In which of the following processes, heat is neither absorbed nor released by a system?
Increase in temperature of a gas filled in a container would lead to :
Increase in temperature would lead to the
increase in kinetic energy of gas (assuming
far as to be ideal) as
The total energy of an electron in an atom in an orbit is –3.4 eV. Its kinetic and potential energies are, respectively:
In Bohr's model of H atom
∴ K.E. = 3.4 eV
U = –6.8 eV
The correct Boolean operation represented by the circuit diagram drawn is :
From the given logic circuit LED will glow,
when voltage across LED is high.
Truth Table
This is output of NAND gate.
A block of mass 10 kg is in contact against the inner wall of a hollow cylindrical drum of radius 1 m. The coefficient of friction between the block and the inner wall of the cylinder is 0.1. The minimum angular velocity needed for the cylinder to keep the block stationary when the cylinder is vertical and rotating about its axis, will be : (g 10 m/s2 )
For equilibrium of the block limiting friction
fL≥ mg
⇒ μN ≥ mg
Body A of mass 4m moving with speed u collides with another body B of mass 2m, at rest. The collision is head on and elastic in
nature. After the collision the fraction of energy lost by the colliding body A is :
Fractional loss of KE of colliding body
The speed of a swimmer in still water is 20 m/s. The speed of river water is 10 m/s andis flowing due east. If he is standing on the south bank and wishes to cross the river along the shortest path, the angle at which he should make his strokes w.r.t. north is given by :
VSR = 20m/s
VRG = 10m/s
sin θ = 10/20
sin θ = 1/2
θ = 300 west
A mass m is attached to a thin wire and whirled in a vertical circle. The wire is most likely to break when:
The tension is maximum at the lowest position of mass, so the chance of breaking is maximum.
The displacement of a particle executing simple harmonic motion is given by
y = A0+ Asinωt + Bcosωt
Then the amplitude of its oscillation is given by :
y = A0+ Asinωt + Bsinωt
Equate SHM
y' = y – A0 = Asinωt + Bcosωt
Resultant amplitude
A 800 turn coil of effective area 0.05 m2 is kept perpendicular to a magnetic field 5 × 10–5 T. When the plane of the coil is rotated by 90° around any of its coplanar axis in 0.1 s, the emf induced in the coil will be:
Magnetic field B = 5 × 10–5 T
Number of turns in coil N = 800
Area of coil A = 0.05 m2
Time taken to rotate Δt = 0.1 s
Initial angle θ1 = 0°
Final angle θ2= 90°
Change in magnetic flux Δφ
= NBAcos90° –NBAcos0°
= – NBA
= – 800 × 5 × 10–5 × 0.05
= – 2 × 10–3 weber
Average velocity of a particle executing SHM in one complete vibration is :
In one complete vibration, displacement is zero. So, average velocity in one complete vibration
A soap bubble, having radius of 1 mm, is blown from a detergent solution having a surface tension of 2.5 × 10-2 N/m. The pressure inside the bubble equals at a point Z0 below the free surface of water in a container. Taking g = 10 m/s2, density of water = 103 kg/m3, the value of Z0 is
Excess pressure = 4T/R, Gauge pressure
A copper rod of 88 cm and an aluminium rod of unknown length have their increase in length independent of increase in temperature. The length of aluminium rod is:
(αCu = 1.7 × 10-5 K-1 and αAl = 2.2 × 10-5 K-1)
αCuLCu = αAlLAl
1.7 × 10–5 × 88 cm = 2.2 × 10-5 × LAl
The unit of thermal conductivity is :
The heat current related to difference of temperature across the length l of a conductor of area A is
(K = coefficient of thermal conductivity)
Unit of K = Wm–1 K–1
When a block of mass M is suspended by a long wire of length L, the length of the wire becomes (L + l). The elastic potential energy stored in the extended wire is :
U = 1/2 ((work done by gravity)
A disc of radius 2 m and mass 100 kg rolls on a horizontal floor. Its centre of mass has speed of 20 cm/s. How much work is needed to stop it?
Work required = change in kinetic energy Final KE = 0
Initial KE
|ΔKE| = 3 J
In an experiment, the percentage of error occurred in the measurement of physical quantities A, B, C and D are 1%, 2%, 3% and 4% respectively. Then the maximum percentage of error in the measurement X, where will be
Given
= 2% + 1%+ 1%+ 12%
= 16%
A body weighs 200 N on the surface of the earth. How much will it weigh half way down to the centre of the earth ?
Acceleration due to gravity at a depth d from surface of earth
Where g = acceleration due to gravity at earth's surface
Multiplying by mass 'm' on both sides of (1)
Which colour of the light has the longest wavelength?
Red has the longest wavelength among the given options.
A solid cylinder of mass 2 kg and radius 4 cm is rotating about its axis at the rate of 3 rpm. The torque required to stop after 2π revolutions is
Work energy theorem.
θ = 2π revolution
= 2π × 2π = 4π2 rad
The radius of circle, the period of revolution, initial position and sense of revolution are indicated in the fig.
y - projection of the radius vector of rotating particle P is :
At t = 0, y displacement is maximum, so equation will be cosine function.
T = 4 s
y = a cosωt
A hollow metal sphere of radius R is uniformly charged. The electric field due to the sphere at a distance r from the centre
Charge Q will be distributed over the surface of hollow metal sphere. (i) For r < R (inside)
By Gauss law,
⇒ Ein = 0 (∵ qen = 0)
(ii) For r > R (outside)
In which of the following devices, the eddy current effect is not used?
Electric heater does not involve Eddy currents. It uses Joule's heating effect.
Six similar bulbs are connected as shown in the figure with a DC source of emf E and zero internal resistance.
The ratio of power consumption by the bulbs when (i) all are glowing and (ii) in the situation when two from section A and one from section B are glowing, will be :
(i) All bulbs are glowing
(ii) Two from section A and one from section B are glowing.
At a point A on the earth's surface the angle of dip σ = + 25°. At a point B on the earth's surface the angle of dip, σ = - 25°. We can interpret that :
point A is located in the Northern hemisphere and point B is located in the southern hemisphere.
basically, angle of dip is the angle made by resultant earth's magnetic field from horizontal.
here, at point A on the earth's surface,
angle of dip is +25° (i.e., positive) so, point A is located in the Northern hemisphere
and point B on the earth's surface, angle of dip is -25° (i.e., negative) so, point B is located in he southern hemisphere.
A force F = 20 + 10 y acts on a particle in y direction where F is in newton and y in meter. Work done by this force to move the particle from y = 0 to y = 1 m is
Work done by variable force is
Pick the wrong answer in the context with rainbow.
Rainbow can't be observed when observer faces towards sun.
A cylindrical conductor of radius R is carrying a constant current. The plot of the magnitude of the magnetic field. B with the distance d from the centre of the conductor, is correctly represented by the figure :
Inside (d < R) Magnetic field inside conductor
or B = Kd ...(i)
Straight line passing through origin
At surface (d = R)
...(ii)
Maximum at surface
Outside (d > R)
Two particles A and B are moving in uniform circular motion in concentric circles of radii rA and rB with speed vA and vB respectively. Their time period of rotation is the same. The ratio of angular speed of A to that of B will be :
Two similar thin equi-convex lenses, of focal length f each, are kept coaxially in contact with each other such that the focal length of the combination is F1. When the space between the two lenses is filled with glycerine (which has the same refractive index (μ = 1.5) as that of glass) then the equivalent focal length is F2. The ratio F1 : F2 will be :
Equivalent focal length in air
When glycerin is filled inside, glycerin lens behaves like a diverging lens of focal length (–f)
In total internal reflection when the angle of incidence is equal to the critical angle for the pair of media in contact, what will be angle of refraction?
At i = ic, refracted ray grazes with the surface.
So angle of refraction is 90°.
Two parallel infinite line charges with linear charge densities +λ C/m and λl C/m are placed at a distance of 2R in free space. What is the electric field mid-way between the two line charges?
Electric field due to line charge (1)
Electric field due to line charge (2)
For a p-type semiconductor, which of the following statements is true ?
In p-type semiconductor, an intrinsic semiconductor is doped with trivalent impurities, that creates deficiencies of valence electrons called holes which are majority charge carriers.
Which of the following acts as a circuit protection device?
Fuse wire has less melting point so when excess current flows, due to heat produced in it, it melts.
A parallel plate capacitor of capacitance 20 mF is being charged by a voltage source whose potential is changing at the rate of 3 V/s. The conduction current through the connecting wires, and the displacement current through the plates of the capacitor, would be, respectively.
Capacitance of capacitor C = 20 mF
= 20 × 10-6 F
Rate of change of potential
ic = 20 × 10–6 × 3
= 60 × 10–6 A
= 60 μA
As we know that id = ic = 60 mA
In the circuits shown below, the readings of the voltmeters and the ammeters will be
For ideal voltmeter, resistance is infinite and for the ideal ammeter, resistance is zero.
α-particle consists of :
α-particle is nucleus of Helium which has two protons and two neutrons.
An electron is accelerated through a potential difference of 10,000 V. Its de Broglie wavelength is, (nearly) : (me = 9 × 10–31 kg)
For an electron accelerated through a potential V
When an object is shot from the bottom of a long smooth inclined plane kept at an angle 60° with horizontal, it can travel a distance x1 along the plane. But when the inclination is decreased to 30° and the same object is shot with the same velocity, it can travel x2 distance.
Then x1 : x2 will be:
A small hole with area of cross-section 2 mm2 is present near the bottom of a fully filled open tank of height 2 m. Taking g = 10 m/s2, the rate of flow of water through the open hole would be nearly
Rate of liquid flow
Two point charges A and B, having charges +Q and –Q respectively, are placed at certain distance apart and force acting between them is F. If 25% charge of A is transferred to B, then force between the charges becomes :
If 25% of charge of A transferred to B then
Ionized hydrogen atoms and α-particles with same momenta enters perpendicular to a constant magnetic field, B. The ratio of their radii of their paths rH : ra will be :
A particle moving with velocity is acted by three forces shown by the vector triangle PQR.
The velocity of the particle will :
As forces are forming closed loop in same order
The work done to raise a mass m from the surface of the earth to a height h, which is equal to the radius of the earth, is:
Initial potential energy at earths surface is
Final potential energy at height h = R
As work done = Change in PE
∴ W = Uf – Ui
(∵ GM = gR2)
In a double slit experiment, when light of wavelength 400 nm was used, the angular width of the first minima formed on a screen placed 1 m away, was found to be 0.2°. What will be the angular width of the first minima, if the entire experimental apparatus is immersed in water? (μwater = 4/3)
In air angular fringe width
Angular fringe width in water
Under isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is
(Given that 1 L bar = 100 J)
∴ Wirr = – Pext ΔV
= – 2 bar × (0.25 – 0.1) L
= – 2 × 0.15 L-bar
= – 0.30 L-bar
= – 0.30 × 100 J
= – 30 J
A compound is formed by cation C and anion A. The anions form hexagonal close packed (hcp) lattice and the cations occupy 75% of octahedral voids. The formula of the compound is :
Anions(A) are in hcp, so number of anions (A) = 6
Cations(C) are in 75% O.V., so number of cations (C)
= 18/4
= 9/2
So formula of compound will be
C9A12 ⇒ C3A4
pH of a saturated solution of Ca(OH)2 is 9. The solubility product (Ksp) of Ca(OH)2 is:
pH = 9 Hence pOH = 14 – 9 = 5
[OH–] = 10–5 M
Thus Ksp = [Ca2+][OH–]2
The number of moles of hydrogen molecules required to produce 20 moles of ammonia through Haber's process is :
Haber's process
20 moles need to be produced
2 moles of NH3 → 3 moles of H2
Hence 20 moles of moles of H2
For an ideal solution, the correct option is :
For ideal solution,
Δmix H = 0
Δmix S > 0
Δmix G < 0
Δmix V = 0
For a cell involving one electron E°cell = 0.59 V at 298 K, the equilibrium constant for the cell reaction is :
(At equilibrium, Q = Keq and Ecell = 0)
(from equation (i))
Among the following, the one that is not a green house gas is
Fact
SO2 (g) is not a greenhouse gas.
The number of sigma (s) and pi (p) bonds in pent-2-en-4-yne is
Number of σ bonds = 10
and number of π bonds = 3
Which of the following diatomic molecular species has only π bonds according to Molecular Orbital Theory?
MO configuration C2 is:
Which of the following reactions are disproportionation reaction?
(a) 2Cu+ → Cu2++ Cu0
(b)
(c)
(d)
Select the correct option from the following
Disproportionation
Disproportionation
∴ Not a disproportionation
Among the following, the narrow spectrum antibiotic is :
Penicillin G is a narrow spectrum antibiotic. It is used for the specific infection when the causative organism is known and will not kill as many of the normal microorganisms as a broad spectrum antibiotic in the body.
The correct order of the basic strength of methyl substituted amines in aqueous solution is :
In aqueous solution, electron donating inductive effect, solvation effect (H-bonding) and steric hindrance all together affect basic strength of substituted amines
Basic character :
Which mixture of the solutions will lead to the formation of negatively charged colloidal [Agl]l– sol ?
Generally charge present on the colloid is due to adsorption of common ion from dispersion medium. Millimole of KI is maximum in option (2) (50 × 2 = 100) so act as solvent and anion I– is adsorbed by the colloid AgI formed
Conjugate base for acids H2O and HF are :
HF on loss of ion becomes
is the conjugate base of HF
Example :
Which will make basic buffer?
This is basic solution due to NaOH.
This is not basic buffer.
Hydrolysis of salt takes place.
This is not basic buffer.
This is basic buffer
⇒ Neutral solution
The compound that is most difficult to protonate is :
Due to involvement of lone pair of electrons in resonance in phenol, it will have positive charge (partial), hence incoming proton will not be able to attack easily.
The most suitable reagent for the following conversion, is :
Which of the following species is NOT stable?
Due to presence of d-orbital in Si, Ge and Sn they form species like SiF62–, [GeCl6]2–, [Sn(OH)6]2–
SiCl62– does not exist because six large chloride ions cannot be accommodated around Si4+ due to limitation of its size.
Which of the following is an amphoteric hydroxide?
Be(OH)2 amphoteric in nature, since it can react both with acid and base
Be(OH)2 + 2HCl → BeCl2 + 2H2O Be(OH)2 + 2NaOH → Na2 [Be(OH)4]
The structure of intermediate A in the following reaction, is
The manganate and permanganate ions are tetrahedral, due to :
Manganate (MnO42–) :
⇒ π-bonds are of dπ-pπ type
Permanganate (MnO4–) :
⇒ π-bonds are of dπ-pπ type
For the second period elements the correct increasing order of first ionisation enthalpy is:
‘Be’ and ‘N’ have comparatively more stable valence sub-shell than ‘B’ and ‘O’.
∴ Correct order of first ionisation enthalpy is:
Li < B < Be < C < O < N < F < Ne
If the rate constant for a first order reaction is k, the time (t) required for the completion of 99% of the reaction is given by:
First order rate constant is given as,
99% completed reaction,
Identify the incorrect statement related to PCl5 from the following:
(1) True
(3) True
Axial bond : 240 pm
Equatorial bond : 202 pm
(4) False
Due to longer and hence weaker axial bonds, PCl5 is a reactive molecule.
4d, 5p, 5f and 6p orbitals are arranged in the order of decreasing energy. The correct option is
(n + l) values for, 4d = 4 + 2 = 6
5p = 5 + 1 = 6
5f = 5 + 3 = 8
6p = 6 + 1 = 7
∴ Correct order of energy would be
5f > 6p > 5p > 4d
The biodegradable polymer is:
Nylon 2–nylon-6 is a polyamide copolymerization of glycine (H2N−CH2−COOH) and aminocaproic acid (H2N−(CH2)5−COOH). It is an example of a biodegradable polymer. Used as a thread in bristles for toothbrushes and making strings of musical instruments.
Match the Xenon compounds in Column-I with its structure in Column-II and assign the correct code:
Which is the correct thermal stability order for H2E (E = O, S, Se, Te and Po)?
On going down the group thermal stability order for H2E decreases because H–E bond energy decreases
∴ Order of stability would be:-
H2Po < H2Te < H2Se < H2S < H2O
The correct structure of tribromooctaoxide is
The correct structure is
An alkene "A" on reaction with O3 and Zn–H2O gives propanone and ethanal in equimolar ratio. Addition of HCl to alkene "A" gives "B" as the major product. The structure of product "B" is:
Enzymes that utilize ATP in phosphate transfer require an alkaline earth metal (M) as the cofactor. M is :
All enzymes that utilize ATP in phosphate transfer require magnesium(Mg) as the co-factor.
Which one is malachite from the following?
Malachite : CuCO3.Cu(OH)2 (Green colour)
Which of the following series of transitions in the spectrum of hydrogen atom fall in visible region?
In H-spectrum, Balmer series transitions fall in visible region.
The mixture that forms maximum boiling azeotrope is:
Solutions showing negative deviation from Raoult's law form maximum boiling azeotrope
Water and Nitric acid → forms maximum boiling azeotrope
For the cell reaction
at 298 K. The standard Gibbs
energy of the cell reaction is :
[Given that Faraday constant F = 96500 C mol–1]
= – 2 × 96500 × 0.24 J mol–1
= – 46320 J mol–1
= – 46.32 kJ mol–1
In which case change in entropy is NEGATIVE?
Expansion of gas at constant temperature, ΔS > 0
Sublimation of solid to gas, ΔS > 0
2H(g) → H2(g), ΔS < 0 (∵ Δng < 0)
Match the following :
Which of the following is the CORRECT option?
Which of the following is INCORRECT statement?
(i) PbF4 is not covalent in nature. Because Pb atom is very & F atom is very small, so according to Fajan's rule, PbF4 is not covalent.
(ii) SiCl4 is not a very stable compound because of steric hindrance thus can be hydrolysed very easily
(iii) GeX4 is more stable than GeX2 as in GeX4 all the orbitals are fully filled.
(iv) SnF4 is ionic in nature. Because F atom is very small & Sn atom is very large, so according to Fajan's rule, it is ionic in nature.
The non-essential amino acid among the following is:
Nonessential means that our bodies produce an amino acid, even if we do not get it from the food we eat. Nonessential amino acids include: alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine.
A gas at 350 K and 15 bar has molar volume 20 percent smaller than that for an ideal gas under the same conditions. The correct option about the gas and its compressibility factor (Z) is :
Compressibility factor(Z)
∵ Vreal < Videal; Hence Z < 1
If Z < 1, attractive forces are dominant among gaseous molecules and liquefaction of gas will be easy.
Among the following, the reaction that proceeds through an electrophilic substitution, is:
Generation of electrophile:
The major product of the following reaction is:
For the chemical reaction
The correct option is:
Rate of reaction is given as
What is the correct electronic configuration of the central atom in K4[Fe(CN)6] based on crystal field theory?
K4[Fe(CN)6]
Fe ground state: [Ar]3d64s2
Fe2+: 3d64s0
The method used to remove temporary hardness of water is :
Clark's method is used to remove temporary hardness of water, in which bicarbonates of calcium and magnesium are reacted with slaked lime Ca(OH)2
Which of the following statements is INCORRECT?
Infective constituent in viruses is either DNA or RNA, not protein.
Purines found both in DNA and RNA are
Purines found both in DNA and RNA are Adenine and guanine
Which of the following glucose transporters is insulin-dependent?
GLUT-IV is insulin dependent and is responsible for majority of glucose transport into muscle and adipose cells in anabolic conditions. Whereas GLUT-I is insulin independent and is widely distributed in different tissues.
Identify the cells whose secretion protects the lining of gastro-intestinal tract from various enzymes.
Goblet cells secrete mucus and bicarbonates present in the gastric juice which plays an important role in lubrication and protection of the mucosal epithelium from excoriation by the highly concentrated HCl.
Which one of the following equipments is essentially required for growing microbes on a large scale, for industrial production of enzymes?
To produce enzyme in lar g e quantity equipment required are bioreactors. Large scale production involves use of bioreactors.
Which of the following is true for Golden rice?
Golden rice is vitamin A enriched rice, with a gene from daffodil and is rich in carotene.
Which one of the following is not a method of in situ conservation of biodiversity?
Botanical garden - ex - situ conservation (offsite conservation) i.e. living plants (flora) are conserved in human managed system.
Under which of the following conditions will there be no change in the reading frame of following mRNA? 5´AACAGCGGUGCUAUU3´
No change in reading frame of m-RNA.
Which of these following methods is the most suitable for disposal of nuclear waste?
Storage of nuclear waste should be done in suitably shielded containers and buried within rocks deep below the earth's surface (500 m deep)
Match the following organisms with the products they produce
Select the correct option.
Microbes are used in production of several household and industrial products –
Lactobacillus – Production of curd
Saccharomyces cerevisiae – Bread making
Aspergillus niger – Citric acid production
Acetobacter aceti – Acetic acid
What map unit (Centimorgan) is adopted in the construction of genetic maps?
1 map unit represent 1 % cross over.
Map unit is used to measure genetic distance.
This genetic distance is based on average number of cross over frequency.
Select the hormone-releasing Intra-Uterine Devices.
Progestasert and LNG-20 are hormone releasing IUDs which make the uterus unsuitable for implantation and the cervix hostile to sperms.
Which of the following can be used as a biocontrol agent in the treatment of plant disease?
Fungus Trichoderma is a biological control agent being developed for use in the treatment of plant diseases.
Expressed Sequence Tags (ESTs) refers to :
Expressed Sequence Tags (ESTs) are DNA sequences (genes) that are expressed as mRNA for protein synthesis. These are used in human Genome Project.
Colostrum the yellowish fluid, secreted by mother during the initial days of lactation is very essential to impart immunity to the new born infants because it contains
Colostrum, the yellowish fluid secreted by the mother during initial days of lactation is very essential to impart immunity to the new born infant because it contains Immunoglobulin A.
It will impart naturally acquired passive immunity to the newborn
Select the INCORRECT statement.
Inbreeding exposes harmful recessive genes that are eliminated by selection. It also helps in accumulation of superior genes and elimination of less desirable genes. Therefore this is selection at each step, increase the productivity of inbred population. Close and continued inbreeding usually reduces fertility and even productivity.
Select the correct sequence for transport of sperm cells in male reproductive system.
The correct sequence for transport of sperm cells in male reproductive system is Seminiferous tubules → Rete testis → Vasa efferentia → Epididymis → Vas deferens → Ejaculatory duct → Urethra → Urethral meatus
A gene locus has two alleles A, a. If the frequency of dominant allele A is 0.4, then what will be the frequency of homozygous dominant, heterozygous and homozygous recessive individuals in the population?
Frequency of dominant allele (say p) = 0.4
Frequency of recessive allele (say q)
= 1 – 0.4 = 0.6
∴ Frequency of homozygous dominant individuals (AA)
= p2 = (0.4)2 = 0.16
Frequency of heterozygous individuals (Aa)
= 2pq = 2(0.4)(0.6) = 0.48
Frequency of homozygous recessive individuals (aa)
= q2 = (0.6)2 = 0.36
Match the following organisms with their respective characteristics :
Select the correct option from the following :
(a) Pila is a Mollusc. The mouth contains a file - like rasping organ for feeding called radula.
(b) Bombyx is an Arthropod. In Bombyx excretion takes place through malpighan tubules.
(c) Pleurobrachia is Ctenophore. The body bears eight external rows of ciliated comb plates, which help in locomotion.
(d) Taenia is a platyhelminth specialised cells called flame cells helps in osmoregulation and excretion
The shorter and longer arms of a submetacentric chromosome are referred to as
Sub metacentric chromosome is Heterobrachial.
Short arm designated as 'p' arm (p = petite i.e. short)
Long arm designated as 'q' arm
What is the site of perception of photoperiod necessary for induction of flowering in plants?
During flowering, photoperiodic stimulus is perceived by leaves of plants.
Which part of the brain is responsible for thermoregulation?
Hypothalamus in the thermoregulatory centre of our brain. It is responsible for maintaining constant body temperature.
Which of the following pair of organelles does not contain DNA?
Lysosomes and Vacuoles do not have DNA.
What is the genetic disorder in which an individual has an overall masculine development gynaecomastia, and is sterile ?
Individuals with Klinefelter’s syndrome have trisomy of sex chromosome as 44 + XXY (47).
They show overall masculine development, gynaecomastia and are sterile.
Xylem translocates.
Xylem is associated with tanslocation of mainly water, mineral salts, some organic nitrogen and hormones.
Which of the following pairs of gases is mainly responsible for green house effect?
Relative contribution of various greenhouse gases to total global warming is
-CO2 = 60%
-CH4 = 20%
-CFC = 14%
-N2O = 6%
⇒Therefore CO2 and CH4 are the major greenhouse gases
Which of the following protocols did aim for reducing emission of chlorofluorocarbons into the atmosphere?
To control the deleterious ef fect of the stratospheric ozone depletion an international treaty was signed at Montreal, Canada in 1987. It is popularly known as Montreal protocol.
In some plants, the female gamete develops into embryo without fertilization. This phenomenon is known as
The phenomenon in which female gamete develops into embryo without getting fused with male gamete (fertilisation) is called parthenogenesis.
Which of the following sexually transmitted diseases is not completely curable?
Genital herpes is caused by type-II-herpes simplex virus. At present there is no cure for type-II-herpes simplex virus and therefore the disease caused, genital herpes. Other noncurable STIs are hepatitis-B and HIV.
Which of the following immune responses is responsible for rejection of kidney graft?
The body is able to differentiate self and nonself and the cell-mediated response is responsible for graft rejection.
Which of the following factors is responsible for the formation of concentrated urine?
The proximity between loop of henle and vasa recta as well as counter current in them help in maintaining an increasing osmolalrity towards the inner medullary interstitium. This mechanism help to maintain a concentration gradient in medullary interstitium so human urine is nearly four times concentrated than initial filtrate formed.
Which of the following features of genetic code does allow bacteria to produce human insulin by recombinant DNA technology?
In recombinant DNA technology bacteria is able to produce human insulin because genetic code is nearly universal.
Which of the following statements is NOT correct?
Lysosomes bud off from trans face of Golgi bodies.
Precursor of lysosomal enzymes are synthesised by RER and then send to Golgi bodies for further processing.
The concept of “ Omnis cellula-e cellula ” regarding cell division was first proposed by
Concept of “Omnis cellula-e cellula” regarding cell division was proposed by Rudolph Virchow.
Use of an artificial kidney during hemodialysis may result in :
(a) Nitrogenous waste build-up in the body
(b) Non-elimination of excess potassium ions
(c) Reduced absorption of calcium ions from gastro-intestinal tract
(d) Reduced RBC production
Which of the following options is the most appropriate?
a and b statements are incorrect because dialysis eliminates urea and potassium from the body whereas, c and d are correct. As phosphate ions are eliminated during dialysis, along with that calcium ions are also eliminated. So, there will be reduced absorption of calcium ions from gastrointestinal tract. RBC production will be reduced, due to reduced erythropoietin hormone.
What is the direction of movement of sugars in phloem?
The direction of movement of sugar in phloem is bi-directional as it depends on source-sink relationship which is variable in plants.
Which of the following muscular disorders is inherited?
Progressive degeneration of skeletal muscle mostly due to genetic disorder is muscular dystrophy where as tetany is muscular spasm due to low calcium in body fluid. Myasthenia gravis is an anto immume disorder leading to paralysis of skeletal muscles. Botulism is rare and dangerous type of food poisoning caused by bacterium Clostridium Botulinum.
Consider following features
(a) Organ system level of organisation
(b) Bilateral symmetry
(c) True coelomates with segmentation of body
Select the CORRECT option of animal groups which possess all the above characteristics
True segmentation is present in Annelida, Arthropoda and Chordata. They also have organ system level of organisation, bilateral symmetry and are true coelomates
The frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes was explained by :
Alfred Sturtevant explained chromosomal mapping on the basis of recombination frequency which is directly proportional to distance between two genes on same chromosome
Following statements describe the characteristics of the enzyme Restriction Endonuclease. Identify the INCORRECT statement.
Restriction enzymes cut DNA molecules at a particular point by recognising a specific sequence. Each restriction endonuclease functions by inspecting the length of a DNA sequence. Once it finds its specific recognition sequence, it will bind to the DNA and cut each of the two strands of the double helix at specific points in their sugarphosphate backbone.
Which of the following statements is INCORRECT?
Yeast is an unicellular sac fungus. It lacks filamentous structure or hyphae.
Placentation in which ovules develop on the inner wall of the ovary or in peripheral part, is
In parietal placentation the ovules develop on the inner wall of ovary or in peripheral part. eg. Mustard, Argemone etc.
Which of the following is the most important cause for animals and plants being driven to extinction?
Habitat loss and fragmentation is the most important cause driving animals and plants to extinction.
eg: Loss of tropical rainforest reducing the forest cover from 14 % to 6 %.
Variations caused by mutation, as proposed by Hugo de Vries are
According to Hugo de Vries, mutations are random and directionless.
Devries believed mutation caused speciation and hence called saltation (single step large mutation).
Respiratory Quotient (RQ) value of tripalmitin is
In Antirrhinum (Snapdragon), a red flower was crossed with a white flower and in F1 generation pink flowers were obtained. When pink flowers were selfed, the F2 generation showed white, red and pink flowers. Choose the INCORRECT statement from the following :
Genes for flower colour in snapdragon shows incomplete dominance which is an exception of Mendel's first principle i.e. Law of dominance.
Whereas Law of segregation is universally applicable.
Select the INCORRECT statement.
In birds female heterogamety is found thus sex of progeny depends on the types of egg rather than the type of sperm.
The correct sequence of phases of cell cycle is
The cell cycle is a 4-stage process consisting of Gap 1 (G1), Synthesis, Gap 2 (G2) and mitosis. So, the correct sequence of phases of cell cycle is G1 → S → G2 → M
Thiobacillus is a group of bacteria helpful in carrying out
Thiobacillus denitrificans cause denitrification i.e., conversion of oxides of nitrogen to free N2.
Polyblend, a fine powder of recycled modified plastic, has proved to be a good material for
Polyblend is a fine powder of recycled modified plastic waste. The mixture is mixed with bitumen that is used to lay roads
From evolutionary point of view, retention of the female gametophyte with developing young embryo on the parent sporophyte for some time, is first observed in
In Pteridophyte, megaspore is retained for some times in female gametophyte, however the permanent retention is required for seed formation in Gymnosperms.
That's why Pteridophytes exhibit precursor to seed habit only.
Select the correct option.
-Vertebrosternal ribs are true ribs, dorsally they are attached to the thoracic vertebrae and ventrally connected to the sternum with the help of hyaline cartilage.
-First seven pairs of ribs are called true ribs.
-8th , 9th and 10th pairs of ribs do not articulate directly with the sternum but join the seventh ribs with the help of hyaline cartilage. These are vertebrochondral or false ribs.
-Last 2 pairs (11 & 12) of ribs are not connected ventrally and are therefore, called floating ribs.
-Only first seven pairs of ribs are ventrally connected to the sternum.
Concanavalin A is
Concanavalin A is a secondary metabolite e.g is lectin, it has the property to agglutinates RBCs.
Extrusion of second polar body from egg nucleus occurs :
Extrusion of second polar body from egg nucleus occurs after entry of sperm but before fertilization.
The entry of sperm into the ovum induces completion of the meiotic division of the secondary oocyte.
Entry of sperm causes breakdown of metaphase promoting factor (MPF) and turns on anaphase promoting complex (APC).
Pinus seed cannot germinate and established without fungal association. This is because :
Fungus associated with roots of Pinus increases minerals & water absorption for the plant by increasing surface area and in turn fungus gets food from plant. Therefore, mycorrhizal association is obligatory for Pinus seed germination
The Earth Summit held in Rio de Janeiro in 1992 was called
Earth Summit (Rio Summit)-1992, called upon all nations to take appropriate measures for conservation of biodiversity and sustainable utilisation of its benefits
DNA precipitation out of a mixture of biomolecules can be achieved by treatment with
During the isolation of desired gene, chilled ethanol is used for the precipitation of DNA.
Grass leaves curl inwards during very dry weather. Select the most appropriate reason from the following
Grass leaves curl inwards during very dry weather because of the flaccidity of bulliform cells. Water loss is the main cause of the curling. Bulliform cells become flaccid due to the water loss.
Match the following structures with their respective location in organs
Select the correct option from the following
-Crypts of Lieberkuhn are present in small intestine.
-Glisson's capsule is present in liver.
-Islets of langerhans constitutes the endocrine portion of pancreas.
-Brunner's glands are found in submucosa of duodenum.
Match the following hormones with the respective disease
Select the CORRECT option.
-Insulin deficiency leads to diabetes mellitus
-Hypersecretion or hyposecretion of thyroxine can be associated with enlargement of thyroid gland called goitre
-Deficiency of corticoids (Glucocorticoid + mineralocorticoid) leads to Addison's disease
-Growth hormone hypersecretion in adults leads to Acromegaly
Which of the following contraceptive methods do involve a role of hormone?
→ In lactational amenorrhoea, due to high prolactin level, gonadotropin level decreases.
→ Oral pills are either progestogens or progestogen-estrogen combinations used by the females.
→ Emergency contraceptives includes the administration of progestogens or progestogen-estrogen combination or IUDs within 72 hour of coitus.
So, lactational amenorrhoea, oral pills and emergency contraceptives involve a role of hormone.
Drug called ‘Heroin’ is synthesized by
Heroin, commonly called smack and is chemically diacetylmorphine which is synthesized by acetylation of morphine.
In a species, the weight of newborn ranges from 2 to 5 kg. 97% of the newborn with an average weight between 3 to 3.3 kg survive whereas 99% of the infants born with weight from 2 to 2.5 kg or 4.5 to 5 kg die. Which type of selection process is taking place?
The given data shows stabilising selection as most of the newborn having average weight between 3 to 3.3 kg survive and babies with less and more weight have low survival rate.
Conversion of glucose to glucose-6-phosphate, the first irreversible reaction of glycolysis, is catalyzed by
Hexokinase catalyse the conversion of Glucose to Glucose-6 phosphate. It is the first step of activation phase of glycolysis.
Which of the following statements is CORRECT?
Cornea consists of dense matrix of collagen and corneal epithelium. It is the most sensitive part of eye.
Which of the following ecological pyramids is generally inverted?
In an aquatic ecosystem, the pyramid of biomass is generally inverted.
Consider the following statement :
(A) Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group.
(B) A complete catalytic active enzyme with its bound prosthetic group is called apoenzyme.
Select the CORRECT option.
Coenzyme or metal ion that is tightly bound to enzyme protein is called prosthetic group. A complete catalytic active enzyme with its bound prosthetic group is called holoenzyme.
Due to increasing air-borne allergens and pollutants, many people in urban areas are suffering from respiratory disorder causing wheezing due to
Asthma is a difficulty in breathing causing wheezing due to inflammation of bronchi and bronchioles. It can be due to increasing air born allergens and pollutants. Asthma is an allergic condition. Many people in urban areas are suffering from this respiratory disorder.
Which one of the following statements regarding post-fertilization development in flowering plants is incorrect?
Following are the post-fertilisation changes.
-Ovule → Seed
-Ovary → Fruit
-Zygote → Embryo
-Central cell → Endosperm
Phloem in gymnosperms lacks :
Phloem in Gymnosperms lacks both sieve tube and companion cells.
It takes very long time for pineapple plants to produce flowers. Which combination of hormones can be applied to artificially induce flowering in pineapple plants throughout the year to increase yield?
Plant hormone auxin induces flowering in pineapple. Ethylene also helps in synchronization of flowering and fruit set up in pineapple.
Persistent nucellus in the seed is known as
Nucellus is the central tissue of ovules that contains the embryo sac. In some seeds like black pepper, it presists after the double fertilization. The persistent nucellus is called perisperm. It performs nutritive function.
e.g.: Black pepper, Beet
Cell in G0 phase :
Cells in G0 phase are said to exit cell cycle.
These are at quiescent stage and do not proliferate unless called upon to do so.
Match Column - I with Column - II
Choose the CORRECT answer from the option given below
-Saprophytes - Decomposition of dead organic materials
-Parasites - Grow on/in living plants and animals
-Lichens - Symbiotic association of algae and fungi
-Mycorrhiza - Symbiotic association of fungi with plant roots
What would be the heart rate of a person if the cardiac output is 5 L, blood volume in the ventricles at the end of diastole is 100 mL and at the end of ventricular systole is 50 mL?
Cardiac output = stroke volume × Heart rate
⇒ Cardiac output = 5L or 5000 ml
⇒ Blood volume in ventricles at the end of diastole = 100 ml
⇒ Blood volume in ventricles at the end of systole = 50 ml
Stroke volume = 100 – 50
= 50 ml.
So,
5000 ml = 50 ml × Heart rate
So, Heart rate = 100 beats per minute.
What triggers activation of protoxin to active Bt toxin of Bacillus thuringiensis in boll worm?