hexoses.
Best definition of birds is
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): When the ambient temperature is high and soil contains excess of water, the plants tend to lose water in the form of droplets from lenticels.
Reason(R): Root pressure regulates the rate of loss of water form lenticels.
When the ambient temperature is high and soil contains excess water, the rate of transpiration is increased i.e. loss of water takes place from leaves through stomata.
Lenticular transpiration is only 0.1% of the total transpiration. It however continues day and night because lenticels have no mechanism of closure. The lenticels connect the atmospheric air with the cortical tissue of stem through intercellular spaces present amongst the complementary cells. Root pressure regulates the rate of loss of water from the stomata in some plants.
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): Coconut has wide distribution along the seashores.
Reason (R): It is dispersed by water.
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): Mitochondria may store and release calcium when required.
Reason (R): In the presence of calcium, mitochondria phosphorylate no longer.
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): Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.
Reason(R): Eggs of most mammals, including humans, are of centrolecithal type.
In holoblastic cleavage the cleavage furrows bisect the entire egg, or in other words entire egg divides by each cleavage furrow in placental mammals having isolecithal or microlecithal egg the holoblastic cleavage produces blastomeres of equal or approximately equal size.
Centrolecithal eggs are found in insects and in some hydrozoa. Here yolk is concentrated at the centre of egg and the cytoplasm is present surrounding it. Meroblastic cleavage occurs in them.
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): Biotic community has higher position than population in ecological hierarchy.
Reason (R): Population of similar individual remains isolated in the community.
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): When six molecules of carbon dioxide participate in photosynthesis, 12 molecules of NADPH+H+ and 18 ATP are used up, forming one hexose molecule.
Reason(R): The photosynthetic light reaction results in the formation of ATP and NADPH2.
When six molecules of carbon dioxide enter Calvin Cylce, one hexose molecule is formed, whereas 18ATP and 12 NADPH+H+ molecules are used up.
The light reaction of photosynthesis results in the formation of ATP and NADPH2.
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): In the descending limb of loop of Henle, the urnie is hypertonic, while in ascending limb of loops of Henle, the urine is hypotonic.
Reason(R): Descending limb is impermeable to Na+, while ascending limb is impermeable to H2O.
The loop of Henle, also called the nephron loop, is a U-shaped tube that extends from the proximal tubule. It consists of a descending limb and ascending limb.The descending limb is permeable to water and noticeably less impermeable to salt, and thus only indirectly contributes to the concentration of the interstitium. As the filtrate descends deeper into the hypertonic interstitium of the renal medulla, water flows freely out of the descending limb by osmosis until the tonicity of the filtrate and interstitium equilibrate. Longer descending limbs allow more time for water to flow out of the filtrate, so longer limbs make the filtrate more hypertonic than shorter limbs.Unlike the descending limb, the ascending limb of Henle's loop is impermeable to water, a critical feature of the countercurrent exchange mechanism employed by the loop. The ascending limb actively pumps sodium out of the filtrate, generating the hypertonic interstitium that drives countercurrent exchange. In passing through the ascending limb, the filtrate grows hypotonic since it has lost much of its sodium content. This hypotonic filtrate is passed to the distal convoluted tubule in the renal cortex.
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): Haemophilia is a recessive sex linked disease.
Reason(R): Haemophilia occurs due to mutation of a structural gene on chromosome 15.
Haemophilia (also known as bleeder disease) is a popular example of sex linked inheritance in human beings. Haemophilia is either of two hereditary disorders in which the blood clots very slowly, due to a deficiency of either of two coagulation factors - haemophilia A, due to deficiency of factor VIII (antihaemophilic factor); or haemophilia B, due to deficiency of factor IX (Christmas factor). The patient may experience prolonged bleeding following any injury or wound, and in severe cases there is spontaneous bleeding into muscles and joints. Haemophilia is controlled by a sex-linked gene, which means that it is almost exclusively restricted to males; women can carry the disease - and pass it on to their sons - without being affected themselves. The genes encoding factors VIII and IX have been used in gene therapy trials for haemophilia.
Mutation of a structural gene on chromosome 15 is the molecular basis of Marfan syndrome. This disease is due to dominant mutation resulting in the production of abnormal form of connective tissues and characteristic extreme looseness of joints.
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): Agricultural output increased several tims after introduction of DDT.
Reason(R): DDT was the first insecticide used on a wide scale.
DDT or dichloro-diphenyl trichloroethane was the first important synthetic pesticide discovered in 1939 by a Swiss chemist Paul Muller. It was toxic to wide range of insect pests yet appeared to have low toxicity to mammals. It was persistent which means it do not break down rapidly in the environment, so that it did not have to be reapplied often. DDT was so effective at killing pests and thus boosting crops yield and was so inexpensive to make that its use quickly spread over the globe. Farmers used more and more DDT throughout the 1950 and 1960 to get an increased yield of crop.
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): Low annual rainfall occurs in deserts.
Reason (R): Deserts may be hot or cold.
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): Companion cells control the sieve tube cell activities.
Reason (R): Companion cells possess nucleus.
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): Study of biology requires basic knowledge of chemistry and physics.
Reason(R): Living organisms are made up of atoms and molecules which follow chemical and physical laws.
The field of biology is getting advanced day by day to such an extent that basci knowledge of physics, chemistry and other sciences is necessarily required.All the living organisms are made up of atoms and molecules which follow certain laws associated with them. Therefore it becomes essential to have the knowledge of chemical and physical sciences also.
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): In apomixis, the plants of new genetic sequence are produced.
Reason(R): In apomixis, two individuals of same genetic sequence meet.
Winkler defined apomixis as replacement of the normal sexual reproduction by asexual reproduction, without fertilization.Apomictically produced offspring are genetically identical to the parent plant.
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): Leucoplasts give rise to other types of plastids.
Reason (R): Chromoplasts do not get changed to other types of plastids.
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): Diabetes insipidus is marked by excessive urination and too much thirst of water.
Reason(R): Anti-diuretic hormone (ADH) is secreted by the posterior lobe of pituitary gland.
Anti-diuretic hormone (ADH) or vasopressin is a peptide hormone, synthesized in the hypothalamus and released by the posterior pituitary gland, that stimulates capillary muscles and reduces the flow of urine and increases its concentration. It is released in response to a fall in the water content of blood plasma and lead to an increase in the permeability to water of the distal and collecting tubules of the nephron. Deficiency or hyposecretion of ADH results in diabetes insipidus.
Diabetes insipidus is characterized by micturating dilute urine several times a dday which results in excessive thirst and dehydration.
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): Chloroplasts synthesise all protein which they require for photosynthesis.
Reason (R): Chloroplasts are semiautonomous and contain ribosomes.
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): Placenta bears ovules.
Reason (R): An ovary has one placenta.
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): Agrobacterium tumefaciens is popular in genetic engineering because this bacterium is associated with the roots of all cereal and pulse crops.
Reason(R): A gene incorporated in the bacterial chromosomal genome gets automatically transferred to the crop with which the bacterium is associated.
Agrobacterium tumefaciens is a gram negative , non-sporing, motile, rod-shaped bacteria closely related to Rhizobium It is found commonly around root surfaces. The region termed rhizosphere where it seems to survive by using nutrints from the root tissues. It infects only through the wound-site either naturally occuring or caused by transplanting of seeding and nursery stock.
It transfers DNA into plant genomes found in soil worldwide.Agrobacterium tumefaciens causes crown gall disease of a wide range of dicot plants especially members of rose family by transferring its own DNA into plant cells.But in laboratory, the ability to move all sorts of genes into plants has made the microbe the standard tool for investigating plant genetics and modifying crops.
In a man normal glucose conc. increases to 190 mg/100ml. Which of the following will occur?
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): Xylem and phloem are complex tissues.
Reason (R): Complex tissue is collection of different types of cells.
The highest blood pressure in the aorta occurs when the
Anaerobic process, after glycolysis, is called
Products of the liver include
Radio tracer techniques show that DNA is in
Flax fibers belong to
Germinating barley seeds are used in the production of
Triticale is the hybrid between wheat and
Which one is correctly matched with its specificity for an amino acid, start or stop in protein synthesis
Man was originated in which era?
Gene and cistron are sometimes used as synonyms because
F₂ generation is produced by
Immunoglobin found in serum is
A late acting dominant disorder is
The inflorescence of Onion is
Vaccines produced through geneticengneering are safe as
Basis of vaccination was discovered by
An Rh⁻ individual receives Rh⁺ blood. The recipient becomes
Which of the following is an ammonifying bacteria ?
Bacteria lack alternation of generation as they
Maximum starch is manufactured by
Bordeaux mixture is a fungicide, which consists of
Companion cells are usually seen associated with
Plastocyanin contain
The specific function of light energy in the process of photosynthesis is to
In Photosystem I, light energy activates electrons of the Photosystem II pigments. These pigments transfer the energy of their excited electrons to a special Photosystem II chlorophyll molecule, P680, that absorbs light best in the red region at 680 nanometers.
A function of enzymes is to
Which of the following hormones does not promote homeostasis?
Which of the following are the most diversed molecules in the cell ?