Bacterial leaf blight of rice is caused by a species

Thermococcus, Methanococcus and Methanobacterium exemplify

In the light of recent classification of living organisms into three domains of life (bacteria, archaea and eukarya), wh

Select one of the following pairs of important features distinguishing Gnetum from Cycas and Pinus and showing affinitie

In which one of the following male and female gametophytes do not have free living independent existance?

Which one of the following is heterosporous?

Which one of the following in birds, indicates their reptilian ancestry?

Which one of the following groups of three animals each is correctly matched with their one characteristic morphological

Ascaris is characterized by

Which one of the following pairs of items correctly belongs to the category of organs mentioned against it?

Which one of the following is not a characteristic of Phylum Annelida?

Which one of the following phyla is correctly matched with its two general characteristics?

Replum is present in the ovary of flower of

The fleshy receptacle of syconus of fig encloses a number of

Endosperm is consumed by developing embryo in the sead of

The fruit is chambered, developed from inferior ovary and has seeds with succulent testa in

Dry indehiscent single-seeded fruit formed from bicarpellary syncarpous inferior ovary is

Carbohydrates are commonly found as starch in plants storage organs. Which of the following five properties of starch (1

Cellulose is the major component of cell walls of

A competitive inhibitor of succinic dehydrogenase is

Modern detergents contain enzyme preparations of

The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap beca

Electrons from excited chlorophyll molecule of photosystem II are accepted first by

In leaves of C4 plants malic acid synthesis during CO2 fixation occurs in

The C4 plants are photosynthetically more efficient than C3 plants because

The energy-releasing metabolic process in which substrate is oxidised without an external electron acceptor is called

The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate (ATP) is formed b

Importance of day length in flowering of plants was first shown in

Senescence as an active developmental cellular process in growth and functioning of a flowering plant, is indicated in

Which one of the following is the correct matching of the site of action on the given substrate, the enzyme acting upon

What will happen if the secretion of parietal cells of gastric glands is blocked with an inhibitor?

In humans, blood passes from the post caval to the diastolic right atrium of heart due to

The most active phagocytic white blood cells are

Which type of white blood cells are connected with the release of histamine and the natural anticoagulant heparin?

Cornea transplant in humans is almost never rejected. This is because

Which one of the following is the correct difference between rod cells and cone cells of our retina?

During the propagation of a nerve impulse, the action potential results from the movement of

Which one of the following pair of organs includes only the endocrine glands?

The blood calcium level is lowered by the deficiency of

Which one of the following is resistant to enzyme action?

What does the filiform apparatus do at the entrance into ovule?

Which one of the following pairs of plant structures has haploid number of chromosomes ?

Unisexuality of flowers prevents

In humans, at the end of the first meiotic division, the male germ cells differentiate into the:

In human adult females oxytocin:

Which one of the following statements is incorrect about menstruation?

Which extraembryonic membrane in humans prevents desiccation of the embryo inside the uterus?

Consider the statements given below regarding contraception and answer as directed thereafter: (i) Medical Termination

Given below are four methods (A-D) and their modes of action (1-4) in achieving contraception. Select their correct matc

Which one of the following conditions in humans is correctly matched with its chromosomal abnormality/linkage?

In the DNA molecule:

Which one of the following pairs of nitrogenous bases of nucleic acids, is wrongly matched with the category mentioned a

Which one of the following pairs of codons is correctly matched with their function or the signal for the particular ami

Polysome is formed by

Darwin's finches are a good example of –

Thorn of Bougainvillea and tendril of Cucurbita are examples of:

Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envis

Which one of the following scientist's name is correctly matched with the theory put fourth by him?

Match the disease in Column I with the appropriate items (pathogen/ prevention/ treatment) in Column II. .tg {border-c

Which one of the following is the correct statement regarding the particular psychotropic drug specified ?

Haploids are more suitable for mutation studies than the diploids. This is because:

Which one of the following is linked to the discovery of Bordeaux mixture as a popular fungicide ?

Consider the following four measures (1-4) that could be taken to successfully grow chickpea in an area where bacterial

Trichoderma harzianum has proved a useful microorganism for:

Nitrogen fixation in root nodules of Alnus is brought about by:

Which one of the following proved effective for biological control of nematodal disese in plants?

Gel electrophoresis is used for:

The linking of antibiotic resistance gene with the plasmid vector became possible with:

Main objective of production/use of herbicide resistant GM crops is to:

Cry I endotoxins obtained from Bacillus thuringiensis are effective against:

Human insulin is being commercially produced from a transgenic species of:

Consider the following four statements (1-4) about certain desert animals such as kangaroo-rat. (i) They have dark colo

Quercus species are the dominant component in:

About 70% of total global carbon is found in:

Consider the following statements concerning food chains: (i) Removal of 80% tigers from an area resulted in greatly in

The slow rate of decomposition of fallen logs in nature is due to their:

The table below gives the populations (in thousands) of ten species (A-J) in four areas (a-d) consisting of the number o

Which one of the following is not observed in biodiversity hotspots ?

World Summit on Sustainable Development (2002) was held in:

A lake near a village suffered heavy mortality of fishes within a few days. Consider the following reasons for this? (i

According to Central Pollution Control Board (CPCB), which particulate size in diameter (in micrometers) of the air poll

Which one of the following is the correct percentage of the two (out of the total of 4) greenhouse gases that contribute

The length of different internodes in a culm of sugarcane is variable because of:

Vascular tissues in flowering plants develop from:

Earthworms have no skeleton but during burrowing the anterior end becomes turgid and acts as a hydraulic skeleton. It is

Which one of the following is the true description about an animal concerned?

Vacuole in a plant cell:

The two sub-units of ribosome remain united at a critical ion level of :

In germinating seeds fatty acids are degraded exclusively in the:

Keeping in view the "fluid mosaic model" for the structure of cell membrane, which one of the following statements is co

Given below is a diagrammatic cross section of a single loop of human cochlea. Which one of the following options corre

A transgenic food crop which may help in solving the problem of night blindness in developing countries is

How many moles of lead (II) chloride will be formed from a reaction between 6.5 g of PbO and 3.2 g HCl ?

An organic compound contains carbon, hydrogen and oxygen. Its elemental analysis gave C, 38.71% and H, 9.67%. The empiri

What volume of oxygen gas (O2) measuread at 0oC and 1 atm, is needed to burn completely 1 L of propane gas (C3H8) measu

The measurement of the electron position is associated with an uncertainty in momentum, which is equal to 1 $$ \times $$

If uncertainty in position and momentum are equal, then uncertainty in velocity is

Which one of the following arrangements does not give the correct picture of the trends indicated against it ?

Four diatomic species are listed below. Identify the correct order in which the bond order is increasing in them

The correct order of increasing bond angles in the following triatomic species is

If a gas expands at constant temperature, it indicates that

Volume occupied by one molecule of water (density = 1 g cm$$-$$3) is

Which of the following are not state functions ? (I) q + w     (II) q (III) w&n

Bond dissociation enthalpy of H2, Cl2 and HCl are 434, 242 and 431 kJ mol$$-$$1 respectively. Enthalpy of formation of H

For the gas phase reaction, PCl5(g)  $$\rightleftharpoons$$ PCl3(g) + Cl2(g) which of the following condition

The dissociation equilibrium of a gass AB2 can be represented as : 2AB2(g) $$\rightleftharpoons$$ 2AB(g) + B2(g) The d

If the concentration of OH$$-$$ ions in the reaction Fe(OH)3(s) $$\rightleftharpoons$$ Fe3+(aq) + 3OH$$-$$(aq) is decr

The value of equilibrium constant of the reaction HI(g) $$\rightleftharpoons$$ $${1 \over 2}$$H2(g) + $${1 \over 2}$$I2

The values of for the reactions, X $$\rightleftharpoons$$ Y + Z      . . . .(i) A $$\r

Equal volumes of three acid solutions of pH 3, 4 and 5 are mixed in a vessel. What will be the H+ ion concentration in t

Base strength of is in the order of

Which one of the following is most reactive towards electrophilic attack?

The stability of carbanions in the following. is in the order of

A (predominantly) is

In the hydrocarbon, The state of hybridization of carbons 1, 3 and 5 are in the following sequence

How many stereoisomers does this molecule have? CH3CH$$=$$CHCH2CHBrCH3

In a SN2 substitution reaction of the type R $$-$$ Br + Cl$$-$$ $$\buildrel {DMF} \over \longrightarrow $$ R$$-$$Cl +

Number of moles of MnO$$_4^{ - }$$ required to oxidize one mole of ferrous oxalate completely in acidic medium will be

Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highe

The alkali metals form salt-like hydrides by the direct synthesis at elevated temperature. The thermal stability of thes

The sequence of ionic mobility in aqueous solution is

A strong base can abstract an $$\alpha $$-hydrogen from

The relative reactivities of acyl compounds towards nucleophilic substitution are in the order of

Acetophenone when reacted with a base, C2H5ONa,   yields a stable compound which has the structure

In a reaction of aniline a coloured product C was obtained. The structure of C would be

In DNA, the complimentary bases are

Which of the following is an amine hormone?

Which one of the following statements is not true?

With which one of the following elements silicon should be doped so as to give p-type of semiconductor?

If $$a$$ stands for the edge length of the cubic systems: simple cubic, body centred cubic and face centred cubic, then

Which of the following statements is not correct?

Percentage of free space in a body centred cubic unit cell is

On the basis of the following Eo values, the strongest oxidizing agent is [Fe(CN)6]4$$-$$ $$ \to $$ [Fe(CN)6]3$$-$$ + e

Kohlrausch's law states that at

Standard free energies of formation (in kJ/mol) at 298 K are $$-$$237.2, $$-$$ 394.4 and $$-$$8.2 for H2O(l), CO2(g) and

The rate constants k1 and k2 for two different reactions are 1016 $$ \cdot $$ e$$-$$2000/T and 1015 $$ \cdot $$ e$$-$$

The bromination of acetone that occurs in acid solution is represented by this equation. CH3COCH3(aq) + Br2(aq) &n

The angular shape of ozone molecule (O3) consists of

The correct order of decreasing second ionisation enthalpy of Ti(22), V(23), Cr(24) and Mn(25) is

Which of the following complexes exhibits the highest paramagnetic behaviour? where gly = glycine, en = ethylenediamin

In which of the following coordination entities the magnitude of $$\Delta $$o (CFSE in octahedral field) will be maximum

Green chemistry means such reactions which

If the error in the measurement of radius of a sphere is 2%, then the error in the determination of volume of the sphere

Which two of the following five physical parameters have the same dimensions ? 1.  Energy density 2. &nb

A particle moves in a straight line with a constant acceleration. It changes its velocity from 10 ms$$-$$1 to 20 ms$$-$$

The distance travelled by a particle starting from rest and moving with an acceleration $${4 \over 3}$$m s$$-$$2, in th

A particle of mass m is projected with velocity v making an angle of 45o with the horizontal. When the particle lands on

A particle shows distance - time curve as given in this figure. The maximum instaneous velocity of the particle is aroun

A roller coaster is designed such that riders experience ''weightlessness'' as they go round the top of a hill whose ra

Sand is being dropped on a conveyer belt at the rate of M kg/s. The force necessary to keep the belt moving with a cons

Three forces acting on a body are shown in the figure. To have the resultant force only along the y-direction, the mag

Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional forces are 1

A shell of mass 200 gm is ejected from a gun of mass 4 kg by an explosion that generates 1.05 kJ of energy. The initial

A thin rod of length L and mass M is bent at its midpoint into two halves so that the angle between them is 90o. The mo

The ratio of the radii of gyration of a circular disc to that of a circular ring, each of same mass and radius, around t

On a new scale of temperature (which is linear) and called the W scale, the freezing and boiling points of water are 39o

At 10oC the value of the density of a fixed mass of an ideal gas divided by it pressure is x. At 110oC this ratio is

If Q, E and W denote respectively the heat added, change in internal energy and the work done in a closed cyclic process

Two simple harmonic motions of angular frequency 100 and 1000 rad s$$-$$1 have the same displacement amplitude. The rati

A point performs simple harmonic oscillation of period T and the equation of motion is given by x = a sin($$\omega $$t +

Two periodic waves of intensities $$I$$1 and $$I$$2 pass through a region at the same time in the same direction. The su

The wave described by y = 0.25 sin(10$$\pi $$x $$-$$ 2$$\pi $$t), where x and y are in metres and t in seconds, is a wav

A parallel plate capacitor has a uniform electric field E in the space between the plates. If the distance between the p

A thin conducting ring of radius R is given a charge +Q. The electric field at the centre O of the ring due to the charg

The electric potential at a point in free space due to charge Q coulomb is Q $$ \times $$ 1011 volts. The electric field

In the circuit shown, the current through the 4 $$\Omega $$ resistor is 1 amp when the points P and M are connected to

A wire of a certain material is stretched slowly by ten percent. Its new resistance and specific resistance become respe

An electric kettle takes 4 A current at 220 V. How much time will it take to boil 1 kg of water from temperature 20oC ?

A current of 3 amp. flows through the 2 $$\Omega $$ resistor shown in the circuit. The power dissipated in the 5 $$\Omeg

A cell can be balanced against 110 cm and 100 cm of potentiometer wire, respectively with and without being short circui

A particle of mass m, charge Q and kinetic energy T enters a transverse uniform magnetic field of induction $$\overright

A closed loop PQRS carrying a current is placed in a uniform magnetic field. If the magnetic forces on segments PS, SR a

A galvanometer of resistance 50 $$\Omega $$ is connected to a battery of 3 V along with a resistance of 2950 $$\Omega $$

Curie temperature above which

A long solenoid has 500 turns. When a current of 2 ampere is passed through it, the resulting magnetic flux linked with

In an a.c. circuit the e.m.f. ($$\varepsilon $$) and the current (i)  at any instant are given respectively b

A circular disc of radius 0.2 meter is placed in a uniform magnetic field of induction $${1 \over \pi }\left( {{{Wb} \ov

The velocity of electromagnetic radiation in a medium of permittivity $$\varepsilon $$0 and permeability $$\mu $$0 is gi

Two thin lenses of focal lengths f1 and f2 are in contact and coaxial. The power of the combination is

A boy is trying to start a fire by focusing sunlight on a piece of paper using an equiconvex lens of focal length 10 cm.

A particle of mass 1 mg has the same wavelength as an electron moving with a velocity of 3 $$ \times $$ 106 m s$$-$$1. T

The work function of a surface of a photosensitive material is 6.2 eV. The wavelength of the incident radiation for whic

In the phenomenon of electric discharge through gases at low pressure, the coloured glow in the tube appears as a result

If M(A; Z), Mp and Mn denote the masses of the nucleus $${}_Z^AX,$$ proton and neutron respectively in units of u (1 u =

Two nuclei have their mass numbers in the ratio of 1 : 3. The ratio of their nuclear densities would be

The ground state energy of hydrogen atom is $$-$$ 13.6 eV. When its electron is in the first excited state, its excitati

Two radioactive materials X1 and X2 have decay constants $$5\lambda $$ and $$\lambda $$ respectively. If initially they

A p-n photodiode is made of a material with a band gap of 2.0 eV. The minimum frequency of the radiation that can be abs

The voltage gain of an amplifier with 9% negative feedback is 10. The voltage gain without feedback will be

If the lattice parameter for a crystalline structure is 3.6 $$\mathop A\limits^ \circ $$, then the atomic radius in fcc