The quantity having the same units in all systems of units is
Time is the quantity having the same units in all system of units.
A balloon contains 1500 m3 of helium at 27°C and 4 atmospheric pressure. The volume of helium at -3°C temperature and 2 atmospheric pressure will be,
A police jeep is chasing a culprit going on a motorbike. The motorbike crosses a turning at a speed of 72 km/h. The jeep follows it at a speed of 90 km/h, crossing the turning 10 s later than the bike. Assuming that they travel at constant speeds, how far from the turning will the jeep catch up with the bike? (in km)
Given, vp = 90 km/hr = 90 x 5/18 m/sec = 25 m/sec
vc = 72 km/hr = m /sec = 20 m /sec
In 10 sec culprit reaches point B from A. Distance covered by culprit.
5 = vt =20 x 10=200m
At time t = 10 sec. The police jeep is 200 m behind the culprit. Relative velocity between jeep and culprit is 25 - 20 = 5 m /sec
[Relative velocity is considered]
In 40 sec, the police jeep will move from A to a distance S.
where, S = vt = 25 x 40 = 1000 m 1 km away
The jeep will catch up with the bike 1 km for from the turning.
What will b.e the force constant of the spring system shown in figure?
Two springs of force constants k1 and k1 are in parallel. Hence
k' = k1 + k1 = 2k1.
The third spring k2 is in series with spring of force constant R'.
A stone is tied to a string of length l and is whirled in air vertical circle with the other end of the string as their centre. At a certain instant of time, the stone is at its lowest position and has a speed u.The magnitude of the change in velocity as it reaches a position where the string is horizontal (g being acceleration due to gravity) is
When stone is at its lowest position, stone has only kinetic energy, given by k = 1/2 mu2
At the horizontal position, it has energy
According to conservation of energy.
K = E
⇒ u,2 = u2 - 2gl
So, the magnitude of change in velocity
If c, the velocity of light, g the acceleration due to gravity and P the atmospheric pressure, be the fundamental quantities in MKS system, then the dimensions of length will be same as that of
A particle of mass m is driven by a machine that deliver a constant power k watts. If the particle starts from rest the force on the particle at time t is
Fv = constant = k
A sonometer wire supports a 4 kg load and vibrates in fundamental mode with a tuning fork of frequency 416 Hz. The length of the wire between the bridges is now doubled. In order to maintain fundamental mode, the load should be changed to
Load supported by sonometer wire = 4 kg
Tension in sonometer wire = 4 g
If μ = mass per unit length
When length is doubled, i.e,, l' = 2l
Let new load = L
As, v' = v
A couple consisting of two forces F1 and F2 each equal to 5 N is acting at the rim of a disc of mass 2 kg and radius 1/2m for 5s. Initially, the disc is at rest, the final angular momentum of the disc is
Torque acting on disc is,
From angular impulse momentum theorem,
A large tank filled with water to a height 'h’ is to be emptied through a small hole at the bottom. The ratio of time taken for the level of water to fall from h to h/2 and h/2 to zero is
∴ t1 =
and t2 =
A body of mass m hangs at one end of a string of length l, the other end of which is fixed. It is given a horizontal velocity, so that the string would just reach where it makes an angle of 60° with the vertical. The tension in the string at bottom most point position is
Velocity at mean position,
= mg + mg = 2mg
What is the disintegration constant of radon, if the number of its atoms diminishes by 18% in 24 h?
For nuclear disintegration
A black body at 1227°C emits radiations with maximum intensity at a wavelength of 5000Å. If the temperature of the body is increased by 1000° C, the maximum intensity will be observed at
According to wien’x law, T = constant
Given, T = 1227 + 273 =1500 K.
T' = 1227 + 1000 + 273 = 2500 K.
λm = 5000 Å
Consider the following statement:
When jumping from some height, you should bend your knees as you come to rest, instead of keeping your legs stiff. Which of the following relations can be useful in explaining the statement?
Where symbols have their usual meanings.
If force acts for short interval Δt, then
The bandwidth of a series resonant circuit is 500 Hz and the resonant frequency is 5000 Hz. The quality factor of the circuit will be
The mass number of He is 4 and that for sulphur is 32. The radius of sulphur nuclei is larger than that of helium by
How much should the pressure of the gas be increased to decrease the volume by 10% at a constant temperature?
At constant temperature, PV = constant
As valume decreased by 10%, so pressure has to increase to keep the product of PV constant.
Therefore, volume becomes 9/10V
Pressure = 10/9 V
% increase =
A hollow cylinder has a charge q coulomb within it. If φ is the electric flux in units of voltmeter associated with the curved surface B, the flux linked with the plane surface A in units of voltmeter will be
Since φtotal = φA + φB + φC = q/ε0,
where q is the total charge.
As shown in the figure, flux associated with the curved surface B is φ = φB
Let us assume flux linked with the plane surfaces A and C be
φA = φC = φ'
The equation y = represents a wave with
Now, general wave equation is
y = A cos (ωt - kx)
= A cos(2πvt - (2π/λ)x) ...(ii)
On comparing Eqs. (i) and (ii), we get
Amplitude - A/2, frequency v =2n
and wavelength = λ/2
If the critical angle for total internal reflection from a medium to vacuum is 30°. Then velocity of light in the medium is
Velocity of light in the medium.
= 1.5 x 108 m/sec
Which of the following is not the property of equipotential surfaces?
They can be imaginary spheres.
The rain drops are in spherical shape due to
Rain drops are in spherical shape due to surface tension.
A parallel plate capacitor is connected to a battery. The plates are pulled apart with a uniform speed. If x is the separation between the plates, the time rate of change of electro static energy of capacitor is proportional to
Energy of a parallel plate capacitor is given by
Given that, d = x
Therefore, we have U =
Potential energy decreases as =
A particle of mass 1 kg is moving in S.H.M. with an amplitude 0.02 and a frequency of 60 Hz. The maximum force acting on the particle is
Max. force = mass x max. acceleration
= m 4 π2 v2 a = 1 x 4 x π2 x (60)2 x 0.02
A long horizontal rod has a bead which can slide along its length and initially placed at a distance L from one end A of the rod. The rod is set in angular motion about A with constant angular acceleration α. If the coefficient of friction between the rod and the bead is μ and gravity is neglected, then the time after which the bead starts slipping is
Bead starts moving when the centripetal force is equal to the friction.
Hence, friction F = μmat [here gravity is neglected]
where, at is tangential acceleration, it will be given by
at = v/t, where v is the linear speed = Lω.
Also, centripetal farce = mLω2
According to Maxwell’s hypothesis, a changing electric field gives rise to
Changing electric field gives rise to displacement current which creates magnetic field around it.
Which of the following pairs of space and time varying E = (iEx + jEY + kEz) and B = (iBx + jBy + kBz) would generate a plane electromagnetic wave travelling in the z-direction?
Direction of propagation of EM waves is in the direction of cross product of E and B [i. e. E x B]
So, if wave is propagating in two direction, then
E = Exi and B = Byj
Then, E x B point in +z direction.
A bucket full of hot water is kept in a room and it cools from 75°C to 70°C in T1 minutes, from 70°C to 65°C in T2 minutes and from 65°C to 60°C in T3 minutes. Then
The time of cooling increases as the difference between the temperature of body 6 surrounding is reduced. So T1<T2<T3 (according to Newton’s law of cooling).
In Young’s double slit experiment, when wavelength used is 6000 Å and the screen is 40 cm from the slits, the fringes are 0.012 cm wide. What is the distance between the slits?
The energy of hydrogen atom in the nth orbit is En, then the energy in the nth orbit of single ionised helium atom is
For nth orbit, energy,
For hydrogen (z = 1),
For helium (z = 2),
Photo cathodes of work functions 3 eV and 1.5 eV, The incident light has energy 4.5 eV, then the ratio of maximum velocities of the two are
Required ratio =
A cubical block of side 30 cm is moving with velocity 2 ms-1 on a smooth horizontal surface. The surface has a bump at a point O as shown in figure. The angular velocity (in rad/s) of the block immediately after it hits the bump, is
Angular momentum, mvr = lω
Moment of Inertia (I) of cubical block is given by
The resistivity of an n-type extrinsic semiconductor is 0.25Ω - m . If the electron mobility is 8.25 m2/V-s, then the concentration of donor atoms will be (in m-3)
= 3.0 x 1018m-3
Four particles of masses m1,m2,m3 and m4 are placed at the vertices A, B, C and D as respectively of a square shown. The COM of the system will lie at diagonal AC if
The binding energy of a H-atom, considering an electron moving around a fixed nuclei (proton), is (m = electron mass)
If one decides to work in a frame of reference where the electron is at rest, the proton would be moving around it.
By similar arguments, the binding energy would be
This last expression is not correct because
The current in a coil of L = 40m H is to be increased uniformly from 1A to 11A in 4 milli sec. The induced e.m.f. will be
A physical quantity is given by X = [MaLbTc]. The percentage error in measurements of M, L and T are α, β and y. Then, the maximum % error in the quantity X is
Maximum possible % error is Δx/x x 100 = aα + bβ + cy
Time required to boil 2 litres of water initially at 20°C by a heater coil which works at 80% efficiency spending 500 joule/s is
Heat required to boil water = mcΔq
= 2 x 4200 x (100 - 20)
= 6.72 x 103J
If t be the time of boil then
η x 500 x t = 6.72 x 103
A car is moving towards a high cliff. The car driver sounds a horn of frequency f. The reflected sound heard by the driver has a frequency 2f. If v be the velocity of sound then the velocity of the car, in the same velocity units will be
When the sound is reflected from the diff, it approaches the driver of the car. Therefore, the driver acts as an observer and both the source (car) and observer are moving.
Hence, apparent frequency heard by the observer (driver) is given by
Where, v = velocity of sound,
v0 = velocity of car = vs
Thus, equn(i) becomes
⇒ 2v - 2v0 = v + v0
⇒ 3v0 = v
⇒ v0 = v/3
A ray of light is incident on the surface of separation of a medium with the velocity of light at an angle 45° and is refracted in the medium at an angle 30°. Velocity of light in the medium will be (velocity of light in air = 3 x 108 m/s)
Velocity of light in medium
The focal length of a lens for red and violet colours are 16.4 cm and 16 cm. What is its dispersive power?
= 0.4/16 = 0.025
Which of the following statements is FALSE for a particle moving in a circle with a constant angular speed?
Acceleration vector is always radial (i.e. towards the center) for uniform circular motion.
A T shaped object with dimensions shown in the figure, is lying on a smooth floor. A force F is applied at the point P parallel to AB, such that the object has only the trasnlational motion without rotation. Find the location of P with respect to C
Two monkeys of masses 10 kg and 8 kg are moving along a vertical rope which is light and inextensible, the former climbing up with an acceleration of 2m/s2 while the latter coming down with a uniform velocity of 2m/s. Find the tension (in newtons).
T = T1 + T2 = m1(g+a) + m2g
= 10(10 + 2) + 8 (10) = 120 + 80 = 200 N
If force (F), velocity (v) and time (T) are taken as fundamental units, then the dimensions of mass are
F = [MvT-1]
M = [ F-1vT]
The isotopic abundance of C-12 and C-14 is 98% and 2% respectively. What would be the number of C-14 isotope in 12 g carbon sample?
Weight of C-14 isotope in 12 g sample = (2 x 12)/100
Number of C -14 isotope =
= 1.032 x 1022 atoms
The amount of arsenic pentasulphide that can be obtained when 35.5 g arsenic acid is treated with excess H2S in the presence of conc. HCI (assuming 100% conversion) is:
∴ number of moles of H3AsO4 = 35.5/142 = 0.25
∴ number of moles of As2S5
= 0.25/2 = 0.125 mole.
Which of the following oxides is amphoteric in character?
CO2 - acidic
SiO2 - weakly acidic
SnO2 - amphoteric
Which property of white phosphorus is common to red phosphorous?
Except (a) all other properties are shown by white phosphorous.
50 mL of each gas A and gas B takes 150 and 2008 respectively for effusing through a pin hole under the similar conditions. If molecular mass of gas B is 36, the molecular mass of gas A will be
Given, VA = VB = 50 mL, tA = 150s, tB = 200s
from Graham’s law of effusion
In sodium fusion test of organic compounds, the nitrogen of the organic compound is converted into
Sodium cyanide (Na + C + N → NaCN). (Lassaigne's test)
Calculate enthalpy for formation of ethylene from the following data
I. C(graphite) + O2(g) → CO2(g); ΔH = - 393.5 kJ
II. H2(g) + 1/2 O2(g) → HO2(l); ΔH = -286.2 kJ
III. C2H4(g) + 3O2(g) → 2CO2(g) + 2H2O(l);
ΔH = -1410.8 kJ
C + O2 → CO2; ΔH = -393.5KJ ...(i)
H2 + (1/2) O2 → H2O; ΔH = -286.2 ...(ii)
C2H4 +3O2 → 2CO2 + 2H2O; ΔH = -1410.8KJ ...(iii)
Multiplying the eqs (i) and (ii) by 2
2C + 2O2 → 2CO2; ΔH = -787.0 KJ ...(iv)
2H2 + O2 → 2H2O; ΔH = -572.4KJ ...(v)
On adding eqs (iv) and (v) and then substract (iii)
2C + 2H2 → C2H4; ΔH = 51.4KJ
Inductive effect involves
Inductive effect involves displacement of σ-electrons.
Which of the following, the oxidation number of oxygen has been arranged in the increasing order?
Let the oxidation number of oxygen in the following compounds be x.
In OF2 x + (-1)2 = 0
x = +2
In KO2 + 1 + (x x 2) = 0
2x = -1, x = -1/2
In BaO2 + 2 + (x x 2) = 0
2x = -2, x = -1
In O3, oxidation number o f oxygen is zero because oxidation number of an element in free state or in any of its allotropic form is always zero.
Thus, the increasing order of oxidation number is
Aluminium vessels should not be washed with materials containing washing soda since
Washing soda reacts with Al to form soluble aluminate
2Al + Na2CO3 + 3H2O → 2NaAlO2 + CO2 + 3H2
Each of these questions contains two statements: Assertion and Reason. Each of these questions also has four alternative choices, only one of which is correct Answer. You have to select one of the codes (a), (b), (c) and (d) given below.
(a) Assertion is true, Reason is true; Reason is a correct explanation for Assertion
(b) Assertion is true, Reason is true; Reason is not a correct explanation for Assertion
(c) Assertion is true, Reason is false
(d) Assertion is false, Reason is true
Assertion A buffer solution has a capacity to resist the change in pH value on addition of small amount of acid or base to it.
Reason pH value of buffer solution does not change on dilution or on keeping for long.
If a strong acid is added, the H+ ions added neutralised by the base. If a strong base is added, the OH- ions added are neutralized by cation forming very slightly dissociated base. Thus, the pH of buffer is reserved.
Which of the following reagents convert propene to 1-propanol?
We know that
Glauber’s salt is
1 M solution of CH3COOH should be diluted to .......... times so that pH is doubled.
pH' (twice of pH) = pKa
A commercial sample of hydrogen peroxide is labelled as 10 volume. Its percentage strength is nearly
Percentage strength = 17/56 x Volume strength
= (17/56) x 10 = 3.03% ≈ 3%
Which one of the following is NOT a buffer solution?
Buffer solution contains weak base + salt of weak base with strong acid or weak acid + salt of weak acid with strong base.
In option (d) the acid used is HCIO4 which is strong acid and KCIO4 is salt of this acid with strong base. So it is not an example of buffer solution.
2-hexyne gives trans-2 -hexene on treatm ent with
Which one of the following is expected to exhibit optical isomerism?
(en = ethylenediamine)
Toluene reacts with excess of Cl2 in the presence of sunlight to give a product which on hydrolysis followed by the reaction with NaOH give
The unpaired electrons in Ni(CO)4 are
Ni(CO)4. The O.S. of Ni is zero. Electronic configuration is [Ar] 3d8 4s2 4p°. In presence of strong ligand CO the paring of electrons take place and electronic configuration will be [Ar] 3d10 4s° 4p°.
Hence unpaired electrons is zero.
A mixture of ethane and ethene occupies 41 L at 1 atm and 500 K, the mixture reacts completely with 10/3 mole of O2 to produce CO2 and H2O. The mole fraction of ethane and ethene in the mixture are
(R = 0.0821 L atm K-1 mol-1) respectively
PV = nRT ⇒ 1 x 41 = n x 0.821 x 500
n = 0.998 mol
The number of moles of ethane = x
So, number of moles of ethane = (0.998 - x)
Reaction of ethane and ethane with O2
(i) 2C2H6 + 7O2 → 4CO2 + 6H2O
(ii) C2H4 + 3O2 → 2CO2 + 2 H2O
According to (i) reaction
∵ 2 moles ethane react w ith 7 moles of O2
∴ x moles ethane react with 7x/2 moles of O2
According to (ii) reaction
∵ 1 mole ethene reacts with 3 moles of O2
∴ (0.998 - x) mole ethene reacts = 3(0.998 - x) mole of O2
Mole of ethene = 0.998 - 0.678 = 0.32
Identify the reaction which does not liberate hydrogen :
Lithium hydride react with diborane to produce tithiumborohydride.
2LiH + B2H6 → 2 LiBH4
For the reduction of silver ions with copper metal, the standard cell potential was found to be +0.46 V at 25°C. The value of standard Gibbs energy, ΔG° will be (F = 96500 C mol-1)
We know that
Standard Gibbs energy, ΔG° = -nFEcell for the cell reaction,
2Ag+ + Cu → Cu2+ + 2Ag
ΔG°= - 2 x 96500 x 0.46
= -88.7kJ ≈ -89.0kJ
When concentrated HCl is added to an aqueous solution of CoCl2, its colour changes from reddish pink to deep blue. Which complex ion gives deep blue colour in this reaction?
A queous solution of CoCl2 contains [Co(H2O)6]2+ which is pinkish in colour so option (d) is incorrect.
Reduction potential of Co3+ → Co2+ is high so option(b) is incorrect. Co2+ does not oxidises easily to Co3+.
It is general case that symmetrical substituted octahedral complexes are less deeper in colour than tetrahedral complexes.
So [CoCI4]2- is deep blue in colour.
The rate law for the chemical reaction 2NO2Cl → 2 NO2 + Cl2 is rate = K [ NO2Cl] The rate determining step is
Rate = K[NO2Cl]
Hence, rate determining step is
2NO2Cl → 2NO2 +.2Cl
The number of enantiomers of the compound CH3CH(Br)CH(Br)COOH is:
No. of asymmetric carbon = 2
No. of enantiomers = 22 = 4.
At high pressure, Langmuir adsorption isotherm takes the form
Langmvir adsorption isotherm is
At higher pressure, 1 + bp = bp
Which of these have no unit?
Electronegativity is the tendency of the atom to attract electrons to itself when combined in a compound as defined by Pauling. Electronegativity is a relative term so it does not have any unit.
Two concentration cells of Ag with Ag electrode in AgNO3. In first cell, concentration of one electrode is 1 M and other electrode is 0.1 M and emf is 0.06 V. In second cell, concentration of one electrode is 1 M and other electrode is 0.01 M, calculate the emf of second cell.
Dividing Eq. (i) by Eq. (ii), we have
(Ecell)2 = 2 x 0.06
= 0.12 V
The reactivity of metals with water is in the order of
The reactivity may be attributed to size factor, larger is the size, higher is tendency to lose electron (low I.E.). Zn can displace iron and copper according to reactivity series. So, Zn is more reactive than iron and copper. Hence, the reactivity order is Na > Mg > Zn > Fe > Cu.
Which of the following reaction is an example of calcination process?
The process of conversion of a concentrated ore into its oxide by heating in absence or in limited supply of air is called calcination. It is usually done for hydroxide and Carbonate ores.
Thus, MgCO3 MgO + CO2 is an example of calcination process.
In Cannizzaro reaction given below 2PhCHO PhCH2OH + PhCO-2 the slowest step is:
Of the following outer electronic configurations of atoms, the highest oxidation state is achieved by which one of them?
The rapid change of pH near the stoichiometric point of an acid base titration is the basis of indicator detection. pH of the solution is related to ratio of the concentrations of the conjugate acid (Hln) and base (In- ) forms of the indicator by the expression
For an acid-base indicator
Taking negative on both sides
or we can write
Transition metals usually exhibit highest oxidation states in their
Transition metals show their highest oxidation states in their fluorides due to small size and higher electroneg-ativity of ‘F'.
In lake test of Al3+ ion, there is formation of coloured floating lake. It is due to
In lake test of Al3+, there is formation of coloured floating lake. It is due to the adsorption of litmus by Al(OH)3.
Which of the following compounds is aromatic alcohol?
aromatic alcohols due to the presence of benzene ring and -OH group is attached with aliphatic carbon.
Which of the following fact(s) explain as to why p-nitrophenol is more acidic than phenol?
(i) - I Effect of nitro group
(ii) Greater resonance effect of p-nitrophenoxy group.
(iii) Steric effect of bulky nitro group.
In the following reaction, product (A) is
Major product is formed by para-attack.
Which of the following shows iso-structural species?
NH4+ have sp3 hybridisation(with tetrahedral geometry) and NH2- are having sp2 hybridisation(with angular geometry). So they won't have the same shape.
CH3- has sp3 hybridisation(tetrahedral) while CH3+ has sp2 hybridisation(trigonal planar).
SO42-, PO43- and BF4- all are tetrahedral.
NH4+ is tetrahedral while NH3 is pyramidal.
Teflon polymer is formed by the polymerisation of
(a) CH2 = CH - CN (acrylonitrile) polym erises to form PAN.
(b) CH2 = CHCl (vinyl chloride) polymerises to form PVC.
(c) F2C = CF2 (tetrafluoro ethylene) polymerises to form teflon.
The Langmuir adsorption isotherm is deduced using the assumption
Langmuir adsorption isotherm is based on the assumption that every adsorption site is equivalent and the ability of a particle to bind there is independent of whether or not nearby sites are occupied.
The best reagent to convert pent-3-en-2-ol into pent-3-en-2-one is
= CH — CH3
Pyridinium chloro chromate (PCC) oxidises an alcoholic group selectively in the presence of carbon-carbon double bond.
Match the columns
Argyrol is used as an eye lotion.
Antimony is used in Kalazar.
Colloidal gold is used in intramuscular injection.
Milk of magnesia is used in the stomach disorder.
One gram of a monobasic acid when dissolved in 100 g of water lowers the freezing point by 0.186° C Now, 0.25 g of the same acid is dissolved and titrated with 15.1 mL of N/10 alkali. The degree of dissociation of the acid is (kf for H2O = 1.86)
W = (ENV/1000) [for monobasic acid, E = M]
Molality (m) =
ΔTf = kf x m = 1.86 x 0.060 = 0.1116
At equilibrium 1 - x x x
⇒ 1.66 = 1 + x
⇒ x = 0.66
Somatic hybridisation is the fusion of two protoplasts by Polyethylene Glycol (PEG). The separation of protoplast is done by treating cells with
In Somatic hybridisation Various enzymes take part in the protoplasmic fusion by Polyethylene Glycol (PEG). Those enzymes are pectinase and cellulase enzymes.
Which of the following group of animals belongs to the same phylum?
Prawn, scorpion and Locusta belong to phylum Arthropoda. Arthropoda is the largest phylum of animalia, and includes the insects arachnids, crustaceans and others. It is a group of animals with features including bilaterally symmetrical, triploblostic tube within tube plan, organ system level of organisation and metemerically segmented body.
Identify the correct relationship with reference to water potential of a plant cell.
water potential of a plant cell is
ψw = ψm + ψs + ψp
Which one of the following is a true fruit?
The fruit is a mature or ripened ovary. When a fruit develops exclusively from the ovary, it is said to be true fruit. When in addition to the ovary, some other floral part also participates in the formation of fruits, then it is known as false fruit. Apple, pear, cashewnut, mulberry etc. are all false fruits.
Match the following columns.
A. Transferases 4. Pyruvate Carboxylase enzyme
B. Lyases 1. Histadine decarboxylases enzyme
C. Hydrolases 3. Glutamate Pyruvate transaminas
D. Ligase 4. Amylase
Mendel selected pea as material for his experiments because
Choose the correct option.
A multiple fruit or composite fruit develops from an entire inflorescence i.e., from a cluster or group of flower into an entire fruit, e.g. pineapple, Mulberry, Osage-Orange etc.
Which of the following statements is incorrect for sickle cell anaemia?
Among the following which microorganism respire anaerobically under normal conditions?
Rhodopseudomonas faecalis is a gram-negative, anaerobic, phototrophic microorganism.
In a fertilised ovule, n, 2n and 3n conditions occur respectively in
In a fertilised ovule, n, 2n and 3n conditions occur respectively in egg, nucellus and endosperm.
The biofertiliser, which is inoculated in rice fields in South-Eastern Asia, which is found to increase yield up to 50%, is
Anabaena azollae i.e., present in the leaves of water fern (Azolla) used as a biofertiliser, that increased the production of rice in agricultural fields.
From megasporocyte to egg cell, what processes are required?
Who is credited with identifying petro-crops?
Petroleum plants or Petro-crops significantly described by Dr. M. Calvin in 1979 in the university of California, who understand the petroleum plants demand i.e. energy gaining plants and rich of hydrocarbons.
Match the column-I with column-II and choose the correct option.
A - Fibres: Fibres are thick-walled, elongated and pointed cells, generally occurring in groups, in various parts of the plants.
B - Sclereids: Sclereids are thick-walled hgnified sclerenchyma cells. Sclereids are variable in shape and are shorter than fibres.
C - Tracheids: Tracheids are the ancient tracheary elements and the main water- conductive cells of the pteridophytes and the gymnosperms. They are elongated cells with tapering ends. Their cell [walls characteristically bear spiral (pteridiophytes), pitted or bordered-pitted (gymnosperms) thickening. Water moves from cell to cell through the side walls.
D - Vessels: Vessel is a long cylindrical tube like structure made up of many cells called vessels members.
E - Xylem parenchyma: Xylem parenchyma cells are living and thin-walled and their cell walls are made up of cellulose. They store food materials in the form of starch or fats and other substances like tannins.
Which of the following characteristics is mainly responsible for diversification of insects on land?
Diversification of insects can be differendate by their shape, colour and structure like their exoskeleton that is the mainly responsible known characteristic for diversification.
If the gene encoding the trp repressor is mutated such that it can no longer bind tryptophan, Will transcription of the trp operon occur?
If there pressor can no longer bind tryptophan, then it cannot bind the operator and transcription of the trp operon will always be on, whether tryptophan levels in the cell high or low.
A terrestrial animal must be able to
A terrestrial animal must be able to conserve water.
Telomerase is an enzyme which is a
Telomerase is a ribonucleoprotein which synthesises the G rich strand of telqmeres in DNA. It adds specific DNA sequence repeats in all vertebrates to the 3' end of DNA strands in the telomere regions, which are found at the ends of eukaryotic chromosomes. The telomeres contain condensed DNA material, giving stability to the chromosomes. The enzyme is a reverse transcriptase that carries its own RNA molecule, which is used as a template when it elongates telomeres, which are shortened after each replication cycle. Telomerase was discovered by Carol W. Greiderin 1984.
The membranous cover of the ovum at ovulation is
Corona radiata is a membranous covering of the Ovum which shows during the time of Ovulation.
The Triticale is an intergeneric hybrid between:
Triticale is a man made hexaploid inter generic hybrid.
A individual has low blood potassium and hypertension. Blood investigations show that has blood aldostem very high. He might be suffering from
Excess production of the hormone aldosterone by the adrenal glands called as primary aldosteronism or Conn’s disease.
Which group contains animals that are not pseudocoelomate?
Which communities are more vulnerable to invasion by outside plants and animals?
A tropical rainforest has the highest diversity of plants and animals. These plants and animals have evolved to maintain the ecological balance of forest ecosystem as a community. Also, because of highest resources available in rainforests, they are more susceptible to invasion by outside animals and plants. Any alien species invasion is going to disturb this balance of forest ecosystem.
The mode of catching insects in Drosera plants is by means of
For its action,nitrogenase requires
For high input of energy, nitrogenase requires for its action in a catabolic and anabolic reactions.
What is the minimum number of cell membranes that a water molecule must move through in getting from the soil into a xylem vessel element?
Water could travel to the endodermis layer via apoplast, then passes through the outer endodermis cell membrane, and enters the stele through apoplast by diffusing through the inner endodermis membrane.
Select the wrong statement.
Oomycetes are microscopic, absorptive and filamentous organism that reproduce both sexually and asexually. The Structure of female gamete is larger round shaped and non-motile while male gamete is smaller and motile. Oomycetes is the example of Coenocytic Mycelium, that reproduce in zygospore/zygote/oospore.
Operon is a
Operons are segments of genetic material (DNA) which functions as regulated unit or units that can be switched on or switched off. It is a sequence of closely placed genes regulating a metabolic path way in prokaryotes.
Pteridophytes were well adapted and advanced for survival on land but they cannot be much successful and widespread as gymnosperms and angiosperms because they lack
As pteridophytes were well adapted and advanced but these plants less sucessful and widespread as gymnosperms and angiospermic plants because they lack freedom from water for fertilisation.
Krebs cycle occurs in
The enzyme involved in Krebs’ cycle are localised in the mitochondrial matrix.
Root-pockets are present in
In Pandamus multiple root caps are present while in aquatic plants (pistia, Eichhomia and Lemna) root pockets are present i.e., a Sac like Structure found in some aquatic plants.
An inhibitor is added to a cell culture so that succinate accumulates. The enzyme catalysing the formation of which substance has been blocked?
During Krebs' cycle, fomarate is formed from succinate and hence synthesis of fumarate is blocked.
What type of spores are in bryophytes?
Bryophytes indudes Various mosses and liver worts. They lack true roots, Stem or leaves, The main plant body of biyophyte is haploid (Single number (n)).
The amount of DNA in a mammalian cell in early prophase I is x. What is the amount of DNA in the same cell in anaphase I of meiosis?
At prophase I, DNA replication has already occurred, and the original amount of DNA has been doubled, to x. At anaphase I, the amount of DNA in the cell remains the same because no cytokinesis has occurred yet to separate the cytoplasm.
Growth in living things occur due to synthesis of
In living Organisms or things growth occurs due to the synthesis of protoplasmic and apoplasmic Substances i.e. liquid Substance found intra-cellular Nucleus.
Match column-I with column-II and select the correct answer using the codes given below.
A mammalian ovum fails to get fertilised, which one of the following is unlikely?
A) Estrogen secretion further decreases- Estrogen is secreted by the corpus luteum. Since it disintegrates in the absence of fertilization, estrogen levels fall.
B) Progesterone secretion starts declining- If pregnancy occurs, human chorionic gonadotropin is released maintaining the corpus luteum allowing it to maintain levels of progesterone. In the other way round, (i.e., in case of fertilization does not occur), progesterone levels fall due to the disintegration of the corpus luteum.
C) Corpus luteum will disintegrate- If the egg is not fertilized, the corpus luteum stops secreting progesterone and decays (after approximately 14 days in humans). It then degenerates into a corpus Albicans, which is a mass of fibrous scar tissue.
D) Primary follicle starts developing- Primary follicle is a precursor to the corpus luteum and thus this is most unlikely to happen. At the start of the menstrual cycle, some 12-20 primary follicles begin to develop under the influence of elevated FSH to form secondary follicles. The primary follicles have formed from primordial follicles, which developed in the ovary at around 10-30 weeks after conception.
So, the correct answer is option D.
Match column-I with column-II and identify the correct option.
A : Hind III is a type II site-specific restriction enzyme isolated from Haemophilus influenzae.
B : Transposons (also called jumping genes) are DNA sequences that can change their position within a genome.
C : Bacteriophage is a virus which parasitises a bacterium by infecting it and reproducing inside it. They can also be used as cloning vectors.
D : Palindrome is a segment of double- stranded DNA in which the nucleotide sequence of one strand reads in reverse order to that of the complementary strand, e.g., MALAYALAM.
Following statements are given regarding MTP.
Choose the correct options given below
I. MTPs are generally advised during first trimester
II. MTPs are used as a contraceptive method
III. MTPs are always surgical
IV. MTPs require the assistance of qualified medical personnel
MTPs are Medical Termination of Pregnancy. MTPs are Safe during first trimester (up to 12 weeks of pregnancy) after that MTPs are riskier. MTPs require the assistance of qualified medical personnel. MTPs are not Surgical and used as a abortive method.
Select false statements for an enzyme promoting a chemical reaction by
(i) Lowering the energy of activation.
(ii) Causing the release of heat, which acts as a primer.
(iii) Increasing molecular motion.
(iv) Changing the free energy difference between substrate and product.
Enzymesarebiologicalmolecules(proteis) that act as catalysts and help complex reactions occur. Enzymes bind temporarily to one or more of the reactants the substrate(s) of the reaction they catalyse by lowering the amount of activation energy needed and thus speed up the reaction.
Which of the following gametes are produced by individual with geno type AaBb?
There are four possible combinations of gametes for the AaBb parent. Half of the gemetes get a dominant A and a dominant B allele, the other half of the gametes get a recessive a and a recessive b allele.
Which of the following pair is correctly matched?
Pair of anaphase I with its feature is correctly matched.
Metaphase I: Spindle apparatus appear and the chromosomes are arranged on equatorial plate, with the centromeres towards the pole. Spindle fibres become attached to the centromeres of the two homologous chromosomes.
Interphase: It is the time during which cell is preparing for division by undergoing both cell growth and DNA replication.
Prophase I: It is the lengthy phase when compared with mitotic phase . It is subdivided into 5 sub-phases: leptotene, zygotene, pachytene, diplotene and diakinesis.
Classification given by Bentham and Hooker is
Natural Classification based on overall Similarities in morphology, anatomy etc. This classification given by Bantham and Hooker.
Which of the above is Zwitterionic form?
The greatest biomass of autotrophs in the world’s oceans is that of
Free-Floating micro-algae, cyanobacteria (blue green algae) and nanoplankton are widely present in Ocean.
Sex factor in bacteria is
Sex factor or F-factor in bacteria results ir high frequency conjugation. It allow bacteria to produce sex pilus necessary for conjugation.
The eyes of the potato tuber are
So the correct option is "Axillary buds".
Read the following statements (i - iv) and accordingly mark the option that has both correct statements.
(i) Cardiac fibres are branched with one or more nuclei.
(ii) Smooth muscles are unbranched and cylindrical.
(iii) Striated muscles can be branched or unbranched.
(iv) Involuntary muscles are non-striated
Smooth muscles are not branched and cylindrical in appearance. Involuntary muscles are striated.
Generally epidermis is single layered but in certain leaves, multilayered upper epidermis is present such as
Nerium, Ficus, Pepromea in these certain leaves epidermis present in various or multi layers that function to protect all important nutritive and stomatal product.
Given below are four matchings of an'animal and its kind of respiratory organ.
(i) Silverfish - trachea
(ii) Scorpion - book lung
(iii) Sea squirt-pharyngeal gills
The correct matchings are:
Dolphin is an aquatic mammal and breathes through lungs.
The correct statement is
Viruses are non-cellular microrganisms. It contain either DNA or RNA as nudeic acid or as their genetic material. In Various Plant Viruses genetic material may be single Stranded (ss) RNA while animal viruses have either single or double stranded RNA or double stranded DNA. Bacteriophages are usually doubl stranded DNA Viruses.
Which one of the following characters is not typical of the class Mammalia?
Mammals have 12 pairs of cranial nerves.
The movement of solutes in the phloem is mainly
Besipetal of leaves or flowers are the developing or opening Succession from apex base which helps the movement of solutes and other necessary particles. Thus movement of Solutes in the phloem is mainly by Besipetal.
Consider the statements given below regarding contraception and answer as directed thereafter:
(i) Medical Termination of Pregnancy (MTP) during first trimester is generally safe.
(ii) Generally chances of conception are nil until mother breast-feeds the infant upto two years.
(iii) Intrauterine devices like copper-T are effective contraceptives.
(iv) Contraception pills may be taken upto one week after coitus to prevent conception.
Which two of the above statements are correct?
Statements (i) and (iii) are correct.
- Medical Termination of Pregnancy (MTP) during first trimester is generally safe.
- Intrauterine devices like copper-T are effective contraceptives.
In pteridophytes, spores germinate to give rise in inconspicuous, small multicellular, free living photosynthetic, thalloid gametophyte called
The main plant of Pteridophytes are sporophytes. They reproduce asexually by forming spores in sporangia. The plants may be homosporous, i.e., produce only one type of spores (e.g., Lycopodium, Pteridium) or heterosporous i.e., produce two different types of spores, smaller microspores and larger megaspores (e.g., Selaginella, Marsilea etc.).
The spores germinate to produce haploid gametophyte, called as prothallus. The homosporous Pteridophytes produce bisexual (monoecious) gametophytes, whereas heterosporous one produce unisexual (dioecious) gametophytes.
Which pathway of the male reproductive system is correct for the sperms transportation?
Epididymis lies between vasa effersntia and vas deferens.
Structure protecting archegonia of Marchantia
The archegonia of Marchantia has a short but distinct stalk. There is a collar like Structure at the base of the Venter of each archegonium called Perigynium. Two-lipped Curtain like Structure i.e. perichaetium protects archegonia of Marchantia.
A force acting against achievement of highest possible level of population growth is
A force which acts against the achievement of highest possible level to population growth is known as Environmental resistance.
The environment can effectively limit or control population growth by altering birth and death rates in the ecological system.
Some of the vitals factors affecting population growth are disease, predators, food, competitors, and some of the abiotic factors include flood, cyclones, temperature, rainfall, etc.
Central dogma of modem biology is
Central dogma of modern biology is
DNA → RNA → Protein
Which of the following pair of match is not correct?
An unifying principle of cellular energetics, is
The actual production of ATP in cellular respiration takes place through the process of Chemiosmosis that allows our body to make energy.
Haemophilia is more common in males because it is a
Haemophilia is a sex linked recessive trait carried by X chromosome (also known as bleeder’s disease).
In which cell of leaf, pyruvate is converted to PEP in C4 pathway?
Carbon dioxide fixation occurs twice in C4 plants, first in Mesophyll cells then in bundle Sheath cells. Here is Carbon dioxide fixing enzyme is PEP Carboxylase, which is very efficient in C4- plants.
Match column-I with column-II and select the correct answer using the codes given below.
The law of limiting factors was proposed with particular reference to photosynthesis. Identify the scientist, who proposed this law?
The biosynthetic phase of photosynthesis, does not directly depend on the presence of light but is dependent on the products of the light reaction also known as dark reaction this law called law of limiting factors was proposed by FF Blackman in 1905.
Sphincter of Oddi controls the flow of digestive juice by guarding which duct?
Hepato-pancreatic duct (marked as 3) is guarded by sphincter of Oddi. The sphincter of Oddi (or Hepatopancreatic sphincter) is a muscular valve that controls the flow of digestive juices (bile and pancreatic juice) through the ampulla of Water into the second part of the duodenum.
Which one is true about guttation?
Guttation refers to the exudation of water droplets (in the form of Salt Solution) from the margins and tips of leaves. Guttation water is exuded from the group of leaf cells through specialized opening or pores called hydathodes.
Pacemaker of heart is
Sino-atrial node (SA node) present in the walls of right auricle has a myogenic initiation of heartbeat in a regular fashion and controls the pace of heartbeat and is called pacemaker.
In C3 cycle for the fixation of every CO2 molecules, the reduction and regeneration steps required
In C3 Cycle, for the fixation of every CO2 molecules the reduction and regeneration steps require 3 ATP molecules and 2 Molecules of NADPH2 that supply assimilatory power and purifies the atmospheric air.
In meiosis, actual haploidy in terms of DNA comes in
One gene-one enzyme relationship was established for the first time in
The one gene-one enzyme hypothesis, proposed by George wells Beadle in the United State. Beadle and Tatum first Created Neurospora mutants by irradiating Neurospora with X-ray.
The diagram below summarises the stages involved in respiratory metabolism of mammalian skeletal muscle.
Stage 4 in the diagram occurs in mammaliar muscle cells under anaerobic conditions. Why is stage 4 necessary?
The conversion of pyruvate to lactate is anaerobic respiration, where the NADH2 is oxidised and the energy used in stage 2.
Foetal ejection reflex in human female is induced by
Foetal ejection reflex. -
The signals for parturition originate from the fully developed foetus and the placenta which induce mild uterine contractions called foetal ejection reflex.
This triggers release of oxytocin from the maternal pituitary. Oxytocin acts on the uterine muscle and causes stronger uterine contractions, which in turn stimulates further secretion of oxytocin.
The nerve centres which control the body temperature and the urge for eating are contained in: