Toxic agents present in food which interfere with thyroxine synthesis lead to the development of

Phototropic curvature is the result of uneven distribution of

What is true about RBCs in humans?

Listed below are four respiratory capacities (i $$-$$ iv) and four jumbled respiratory volumes of a normal human adult.

	Respiratory capacities		Respiratory volumes
(i)	Residual volume		2500 mL
(ii)	Vital capacity		3500 mL
(iii)	Inspiratory reserve volume		1200 mL
(iv)	Inspiratory capacity		4500 mL

Which one of the following is the correct matching of two capacities and volumes?

If due to some injury the chordae tendinae of the tricuspid valve of the human heart is partially non-functional, what will be the immediate effect?

Which two of the following changes (i $$-$$ iv) usually tend to occur in the plain dwellers when they move to high altitudes (3, 500 m or more)?
(i)  Increase in red blood cell size
(ii)  Increase in red blood cell production
(iii)  Increased breathing rate
(iv)  Increase in thrombocyte count
Changes occurring are

Which one of the following is the correct description of a certain part of a normal human skeleton?

Which one of the following statements in regard to the excretion by the human kidneys is correct?

The principal nitrogenous excretory compound in humans is synthesised

The nerve centres which control the body temperature and the urge for eating are contained in

Low Ca⁺⁺ in the body fluid may be the cause of

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

Injury to adrenal cortex is not likely to affect the secretion of which one of the following?

Which one of the following pairs is incorrectly matched?

select the correct matching of a hormone, its source and function.

Transfer of pollen grains from the another to the stigma of another flower of the same plant is called

Wind pollinated flowers are

Apomictic embryos in Citrus arise form

Which one of the following statements about human sperm is correct?

Which one of the following cannot be explained on the basis of Mendel's Law of Dominance?

Vasa efferentia are the ductules leading from :

Select the correct statement from the ones given below with respect to dihybrid cross –

The genotype of a plant showing the dominant phenotype can be determined by –

The part of Fallopian tube closest to the ovary is

Which one of the following statements about all the four of Spongilla, leech, dolphin and penguin is correct?

One of the free-living, anaerobic nitrogen-fixer is

Some hyperthermophilic organisms that grow in highly acidic (pH 2) habitats belong to the two groups

Male and female gametophytes are independent and free-living in

Membrane-bound organelles are absent in

Single-celled eukaryotes are included in

Virus envelope is known as

Algae have cell wall made up of:

Which one of the following statements about certain given animals is correct?

Which one of the following kinds of animals are triploblastic?

One example of animals having a single opening to the outside that serves both as mouth as well as anus is

Seminal plasma in human males is rich in

The scutellum observed in a grain of wheat or maize is comparable to which part of the seed in other monocotyledons?

Keel is characteristic of the flowers of

Ovary is half-inferior in the flowers of

The technical term used for the androecium in a flower of China rose (Hibiscus rosa sinensis) is

C₄ plants are more efficient in photosynthesis than C₃ plants due to

PGA as the first CO₂ fixation product was discovered in photosynthesis of

During mitosis, ER and nucleolus begin to disappear at

Coiling of garden pea tendrils around any support is an example of

Photoperiodism was first characterised in

Which one of the following is an example of ex situ conservation ?

Which of the following are used in gene cloning ?

Some of the characteristics of Bt cotton are –

An improved variety of transgenic basmati rice

Stirred-tank bioreactors have been designed for –

Which one of the following is used as vector for cloning genes into higher organisms ?

Genetic engineering has been successfully used for producing –

DNA or RNA segment tagged with a radioactive moleculer is called –

The genetically-modified (GM) brinjal in India has been developed for:

The figure given below is a diagrammatic representation of response of organisms to abiotic factors. What do a, b and c represent respectively –

Study the four statements (a–d) given below and select the two correct ones out of them –
(a) A lion eating a deer and a sparrow feeding on grain are ecologically similar in being consumers
(b) Predator star fish Pisaster helps in maintaining species diversity of some invertebrates
(c) Predators ultimately lead to the extinction of prey species
(d) Production of chemicals such as nicotine, strychnine by the plants are metaboilic disorders
The two correct stament are-

Which one of the following is one of the characteristics of a biological community?

The biomass available for consumption by the herbivores and the decomposers is called –

Restriction endonucleases are enzymes which –

Which one of the folliwng is not a lateral meristem ?

The chief water conducting elements of xylem in gymnosperms are :

Heartwood differs from sapwood in –

The plasma membrane consists mainly of –

The main area of variuos types of activites of a cell is –

Which one of the following has its own DNA?

Which one of the following structures between two adjacent cells is an effective transport pathway?

Which stages of cell division do the following figures A and B represent respectively?

The cells lining the blood vessels belongs to the category of :

Select the two correct statements out of the four (a-d) statements given below about lac operon.
(a) Glucose or galactose may bind with the repressor and inactivate it
(b) In the absence of lactose the repressor binds with the operator region
(c) The z-gene codes for permease
(d) This was elucidated by Francois Jacob and Jacque Monod
The correct statements are :

The first movements of the foetus and appearance of hair on its head are usually observed during which month of pregnancy?

Sertoli cells are found in :

In vitro fertilization is a technique that involves transfer of which one of the following into the fallopian tube?

Cu ions released from copper-releasing Intra Uterine Devices (IUDs) –

ABO blood groups in humans are controlled by the gene I. It has three alleles – I^A, I^B and i. Since there are three different alleles, six different genotypes are possible. How many phenotypes can occur –

Which one of the following symbols and its representation, used in human pedigree analysis is correct –

Which one of the following statements about morula in humans is correct?

The second maturation division of the mammalian ovum occurs

The permissible use of the technique aminocentesis is for

The one aspect which is not a salient feature of genetic code, is its being –

Which one of the following does not follow the central dogma of molecular biology ?

Which one of the following palindromic base sequences in DNA can be easily cut at about the middle by some particular restriction enzyme?

Darwin's finches are a good example of –

Which one of the following statements is correct with respect to AIDS ?

Widal test is used for the diagnosis of –

A common biocontrol agent for the control of plant diseases is –

Infectious proteins are present in –

Breeding of crops with high levels of minerals, vitamins and proteins is called –

The common nitrogen-fixer in paddy fields is –

Which one of the following not used in organic farming ?

Select the correct statement from the ones given below :

Select the correct statement from the following:

Ringworm in humans is caused by :

Crystal field stabilization energy for high spin d⁴ octahedral complex is

Which one of the following complexes is not expected to exhibit isomerism?

Which of the following complex ions is not expected to absorb visible light?

An increase in equivalent conductance of a strong electrolyte with dilution is mainly due to

Acetamide is treated with the following reagents separately. Which one of these would yield methyl amine?

Among the given compounds, the most susceptible to nucleophilic attack at the carbonyl group is

Aniline in a set of the following reactions yielded a coloured product Y.

The structure of 'Y' would be

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

Which of the following statements about primary amines is false?

A solution of sucrose (molar mass = 342 g mol^$$-$$) has been prepared by dissolving 68.5 g of sucrose in 1000 g of water. The freezing point of the solution obtained will be (K_f for water = 1.86 K kg mol^$$-$$1)

An aqueous solution is 1.00 molal in KI. Which change will cause the vapour pressure of the solution to increase?

For the reaction N₂O_5(g) $$ \to $$  2NO_2(g) + 1/2O_2(g)
the value of rate of disappearance of N₂O₅ is given as 6.25 $$ \times $$ 10^$$-$$3 mol L^$$-$$1 s^$$-$$1. The rate of formation of NO₂ and O₂ is given respectively as

For the reduction of silver ions with copper metal, the standard cell potential was found to be + 0.46 V at 25^oC. The value of standard Gibb's energy, $$\Delta $$G^o will be
(F = 96500 C mol^$$-$$1)

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

The tendency of BF₃, BCl₃ and BBr₃ to behave as Lewis acid decreases in the sequence

Oxidation states of P in H₄P₂O₅, H₄P₂O₆, H₄P₂O₇ are respectively

During the kinetic study of the reaction, 2A + B $$ \to $$ C + D, following results were obtained

Run	[A]/mol L$$-$$1	[B]/mol L$$-$$1	Initial rate of formation of D/mol L$$-$$1 min$$-$$1
I.	0.1	0.1	6.0$$ \times $$10$$-$$3
II.	0.3	0.2	7.2$$ \times $$10$$-$$2
III.	0.3	0.4	2.88$$ \times $$10$$-$$1
IV.	0.4	0.1	2.40$$ \times $$10$$-$$2

Based on the above data which one of the following is correct?

Which one of the following molecular hydrides acts as a Lewis acid?

Which of the following ions will exhibit colour in aqueous solutions?

Which of the following pairs has the same size?

Which of the following ions has electronic configuration [Ar]3d⁶?
(At. nos. Mn = 25, Fe = 26, Co = 27, Ni = 28)

The existance of two different coloured complexes with the composition of [Co(NH₃)₄Cl₂]⁺ is due to

If pH of a saturated solution of Ba(OH)₂ is 12, the value of its K_sp is

The correct order of the decreasing ionic radii among the following isoelectronic species is

25.3 g of sodium carbonate, Na₂CO₃ is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentration of sodium ion, Na⁺ and carbonate ions, CO$${}_3^{2 - }$$ are respectively (Molar mass of Na₂CO₃ = 106 g mol^$$-$$1)

Which of the following represents the correct order of increasing electron gain enthalpy with negative sign for the elements O, S, F and C$$l$$ ?

The number of atoms in 0.1 mol of a triatomic gas is (N_A = 6.02 $$ \times $$ 10²³ mol^$$-$$1)

Which one of the following species does not exist under normal conditions?

In which of the following pairs of molecules/ ions, the central atoms have sp² hybridisation ?

In which one of the following species the central atom has the type of hybridization which is not the same as that present in the other three ?

For an endothermic reaction, energy of activation is E_a and enthalpy of reaction is $$\Delta $$H (both of these in kJ/mol). Minimum value of E_a will be

Standard entropies of X₂, Y₂ and XY₃ are 60, 40 and 50 J K^$$-$$1 mol^$$-$$1 respectively. For the reaction

1/2X₂ + 3/2Y₂ $$\rightleftharpoons$$ XY₃, $$\Delta $$H = $$-$$ 30 kJ,

to be at equilibrium, the temperature should be

In which of the following equilibrium K_c and K_p are not equal?

In a buffer solution containing equal concentration of B^$$-$$ and HB, the K_b for B^$$-$$ is 10^$$-$$10. The pH of buffer solution is

What is [H⁺] in mol/L of a solution that is 0.20 M in CH₃COONa and 0.10 M in CH₃COOH? K_a for CH₃COOH = 1.8 $$ \times $$ 10^$$-$$5

In a set of reactions, ethylbenzene yielded a product D.

D would be

The reaction of toluene with Cl₂ in presence of FeCl₃ gives X and reaction in presence of light gives Y. Thus, X and Y are

In the following the most stable conformation of n-butane is

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

Liquid hydrocarbons can be converted to a mixture of gaseous hydrocarbons by

Given are cyclohexanol (I), acetic acid (II), 2, 4, 6-trinitrophenol (III) and phenol (IV). In these the order of decreasing acidic character will be

Among the following four compounds
(i)  Phenol
(ii)  Methyl phenol
(iii)  Meta-nitrophenol
(iv)  Para-nitrophenol

The acidity order is

Which one is most reactive towards S_N1 reaction?

The correct order of increasing reactivity of

C$$-$$X bond towards nucleophile in the following compounds is

Which of the following compounds has the most acidic nature?

Which of the following reactions will not result in the formation of carbon-carbon bonds?

A beam of cathode rays is subjected to crossed electric (E) and magnetic fields (B). The fields are adjusted such that the beam is not deflected. The specific charge of the cathode rays is given by

(Where V is the potential difference between cathode and anode)

A vibration magnetometer placed in magnetic meridian has a small bar magnet. The magnet executes oscillations with a time period of 2 sec in earth's horizontal magnetic field of 24 microtesla. When a horizontal field of 18 microtesla is produced opposite to the earth's field by placing a current carrying wire, the new time period of magnet will be

Charge q is uniformly spread on a thin ring of radius R. The ring rotates about its axis with a uniform frequency $$f$$ Hz. The magnitude of magnetic induction at the center of the ring is

A galvanometer has a coil of resistance 100 ohm and gives a full scale deflection for 30 mA current. If it is to work as a voltmeter of 30 volt range, the resistance required to be added will be

Consider the following two statements.
(A)  Kirchoff's junction law follows from the conservation of charge.
(B)  Kirchhoff's loop law follows from the conservation of energy.

Which of the following is correct?

A galvanometer has a coil of resistance 100 ohm and gives a full scale deflection for 30 mA current. If it is to work as a voltmeter of 30 volt range, the resistance required to be added will be

A series combination of n₁ capacitors, each of value C₁, is charged by a source of potential difference 4V. When another parallel combination of n₂ capacitors, each of value C₂, is charged by a source of potential difference V, it has the same (total) energy stored in it. as the first combination has. The value of C₂. in terms of C₁, is then

A square current carrying loop is suspended in a uniform magnetic field acting in the plane of the loop. If the force on one arm of the loop is the net force on the remaining three arms of the loop is

A conducting circular loop is placed in a uniform magnetic field, B = 0.025 T with its plane perpendicular to the loop. The radius of the loop is made to shrink at a constant rate of 1 mm s^$$-$$1. The induced emf when the radius is 2 cm, is

Which of the following statement is false for the properties of electromagnetic waves ?

In the given circuit the reading of voltmeter V₁ and V₂ are 300 volts each. The reading of the voltmeter V₃ and ammeter A are respectively

A 220 volt input is supplied to a transformer. The output circuit draws a current of 2.0 ampere at 440 volts. If the efficiency of the transformer is 80%, the current drwn by the primary windings of the transformer is

A lens having focal length f and aperture of diameter d forms an image of intensity I. Aperture of diameter $${d \over 2}$$ in central region of lens is covered by a black paper. Focal length of lens and intensity of image now will be respectively

A square surface of side L meter in the plane of the paper is placed in a uniform electric field $$E$$(volt/m) acting along the same plane at an angle $$\theta $$ with the horizontal side of the square as shown in figurre.


The electric flux linked to the surface, in units of volt m is

A ray of light travelling in a transparent medium of refractive index $$\mu $$, falls on a surface separating the medium from air at an angle of incidence of 45^o. For which of the following value of $$\mu $$ the ray can undergo total internal reflection ?

The potential difference that must be applied to stop the fastest photoelectrons emitted by a nickel surface, having work functions 5.01 eV, when ultraviolet light of 200 nm falls on it, must be

A source S₁ is producing, 10¹⁵ photons per second of wavelength 5000 $$\mathop A\limits^ \circ $$. Another source S₂ is producing 1.02 $$ \times $$ 10¹⁵ photons per second of wavelength 5100 $$\mathop A\limits^ \circ $$. Then, (power of S₂)/(power of S₁) is equal to

An alpha nucleus of energy $${1 \over 2}$$ mv² bombards a heavy nuclear target of charge Ze. Then the distance of closest approach for the alpha nucleus will be proportional to

The mass of a $${}_3^7Li$$ Li nucleus is 0.042 u less than the sum of the masses of all its nucleons. The binding energy per nucleon of $${}_3^7Li$$ nucleus is nearly

The energy of a hydrogen atom in the ground state is $$-$$ 13.6 eV. The energy of a He⁺ ion in the first excited state will be

The energy of a hydrogen atom in the ground state is $$-$$ 13.6 eV. The energy of a He⁺ ion in the first excited state will be

The device that can act as a complete electronic circuit is

Which one of the following statement is false ?

To get an output Y = 1 in given circuit which of the following input will be correct ?

Which one of the following bonds produces a solid that reflects light in the visible region and whose electrical conductivity decreases with temperature and has high melting point ?

Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature t^oC, the power received by a unit surface, (normal to the incident rays) at a distance R from the centre of the sun is
where $$\sigma $$ is the Stefan's constant.

The dimension of $${1 \over 2}{\varepsilon _0}{E^2}$$, where $${\varepsilon _0}$$ is permittivity of free space and E is electric field, is

A ball is dropped from a high rise platform at t = 0 starting from rest. After 6 seconds another ball is thrown downwards from the same platform with a speed v. The two balls meet at t = 18 s. What is the value of v?
(Take g = 10 m/s²)

Six vectors, $$\overrightarrow a $$ through $$\overrightarrow f $$ have the magnitudes and directions indicated in the figure. Which of the following statements is true ?

A block of mass m is in contact with the cart C as shown in the figure.

The coefficient of static friction between the block and the cart is $$\mu $$. The acceleration $$\alpha $$ of the cart that will prevent the block from falling satisfies

A particle has initial velocity $$\left( {3\widehat i + 4\widehat j} \right)$$ and has acceleration $$\left( {0.4\widehat j + 0.3\widehat j} \right).$$ Its speed after 10 s is

A ball moving with velocity 2 m/s collides head on with another stationary ball of double the mass. If the coefficient of restitution is 0.5, then their velocities (in m/s) after collision will be

An engine pumps water through a hose pipe. Water passes through the pipe and leaves it with a velocity of 2 m/s. The mass per unit length of water in the pipe is 100 kg/m. What is the power of the engine?

A circular disk of moment of inertia $${I_t}$$ is rotating in a horizontal plane, about its symmetry axis, with a constant angular speed $${\omega _i}$$. Another disk of moment of inertia $${I_b}$$ is dropped coaxially onto the rotating disk. Initially the second disk has zero angular speed. Eventually both the disks rotate with a constant angular speed $$\omega $$. The energy lost by the initially rotating disc to friction is

Two particles which are initially at rest, move towards each other under the action of their internal attraction. If their speeds are v and 2v at any instant, then the speed of centre of mass of the system will be :

A gramophone record is revolving with an angular velocity $$\omega $$. A coin is placed at a distance r from the centre of the record. The static coefficient of friction is $$\mu $$. The coin will revolve with the record if

A man of 50 kg mass is standing in a gravity free space at a height of 10 m above the floor. He throws a stone of 0.5 kg mass downwards with a speed 2 m/s. When the stone reaches the floor, the distance of the man above the floor will be

The total radiant energy per unit area, normal to the direction of incidence, received at a distance R from the centre of a star of radius r, whose outer surface radiates as a black body at a temperature TK is given by

A cylindrical metallic rod in thermal contact with two reservoirs of heat at its two ends conducts an amount of heat Q in time t. The metallic rod is melted and the material is formed into a rod of half the radius of the original rod. What is the amount of heat conducted by the new rod, when placed in thermal contact with the two reservoirs in time t?

A particle of mass M is situated at the centre of a spherical shell of same mass and radius a. The magnitude of the gravitational potential at a point sutuated at a/2 distance from the centre, will be :

The radii of circular orbits of two satellites A and B of the earth, are 4R and R, respectively. If the speed of satellite A is 3V, then the speed of satellite B will be

The displacement of a particle along the x-axis is given by x = asin²$$\omega $$t. The motion of the particle corresponds to

A transverse wave is represented by
y = Asin($$\omega $$t $$-$$ kx). For what value of the wavelength is the wave velocity equal to the maximum particle velocity ?

If $$\Delta $$U and $$\Delta $$W represent the increase in internal energy and work done by the system respectively in a thermodynamical process, which of the following is true ?

A tuning fork of frequency 512 Hz makes 4 beats per second with the vibrating string of a piano. The beat frequency decreases to 2 beats per sec when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was

The period of oscillation of a mass M suspended from a strong of negligible mass is T. If along with it another mass M is also suspended, the period of oscillation will now be

A potentiometer circuit is set up as shown. The potential gradient, across the potentiometer wire, is k volt/cm and the ammeter, present in the circuit, reads 1.0 A when two way key is switched off. The balance points, when the key between the terminals (i) 1 and 2 (ii) 1 and 3, is plugged in, are found to be at length $$l$$₁ cm and $$l$$₂ cm respectively. The magnitudes, of the resistors R and X, in ohms, are then, equal, respectively, to

Electromagnets are made of soft iron because soft iron has

Two positives ions, each carrying a charge q, are separated by a distance d. If F is the force of repulsion between the ions, the number of electrons missing from each ion will be (e being the charge on an electron)

A particle moves a distance x in time t according to equation x = (t + 5)^$$-$$1. The acceleration of particle is proportional to