727 + Interview Questions in GENERAL QA IN NEET Page 9 InterviewSolution

401.	During melting of an ice slab at 273 K at atmospheric pressure (a) positive work is done by ice water system on teh atmosphere (b) positive work is done on ice water system by the atmosphere (c) internal energy of ice water system decreases (d) Noen of the above
Answer» Correct option (b) positive work is done on ice water system by the atmosphere Explanation: During melting of ice, volume decreases. ∴ Positive work is done on the system by the atmosphere

401.

During melting of an ice slab at 273 K at atmospheric pressure (a) positive work is done by ice water system on teh atmosphere (b) positive work is done on ice water system by the atmosphere (c) internal energy of ice water system decreases (d) Noen of the above

Answer»

Correct option (b) positive work is done on ice water system by the atmosphere

Explanation:

During melting of ice, volume decreases.

∴ Positive work is done on the system by the atmosphere

Discussion

402.	For the given velocity-time graph, velocity the corresponding displacement-time graph will be
Answer» Correct Option (d) Explanation : Here in velocity-time graph, the velocity is constant for first part, so displacement will increase at constant rate. In next part velocity is zero, so displacement will not increase or decreases. In last part, velocity is in negative direction so displacement will decreases and finally will become zero. Option (d) is correct In the first part the displacement will increase with time. In the intermediate part there is no change in velocity. So in this part of time the displacement remains unchanged i.e parallel to time axis. And in the last phase velocity reverses its direction. So the displacement will decrease with time .

402.

For the given velocity-time graph, velocity the corresponding displacement-time graph will be

Answer»

Correct Option (d)

Explanation :

Here in velocity-time graph, the velocity is constant for first part, so displacement will increase at constant rate.

In next part velocity is zero, so displacement will not increase or decreases.

In last part, velocity is in negative direction so displacement will decreases and finally will become zero.

Option (d) is correct

In the first part the displacement will increase with time. In the intermediate part there is no change in velocity. So in this part of time the displacement remains unchanged i.e parallel to time axis. And in the last phase velocity reverses its direction. So the displacement will decrease with time .

Discussion

403.	The ratio of CP and CV depends on temperature T according to relation :(a) y ∝ T(b) y ∝ T(c) y ∝ 1/T(d) y ∝ √T
Answer» Correct option (a) y ∝ T Explanation: The ratio of heat capacity pressure (C_p) to heat capacity at constant volume (C_V) is known as the heat capacity ratio or isentropic expansion factor C_p/C_v =y does not upon temperature.

403.

The ratio of CP and CV depends on temperature T according to relation :(a) y ∝ T(b) y ∝ T(c) y ∝ 1/T(d) y ∝ √T

Answer»

Correct option (a) y ∝ T

Explanation:

The ratio of heat capacity pressure (C_p) to heat capacity at constant volume (C_V) is known as the heat capacity ratio or isentropic expansion factor C_p/C_v =y does not upon temperature.

Discussion

404.	Which one of the following statements is not true of de-Broglie waves(a) All atomic particles in motion have waves of a definite wavelength associated with them(b) The higher the momentum, the larger is the wavelength(c) The fater the particle, the shorter is the wavelength(d) For the same velocity, a heavier particle has a shorter wavelength
Answer» Option (b) The higher the momentum, the larger is the wavelength Explanation : As,λ = h/p = h/mv where, h = Planck's constant, λ = wavelength, p = mv = momentum It is shown that wavelength λ is inversely proportional to the momentum. Hence, lighter the momentum, lesser will be the wavelength. So, statement (b) is not true. Option (b) is incorrect , Explanation By deBroglie equation we know , λ = h/p = h/mv where, h = Planck's constant, λ = wavelength, p = mv = momentum As the wave length λ is inversely proportional to momentum mv . So higher the momentum shorter is the wavelength.

404.

Which one of the following statements is not true of de-Broglie waves(a) All atomic particles in motion have waves of a definite wavelength associated with them(b) The higher the momentum, the larger is the wavelength(c) The fater the particle, the shorter is the wavelength(d) For the same velocity, a heavier particle has a shorter wavelength

Answer»

Option (b) The higher the momentum, the larger is the wavelength

Explanation :

As,λ = h/p = h/mv

where, h = Planck's constant, λ = wavelength, p = mv = momentum

It is shown that wavelength λ is inversely proportional to the momentum. Hence, lighter the momentum, lesser will be the wavelength. So, statement (b) is not true.

Option (b) is incorrect ,

Explanation

By deBroglie equation we know ,

λ = h/p = h/mv

where, h = Planck's constant, λ = wavelength,

p = mv = momentum

As the wave length λ is inversely proportional to momentum mv . So higher the momentum shorter is the wavelength.

Discussion

405.	How to give online NEET examination in Sarthak's?
Answer» Click here to practise:- Neet online Mock test 2022

405.

How to give online NEET examination in Sarthak's?

Answer»

Click here to practise:- Neet online Mock test 2022

Discussion

406.	In which of the following devices, the eddy current effect is not used? (1) Induction furnace (2) Magnetic braking in train (3) Electromagnet (4) Electric heater
Answer» The correct option is (4) Electric heater. Explanation: Eddy current techniques are commonly used for nondestructive examination and there are many devices which indeed use this Eddy Current Effect. For example, (1) Induction furnace (2) Magnetic braking in train; and the (3) Electromagnet However, the electric heaters do not use this effect in their nondestructive examination.

406.

In which of the following devices, the eddy current effect is not used? (1) Induction furnace (2) Magnetic braking in train (3) Electromagnet (4) Electric heater

Answer»

The correct option is (4) Electric heater.

Explanation:

Eddy current techniques are commonly used for nondestructive examination and there are many devices which indeed use this Eddy Current Effect.

For example,

(1) Induction furnace (2) Magnetic braking in train; and the (3) Electromagnet

However, the electric heaters do not use this effect in their nondestructive examination.

Discussion

407.	Nitric acid whether diluted or concentrated :(a) Reacts with Al to give H2(b) Reacts with Al to give NO2(c) Reacts with Al to give NH4 NO2(d) Hardly affects AI
Answer» Correct Option (d) Hardly affects AI Explanation : Al becomes passive in HNO₃

407.

Nitric acid whether diluted or concentrated :(a) Reacts with Al to give H2(b) Reacts with Al to give NO2(c) Reacts with Al to give NH4 NO2(d) Hardly affects AI

Answer»

Correct Option (d) Hardly affects AI

Explanation :

Al becomes passive in HNO₃

Discussion

408.	Which member of group 13 is liquid at 30°C ? (a) B (b) Al (c) Ga (d) T l
Answer» Correct Option (c) Ga Explanation : The m.p. are B(2300°C) AI(660° C) Ga(29.8° C)TI (303°C)

408.

Which member of group 13 is liquid at 30°C ? (a) B (b) Al (c) Ga (d) T l

Answer»

Correct Option (c) Ga

Explanation :

The m.p. are B(2300°C) AI(660° C) Ga(29.8° C)TI (303°C)

Discussion

409.	Alumina is . ..... .... . in nature.(a) Acidic (b) Basic(c) Amphoteric (d) Neutral
Answer» Correct Option (c) Amphoteric Explanation : It reacts with acids and alkalies both.

409.

Alumina is . ..... .... . in nature.(a) Acidic (b) Basic(c) Amphoteric (d) Neutral

Answer»

Correct Option (c) Amphoteric

Explanation :

It reacts with acids and alkalies both.

Discussion

410.	Intertribal hybrids were first obtained by which of the following scientist : (a) Gibbs and Hofmann (1966) (b) Gibbs and Hofmann (1982) (c) Gibbs and Hofmann (1976) (d) Gibss and Hofmann (1953)
Answer» Correct Option (c) Gibbs and Hofmann (1976)

410.

Intertribal hybrids were first obtained by which of the following scientist : (a) Gibbs and Hofmann (1966) (b) Gibbs and Hofmann (1982) (c) Gibbs and Hofmann (1976) (d) Gibss and Hofmann (1953)

Answer»

Correct Option (c) Gibbs and Hofmann (1976)

Discussion

411.	Match the following columns :Column-IColumn-IIA. Allogamy 1. Fusion of gametesB.Homogamy 2.Cross-pollinationC. Syngamy3. Male and female parts of a flower mature simultaneouslyABC(a)312(b)231(c)321(d)123
Answer» Correct Option (b)

411.

Match the following columns :Column-IColumn-IIA. Allogamy 1. Fusion of gametesB.Homogamy 2.Cross-pollinationC. Syngamy3. Male and female parts of a flower mature simultaneouslyABC(a)312(b)231(c)321(d)123

Answer»

Correct Option (b)

Discussion

412.	Match the following columnsABCD(a)2413(b)3214(c)4132(d)1234
Answer» Correct Option (a)

Discussion

413.	Study the following chain Sun ↓Given 1000 unit energy to phytoplanktons ↓Phytoplanktons are consumed by hebivorouszooplankton, and in turn received A unit of energy ↓carnivorous zooplanktons eat the herbivorous zooplanktonand get B unit of energy ↓Carnivorous fish takes carnivorous zooplanktons andreceived C unit of energy ↓In last, Tunas find their turn and engulf carnovore fishes to get D unit of energyIdentify A, B, C and DIfI. 0.1 unit II. 10 unitIII. 100 unit IV. 1 unitABCD(a)IIIIIIVI(b)IVIIIIII(c)IIIIIIIVI(d)Given information is not sufficient to answer
Answer» Correct Option (c)

413.

Study the following chain Sun ↓Given 1000 unit energy to phytoplanktons ↓Phytoplanktons are consumed by hebivorouszooplankton, and in turn received A unit of energy ↓carnivorous zooplanktons eat the herbivorous zooplanktonand get B unit of energy ↓Carnivorous fish takes carnivorous zooplanktons andreceived C unit of energy ↓In last, Tunas find their turn and engulf carnovore fishes to get D unit of energyIdentify A, B, C and DIfI. 0.1 unit II. 10 unitIII. 100 unit IV. 1 unitABCD(a)IIIIIIVI(b)IVIIIIII(c)IIIIIIIVI(d)Given information is not sufficient to answer

Answer»

Correct Option (c)

Discussion

414.	Match the following columns :Column IColumn IIA. Lymph1. Wharton's jellyB. Blood 2. Adipose cells C. Mucoid tissue3. Less glucose concentrationD. Reticular tissue4. Middle manABCD(a)1423(b)4213(c)4312(d)3124
Answer» Correct Option (c)

Discussion

415.	Choose the correct statement I. LSD – Ergot II. Mescalin – Peyote cactus III. Marijuana – Angel dust IV. Gnag – Cannabis sativa V. Opium – Synthetic drug (a) I, II and V (b) II, III and IV (c) I, II, and IV (d) None of the these
Answer» Correct Option (c) I, II, and IV

415.

Choose the correct statement I. LSD – Ergot II. Mescalin – Peyote cactus III. Marijuana – Angel dust IV. Gnag – Cannabis sativa V. Opium – Synthetic drug (a) I, II and V (b) II, III and IV (c) I, II, and IV (d) None of the these

Answer»

Correct Option (c) I, II, and IV

Discussion

416.	Identify the types of birth control device based on the features given below :I. Requires to erection of penisII. Can cause excess menstrual bleeding and painIII. Relatively unreliable and sometimes messy.(a) I–Diaphragm, II–certical cap, III–Implant(b) I–Levonorgestral, II–Hormonal pill, III–Norplant(c) I–Condom, II–IUD, III–Vaginal Suppositories(d) I–Certical cap, III–Oral contraceptive, III–Condom
Answer» Correct Option (c) I–Condom, II–IUD, III–Vaginal Suppositories

Discussion

417.	Which of the following gland do not secrete proteinaceous hormones : (a) Pancreas (b) Thyroid gland (c) Parathyroid gland (d) Ganads
Answer» Correct Option (d) Ganads

417.

Which of the following gland do not secrete proteinaceous hormones : (a) Pancreas (b) Thyroid gland (c) Parathyroid gland (d) Ganads

Answer»

Correct Option (d) Ganads

Discussion

418.	Which of the following statements is incorrect : (a) Ethidium bromide stained DNA can be seen in light (b) DNA cannot be seen in visible light (c) Ethidium bromide stained DNA can be seen when exposed to UV-light (d) DNA cannot be seen in visible light even if stained
Answer» Correct Option (a) Ethidium bromide stained DNA can be seen in light

Discussion

419.	Match the following columns :Column IColumn IIA. Biosynthesis of IAA 1. ZincB. Protein synthesis 2. ManganeseC. Hydrolysis of pyrophosphate3. Nitrogen D. Photolysis of water4. PhosphorusABCD(a)1423(b)4213(c)1342(d)3421
Answer» Correct Option (c)

Discussion

420.	In the given below fluid mosaic model of cell membrane, identify the markings,IfI. Hydrophobic tails II. CholesterolIII. Integral protein IV. Hydrophilic headsABCD(a)IVIIIIII(b)IIIIIIIV(c)IIIIIIVI(d)IVIIIIII
Answer» Correct Option (d)

420.

In the given below fluid mosaic model of cell membrane, identify the markings,IfI. Hydrophobic tails II. CholesterolIII. Integral protein IV. Hydrophilic headsABCD(a)IVIIIIII(b)IIIIIIIV(c)IIIIIIVI(d)IVIIIIII

Answer»

Correct Option (d)

Discussion

421.	The aleurone layer in maize grain is specially rich in which of the following molecules : (a) Starch (b) Proteins (c) Lipids (d) Cellulose
Answer» Correct Option (b) Proteins

421.

The aleurone layer in maize grain is specially rich in which of the following molecules : (a) Starch (b) Proteins (c) Lipids (d) Cellulose

Answer»

Correct Option (b) Proteins

Discussion

422.	A hormone is a class of regulatory biochemical produced in particular parts of organism by specific cells glands and/or tissues. Identify the systemic hormone from the following options :(a) Oxytocin (b) Somatostatin(c) Melatonin (d) Soatodrophin
Answer» Correct Option (d) Soatodrophin

Discussion

423.	An electric lamp having coil of negligible indicatanec connected in series with a capacitor and an ac source is glowing with certain brightness. If the capacitance is reduced then :–(a) Brightness will remain same(b) Brightness will increase(c) Brightness will decrease(d) Current will increase
Answer» Correct Option (c) Brightness will decrease Explanation: When capacitance C is reduced, X_c(= 1/ωc) increases. This reduces the current and hence brightness of the bulb.

423.

An electric lamp having coil of negligible indicatanec connected in series with a capacitor and an ac source is glowing with certain brightness. If the capacitance is reduced then :–(a) Brightness will remain same(b) Brightness will increase(c) Brightness will decrease(d) Current will increase

Answer»

Correct Option (c) Brightness will decrease

Explanation:

When capacitance C is reduced, X_c(= 1/ωc) increases. This reduces the current and hence brightness of the bulb.

Discussion

424.	One face of a glass cube of side 0.06 m is silvered. An object is placed at a distance of 0.07 m from the face opposite to the silvered face. Looking from the object side, the image of the object appears to be 0.11 m behind the silvered face. The refractive index of material of glass is :–(a) 1.5 (b) 1.3 (c) 0.4 (d) ∞
Answer» Correct Option (a) 1.5 Explanation: It is clear from figure that 0.07 + y = 0.11 y = 0.04 μ = 0.06/0.04 = 1.5

424.

One face of a glass cube of side 0.06 m is silvered. An object is placed at a distance of 0.07 m from the face opposite to the silvered face. Looking from the object side, the image of the object appears to be 0.11 m behind the silvered face. The refractive index of material of glass is :–(a) 1.5 (b) 1.3 (c) 0.4 (d) ∞

Answer»

Correct Option (a) 1.5

Explanation:

It is clear from figure that

0.07 + y = 0.11

y = 0.04

μ = 0.06/0.04 = 1.5

Discussion

425.	In a prism of angle A, the condition for no emergence of light is :–(a) μ>cosec(A/2)(b) μ> sin(A/2)(c) μ>cos(A/2)(d) μ>cos A(μ = refractive index of material of prism)
Answer» Correct Option (a) μ>cosec(A/2)

Discussion

426.	A step up transformer has turn ratio 10 : 1. A cell of emf 2 volts is fed to the primary. Secondary voltage developped is :–(a) 20 V (b) 10 V (c) 2 V (d) Zero
Answer» Correct Option (d) Zero Explanation: Transformer works only on ac input and here cell is providing dc input.

426.

A step up transformer has turn ratio 10 : 1. A cell of emf 2 volts is fed to the primary. Secondary voltage developped is :–(a) 20 V (b) 10 V (c) 2 V (d) Zero

Answer»

Correct Option (d) Zero

Explanation:

Transformer works only on ac input and here cell is providing dc input.

Discussion

427.	In Rutherford's atomic model, the impact parameter b is proportional to :–(a) cot θ/2(b) cos θ(c) V2(d) 1/Z
Answer» Correct Option (a) cot θ/2

Discussion

428.	The light of wavelength 600 nm is incident normally on a slit of width 3 mm. The linear width of central maximum on a screen kept 3 m away from the slit : –(a) 1.2 mm (b) 4.68 mm(c) 2.1 mm (d) 6.75 m
Answer» Correct Option (a) 1.2 mm Explanation: Linear width of central maxima = 2Dλ/a

428.

The light of wavelength 600 nm is incident normally on a slit of width 3 mm. The linear width of central maximum on a screen kept 3 m away from the slit : –(a) 1.2 mm (b) 4.68 mm(c) 2.1 mm (d) 6.75 m

Answer»

Correct Option (a) 1.2 mm

Explanation:

Linear width of central maxima = 2Dλ/a

Discussion

429.	A uniform chain of mass m and length l is lying on a table with l/4 of its length hanging freely from the edge of the table. The amount of work done in dragging the chain on the table completely is :–(a) mgl/4(b) mgl/8(c) mgl/32(d) mgl/16
Answer» Correct option (c) mgl/32 Explanation: Mass of (l/4) length of the chain = m/4 The weight of this part of the chain acts as its CG which is at a distance (L/8) from the edge of the table. Work done = (m/8) g (L/8) = mgl/32

429.

A uniform chain of mass m and length l is lying on a table with l/4 of its length hanging freely from the edge of the table. The amount of work done in dragging the chain on the table completely is :–(a) mgl/4(b) mgl/8(c) mgl/32(d) mgl/16

Answer»

Correct option (c) mgl/32

Explanation:

Mass of (l/4) length of the chain = m/4

The weight of this part of the chain acts as its CG which is at a distance (L/8) from the edge of the table.

Work done = (m/8) g (L/8) = mgl/32

Discussion

430.	Two metals A and B have work functions 2eV, 4eV respectively. Which metal has a lower threshold wavelength for photoelectric effect :–(a) B (b) A(c) Data insulfficient (d) Both A & B
Answer» Correct Option (a) B

Discussion

431.	A sodium lamp emits 3.14×1020 photons per second. The distance from the sodium lamp where flux of photon is one photon per second per cm2 :–(a) 5x109 cm (b) 5x108 cm(c) 0.5×109 cm (d) Zero
Answer» Correct Option (a) 5x10⁹ cm Explanation: Photon flux at a distance d = no. of photons emitted per second/4πd² = 3.14 x 10²⁰/4 x 3.14 x d² d = 5 x 10⁹ cm

431.

A sodium lamp emits 3.14×1020 photons per second. The distance from the sodium lamp where flux of photon is one photon per second per cm2 :–(a) 5x109 cm (b) 5x108 cm(c) 0.5×109 cm (d) Zero

Answer»

Correct Option (a) 5x10⁹ cm

Explanation:

Photon flux at a distance d = no. of photons emitted per second/4πd²

= 3.14 x 10²⁰/4 x 3.14 x d²

d = 5 x 10⁹ cm

Discussion

432.	At ordinary temperature, the molecules of an ideal gas have only translational and rotational kinetic energies. At high temperatures they may also have vibrational energy. As a result of this at higher temperatures (Cv = molar heat capacity at constant volume) :–(a) Cv = 3R/2 for a monoatomic gas(b) Cv > 3R/2 for a monoatomic gas(c) Cv > 5R/2 for a diatomic gas(d) Cv = 5R/2 for a diatomic gas
Answer» Correct option (c) C_v > 5R/2 for a diatomic gas Explanation: Monoatomic gas C_v = 3R/2 This value is same for high temperature also, In case of diatomic gas C_v = 5R/2 (at low temperature) Also,C_v > 5R/2 (at high temperature due to vibrational kinetic energy)

432.

At ordinary temperature, the molecules of an ideal gas have only translational and rotational kinetic energies. At high temperatures they may also have vibrational energy. As a result of this at higher temperatures (Cv = molar heat capacity at constant volume) :–(a) Cv = 3R/2 for a monoatomic gas(b) Cv > 3R/2 for a monoatomic gas(c) Cv > 5R/2 for a diatomic gas(d) Cv = 5R/2 for a diatomic gas

Answer»

Correct option (c) C_v > 5R/2 for a diatomic gas

Explanation:

Monoatomic gas C_v = 3R/2

This value is same for high temperature also, In case of diatomic gas

C_v = 5R/2 (at low temperature)

Also,C_v > 5R/2 (at high temperature due to vibrational kinetic energy)

Discussion

433.	DC current gain for common base amplifier is :–(a) (IC/IE)vCB(b) (ΔIC/ΔIE)vCB(c) (ΔIC/ΔIE)vCB(d) Zero
Answer» Correct Option (a) (I_C/I_E)v_CB

Discussion

434.	For the circuit shown here, the current flowing through the 1 Ω resistor is :– (Assume that the two doides D1, and D2 are ideal diodes)(a) 2A (b) 3A (c) 4A (d) zero
Answer» Correct Option (a) 2A Explanation: D₁ is forward biased. D₂ is reverse biased so, resistances D₁ and D₂ are zero and infinity respectively :. Total resistance = 2Ω Current, I = 6V/3Ω = 2A

434.

For the circuit shown here, the current flowing through the 1 Ω resistor is :– (Assume that the two doides D1, and D2 are ideal diodes)(a) 2A (b) 3A (c) 4A (d) zero

Answer»

Correct Option (a) 2A

Explanation:

D₁ is forward biased. D₂ is reverse biased so, resistances D₁ and D₂ are zero and infinity respectively

:. Total resistance = 2Ω

Current, I = 6V/3Ω = 2A

Discussion

435.	Options are A) N ( ch3)2 B) ohC) och3 D) c=N
Answer» Go for option D) c=N Auxochrome is the color enhancing group. C=N is not an example of auxochrome.

435.

Options are A) N ( ch3)2 B) ohC) och3 D) c=N

Answer»

Go for option D) c=N

Auxochrome is the color enhancing group. C=N is not an example of auxochrome.

Discussion

436.	Which of the following is carbocations is least stable
Answer» Correct Option (b) Explanation: Positive charge in on sp-hybridized carbon.

436.

Which of the following is carbocations is least stable

Answer»

Correct Option (b)

Explanation:

Positive charge in on sp-hybridized carbon.

Discussion

437.	The strongest acid among the following aromatic compounds is :–(a) p-nitrophenol (b) p-chlorophenol(c) p-cresol (d) m-nitrophenol
Answer» Correct option (a) p-nitrophenol Explanation: Electron withdrawing groups like —NO₂, —Cl stabilieses the phenoxide ion by dispersing negative charge, thus makes it more acidic. On the other hand electron releasing groups it more acidic. On the other hand electron releasing groups like —CH₃ destabilises the phenoxide ion and thus make it less acidic. —NO₂ is more withdrawing as compared to —Cl. That's why pnitrophenol is most acidic among the given.

437.

The strongest acid among the following aromatic compounds is :–(a) p-nitrophenol (b) p-chlorophenol(c) p-cresol (d) m-nitrophenol

Answer»

Correct option (a) p-nitrophenol

Explanation:

Electron withdrawing groups like —NO₂, —Cl stabilieses the phenoxide ion by dispersing negative charge, thus makes it more acidic. On the other hand electron releasing groups it more acidic. On the other hand electron releasing groups like —CH₃ destabilises the phenoxide ion and thus make it less acidic. —NO₂ is more withdrawing as compared to —Cl. That's why pnitrophenol is most acidic among the given.

Discussion

438.	Which is not applicable to N2O4 ?(a) It is diamagnetic at low temperature(b) It contains four nitrogen to oxygen bonds(c) It develops paramagnetism on heating to room temperature(d) It decolourises on heating to room temperature
Answer» Correct option (d) It decolourises on heating to room temperature Explanation: On heating, its colour depends due to its decomposition to NO₂.

438.

Which is not applicable to N2O4 ?(a) It is diamagnetic at low temperature(b) It contains four nitrogen to oxygen bonds(c) It develops paramagnetism on heating to room temperature(d) It decolourises on heating to room temperature

Answer»

Correct option (d) It decolourises on heating to room temperature

Explanation:

On heating, its colour depends due to its decomposition to NO₂.

Discussion

439.	Which of the following is not an electrophile ?(a) NH3 (b) BF3 (c) AlCl3 (d) SO3
Answer» Correct Option (a) NH₃ Explanation Nitrogen does not have any vacant orbital, rather it has lone pair of electrons.

439.

Which of the following is not an electrophile ?(a) NH3 (b) BF3 (c) AlCl3 (d) SO3

Answer»

Correct Option (a) NH₃

Explanation

Nitrogen does not have any vacant orbital, rather it has lone pair of electrons.

Discussion

440.	Modern synthetic theory of evolution involvesI. Gene mutationII. Changes in chromosome structure and numberIII. Genetic recombinationIV. Natural selectionThe correct terms are(a) I and II(b) III and IV(c) I, II and III(d) All of these
Answer» Answer is : (d) All of these Modern synthetic theory of evolution involves gene mutation, changes in chromosome structure and number, genetic recombination and natural selection. Gene mutations are changes in chromosome structure and number. Genetic recombination provides the genetic variability without which changes cannot take place. Natural selection guides populations of organisms for adaptation.

440.

Modern synthetic theory of evolution involvesI. Gene mutationII. Changes in chromosome structure and numberIII. Genetic recombinationIV. Natural selectionThe correct terms are(a) I and II(b) III and IV(c) I, II and III(d) All of these

Answer»

Answer is : (d) All of these

Modern synthetic theory of evolution involves gene mutation, changes in chromosome structure and number, genetic recombination and natural selection.

Gene mutations are changes in chromosome structure and number. Genetic recombination provides the genetic variability without which changes cannot take place.

Natural selection guides populations of organisms for adaptation.

Discussion

441.	Identify the incorrectly matched pair.(a) Eusporangiate—Selaginella(b) Leptosporangiate—Dryopteris(c) Both (a) and (b)(d) None of the above
Answer» Answer is : (d) Eusporangiate is the sporangium which is developed from a superficial group of cells, e.g. Selaginella. Leptosporangiate is the sporangium which is developed from a single superficial cell, e.g. Dryopteris.

441.

Identify the incorrectly matched pair.(a) Eusporangiate—Selaginella(b) Leptosporangiate—Dryopteris(c) Both (a) and (b)(d) None of the above

Answer»

Answer is : (d)

Eusporangiate is the sporangium which is developed from a superficial group of cells, e.g. Selaginella.

Leptosporangiate is the sporangium which is developed from a single superficial cell, e.g. Dryopteris.

Discussion

442.	Which of the following is a pair of alarm chemicals?(a) Opsonin and histones(b) Opsonin and dopamine(c) Interferons and dopamine(d) Histamine and kinins
Answer» Answer is : (d) Histamine and kinins Histamine and kinin are alarm chemicals which may cause inflammation at the spot of insect bite. Interferons are proteins secreted by virus-infected cells that inhibit neighbouring cells from making new viruses. Dopamine is a neurotransmitter. Opsonin are antibodies which make microbes more susceptible to phagocytosis.

442.

Which of the following is a pair of alarm chemicals?(a) Opsonin and histones(b) Opsonin and dopamine(c) Interferons and dopamine(d) Histamine and kinins

Answer»

Answer is : (d) Histamine and kinins

Histamine and kinin are alarm chemicals which may cause inflammation at the spot of insect bite.

Interferons are proteins secreted by virus-infected cells that inhibit neighbouring cells from making new viruses. Dopamine is a neurotransmitter. Opsonin are antibodies which make microbes more susceptible to phagocytosis.

Discussion

443.	The function of glycocalyx in bacteria is(a) protection from phagocytosis(b) prevention of desiccation(c) enable them to adhere to the surfaces(d) All of the above
Answer» Answer is : (d) The function of glycocalyx in bacteria is protection from phagocytosis and prevention of desiccation. It also enables them to adhere to the surfaces. Glycocalyx is made up of gelatinous, polysaccharide or polypeptide.

443.

The function of glycocalyx in bacteria is(a) protection from phagocytosis(b) prevention of desiccation(c) enable them to adhere to the surfaces(d) All of the above

Answer»

Answer is : (d)

The function of glycocalyx in bacteria is protection from phagocytosis and prevention of desiccation. It also enables them to adhere to the surfaces. Glycocalyx is made up of gelatinous, polysaccharide or polypeptide.

Discussion

444.	Consider the following statements.I. Habitat is the place or set of environmental conditions, in which a particular organism lives.II. Habitat can have number of niches.III. Niche have many species.IV. Niche is profession of an organism.The incorrect statement is(a) Only I(b) Only II(c) Only III(d) Only IV
Answer» Answer is : (c) Only III The statement III is incorrect. It is corrected as follows Niche have only one species. It is a functional description of the role, a species plays in a community.

444.

Consider the following statements.I. Habitat is the place or set of environmental conditions, in which a particular organism lives.II. Habitat can have number of niches.III. Niche have many species.IV. Niche is profession of an organism.The incorrect statement is(a) Only I(b) Only II(c) Only III(d) Only IV

Answer»

Answer is : (c) Only III

The statement III is incorrect. It is corrected as follows

Niche have only one species. It is a functional description of the role, a species plays in a community.

Discussion

445.	Arrange the steps in development of new varieties in correct order.I. Selection of the desirable characteristics.II. Creation of genetic variation.III. Evaluation of selected strains or lines or populations.IV. Multiplication of evaluated lines.Choose the correct option.(a) I → II → III → IV(b) I → III → II → IV(c) II → I → III → IV(d) III → IV → I → II
Answer» Answer is : (c) II → I → III → IV The development of new variety involves a series of inter - related and largely interdependent activities as in following steps First step is the creation of genetic variation. Second step involves selection of desirable characteristics. Third and fourth steps include evaluation of selected strains or lines or populations and multiplication of these evaluated lines.

445.

Arrange the steps in development of new varieties in correct order.I. Selection of the desirable characteristics.II. Creation of genetic variation.III. Evaluation of selected strains or lines or populations.IV. Multiplication of evaluated lines.Choose the correct option.(a) I → II → III → IV(b) I → III → II → IV(c) II → I → III → IV(d) III → IV → I → II

Answer»

Answer is : (c) II → I → III → IV

The development of new variety involves a series of inter - related and largely interdependent activities as in following steps

First step is the creation of genetic variation. Second step involves selection of desirable characteristics. Third and fourth steps include evaluation of selected strains or lines or populations and multiplication of these evaluated lines.

Discussion

446.	The sarcoplasmic reticulum of skeletal muscle is a(a) form of smooth endoplasmic reticulum(b) site where calcium is released during muscle relaxation(c) site of calcium binding protein storage(d) Both (a) and (c)
Answer» Answer is : (d) The sarcoplasmic reticulum is a modified smooth ER that serves alternatively a storage site for cellular calcium, which are necessary for muscle contraction.

446.

The sarcoplasmic reticulum of skeletal muscle is a(a) form of smooth endoplasmic reticulum(b) site where calcium is released during muscle relaxation(c) site of calcium binding protein storage(d) Both (a) and (c)

Answer»

Answer is : (d)

The sarcoplasmic reticulum is a modified smooth ER that serves alternatively a storage site for cellular calcium, which are necessary for muscle contraction.

Discussion

447.	Electronic smog refers to(a) invisible electromagnetic radiations(b) it causes harm to eyes(c) it affects brain cells of man(d) All of the above
Answer» Answer is : (d) Electronic smog refers to invisible electromagnetic radiations. It causes harm to eyes and also affects brain cells of man. These electromagnetic radiations are emitted from computers, televisions, etc.

447.

Electronic smog refers to(a) invisible electromagnetic radiations(b) it causes harm to eyes(c) it affects brain cells of man(d) All of the above

Answer»

Answer is : (d)

Electronic smog refers to invisible electromagnetic radiations. It causes harm to eyes and also affects brain cells of man. These electromagnetic radiations are emitted from computers, televisions, etc.

Discussion

448.	The ratio of inertial mass and gravitational mass is
Answer» Inertial Mass , m = F /a Gravitational mass , m' = W /g So , their ratio : m/m' = (F/a) / (W/g) = Fg/Wa

448.

The ratio of inertial mass and gravitational mass is

Answer»

Inertial Mass , m = F /a

Gravitational mass , m' = W /g

So , their ratio : m/m' = (F/a) / (W/g) = Fg/Wa

Discussion

449.	Photochemical smog always contains :–[a] O3 [b] CO [c] CH4 [d] PO4
Answer» Correct option [a] O₃

449.

Photochemical smog always contains :–[a] O3 [b] CO [c] CH4 [d] PO4

Answer»

Correct option [a] O₃

Discussion

450.	Which one of the following decides cell to divide :–(a) G1–phase (b) G2–phase(c) S–phase (d) None of these
Answer» Correct Option (a) G₁–phase

Discussion

Explore topic-wise InterviewSolutions in .

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Photochemical smog always contains :–[a] O3 [b] CO [c] CH4 [d] PO4

Which one of the following decides cell to divide :–(a) G1–phase (b) G2–phase(c) S–phase (d) None of these

In a prism of angle A, the condition for no emergence of light is :–(a) μ>cosec(A/2)(b) μ> sin(A/2)(c) μ>cos(A/2)(d) μ>cos A(μ = refractive index of material of prism)

Two metals A and B have work functions 2eV, 4eV respectively. Which metal has a lower threshold wavelength for photoelectric effect :–(a) B (b) A(c) Data insulfficient (d) Both A & B