Niche is
NEET 2018
For the following questions answer them individually
Which of the following is a secondary pollutant ?
In stratosphere, which of the following elements acts as a catalyst in degradation of ozone and release of molecular oxygen ?
World Ozone Dayis celebrated on
What type of ecological pyramid would be obtained with the following data?
Secondary consumer:120 g,
Primary consumer: 60 g
Primary producer: 10 g
Natality refers to
Offsets are produced by
The experimental proof for semiconservative replication of DNA was first shown in a
Select the correct match:
Which of the following has proved helpful in preserving pollen as fossils ?
Which of the following pairs is wrongly matched?
Which of the following flowers only once in a life-time ?
Select the Gorrect statement:
The Golgi complex participates in
The stage during which separation of the paired homologous chromosomes begins is
Stomata movement is not affected by
Stomata in grass leaf are
Which of the following is not a product of light reaction of photosynthesis ?
Which of the following is true for nucleous?
Which among the followis not a prokaryote?
The two functional groups characteristic of sugars are
Match the items given in Column I with those in Column II and select the correct option given below :
Which one is wrongly matched ?
After karyogamy followed by Meiosis, spores are produced exogenously in
Winged pollen grains are present in
Which of the following is commonly used as a vector for introducing a DNA fragment in human lympocytes?
A ‘new’variety of rice was patented by a foreign company, though such varieties have been present in India for a long time. This is related to
Use of bioresources by multinational companies and organisations without authorisation from the concerned country andits peopleis called
Select the correct match:
The correct order of steps in Polymerase Chain Reaction (PCR) is
In India,the organisation responsible for assesing the saftey of introducing genetically modified organisms for public use is
What is the role of $$NAD^{+}$$ in cellular respiration ?
Which one of the following plants shows a very close relationship with a species of moth, where none of the two can complete its life cycle without the other ?
Pollen grains can be stored for several years in liquid nitrogen having a temperature of
In which ofthe following formsis iron absorbed by plants ?
Double fertilization is
Oxygen is not produced during photosynthesis by
Which of the following elements is responsible for maintaining turgor in cells ?
Pneumatophores occur in
Select the wrong statement:
Secondary xylem and phloem in dicot stem are produced by
Sweet potato is a modified
Which of the following statements is correct?
Casparian strips occur in
Plants having little or no secondary growth are
Nissl bodies are mainly composed of
Which of these statements is incorrect ?
Many ribosomes may associate with a single mRNA to form multiple copies of a polypeptide simultaneously. Such strings of ribosomes are termed as
Which of the following terms describe human dentition ?
Which of the following events does not occur in rough endoplasmic reticulum ?
Select the incorrect match:
Which ofthe following is an amino acid derived hormone
Which of the following structures or regions is incorrectly paired with its function ?
Which of the following -hormones can play a significant role in osteoporosis ?
The transparentlens in the human eyeis held in ist place by
In a growing population of a country,
Match the items given in Column I with those in Column II and select the correct option given below?
Which part of poppy plant is used to obtain the drug “Smack” ?
Which one of the following population interactions is widely uséd immedical science for the production of antibiotics,?
All of the, following are included in ‘Ex-situ conservation’except
Which of the following gastric cells indirectly help in erythropoiesis ?
Match the items given in Column I with those in Column II and select the correct option given below :
Calcium is important in skeletal, muscle contraction becauseit
Which of the following is an occupational respiratory disorder?
AGGTATCGCATis a sequence from the coding strand of a gene. Whatwill be the corresponding sequence of the transcribed mRNA ?
A woman has an X-linked condition on one of her X chromosomes. This chromosome can be inherited by
Match the items given in Column I with those in Column II and select the correct option given below
According to Hugo de Vries, the mechanism of evolution is
All of the followingare part of an operon except
Which of the following options correctly represents the lung conditions in asthma and emphysema, respectively ?
Match the items given in Column I with those in Column II and select the correct option given below :
Match the items given in Column I with those in Column II and select the correct option given below :
Hormones secreted by the placenta to maintain pregnancy are
The contraceptive ‘SAHELI?
The difference between spermiogenesis and spermiation is
The amnion of mammalian embryo is derived from
Which of thefollowing animals does not undergo metamorphosis ?
Which one of these animals is mot a homeotherm ?
Which of the following features is used to identify a male cockroach from a female cockroach ?
Which of the following organisms are known as chief producers in the oceans ?
Ciliates differ from all otherprotozoans in
Identify the vertebrate group of animals characterized)by erop and gizzard in its digestive system.
Match the items given in Column I with those in Column II and select the correct option given below :
Match the items given in Column I with those in Column II and select the correct option given below :
Among the following sets of examples for divergent evolution, select the incorrect option:
Conversion of milk to curd improves its nutritional value by increasing the amount of
Which of the following characteristics represent ‘Inheritance of blood groups’ in humans?
a. Dominance
b. Co-dominance
c. Multiple allele
d. Incomplete dominance
e. Polygenic inheritance
Which of the following is not an autoimmune disease ?
The similarity of bone structuréjin the’ forelimbs of many vertebrates is anexample of
In which disease does mosquito transmitted pathogen .cause chronic inflammation of vessels
Acarbon resistor of $$(47 \pm 4.7) kΩ$$ is to be marked with rings of different colours for its identification. The colour code sequence will be
A set of ‘n’ equal resistors, of value ‘R’ each, are connected in series to a battery of emf ‘E’ and internal resistance ‘R’. The current drawn is I. Now,the ‘n’ resistors are connected in parallel to the same battery. Then the current drawn from battery becomes 10 I. The valueof‘n’ is
A battery consists of a variable number ‘n’ of identical cells (having internal resistance ‘r' each) which are connected in series. The terminals of the battery are short-circuited and the current I is measured. Which of the graphs shows the correct relationship between I and n?
The power radiated by a black body is P and it radiates maximum energy at wavelength,radiates maximum energy at wavelength,$$\lambda_{0}$$ If the temperature of the black body is now changed so that it radiates maximum energy at wavelength $$\frac{3}{4} \lambda_{0}$$, the power radiated by it becomes nP. The value of n is
Two wires are made of the same material and have the same volume. The first wire has cross-sectional area A and the second wire has cross-sectional area 3A. If the length ofthe first wire is increased by $$\delta $$ l on applying a force F, how much force is needed to stretch the second wire by the same amount ?
A sample of 0:1 g of water at $$100^\circ$$ C and normal pressure $$(1.013 \times 10^{5} N m^{-2})$$ requires 54 cal of heat energy to convert to steam at $$100^\circ$$.If the volume of the steam produced is 167.1 cc, the change in internal energy of thé ssample ,is
A small sphere.of radius ‘r’ falls from rest in a viscous liquid. As a result, heat is produced due to viscous force) The rate of production of heat when the sphere attains its terminal velocity, is proportional to
The momentof the force, $$\overrightarrow{F}=4\hat{i}+5\hat{j}-6\hat{k}$$ at (2, 0, — 3), about the point (2, — 2, — 2), is given by
A student measured the diameter of a small steel ball using a screw gauge of least count 0-001 cm. The main scale reading is 5 mm and zero of circular scale division coincides with 25 divisions above the reference level. If screw gauge has a zero error of — 0:004 cm,the correct diameter of the ball is
A toy car with charge q moves ona frictionless horizontal plane surface,under the influence of a uniform electric field $$\overrightarrow{E}$$ Due to the force q $$\overrightarrow{E}$$, its velocity increases from 0 to 6 $$\frac{m}{s}$$ in one second duration.At that instant the direction of the field is reversed . The car continues to move for two more seconds under the influence of this field .The average velocity and the average speed of the toy car between 0 to 3 séconds are respectively
A block of mass m is placed on a smooth inclined wedge ABC of inclination $$\theta$$ as shown in the figure. The wedge is given an acceleration ‘a towards the right. The relation between a and $$\theta$$ for the block to remain stationary on the wedge is
An em waveis propagating in a medium with a velocity $$\overrightarrow{V}=V\hat{i}$$ The instantaneous oscillating electric field of this em wave is along +y axis.Then the direction of oscillating magnetic field of the em wavewill be along
The refractive index of the material of a prism is $$\sqrt{2}$$ and the angle of the prism is $$30^\circ$$.one of the two refracting surfaces of the prism is made a mirror inwards, by silver coating. A beam of monochromatic light entering the prism from the other face will retrace its path (after reflection from the silvered surface)if its angle of incidence on the prism is
The magnetic potential energy stored.in a certain inductor is 25 mJ, when the current in the inductor is 60 mA. This inductoris:of inductance
An object is placed at a distance of 40 cm from a concave mirror of.focal length 15 cm.If the object is displaced through a distance of 20 cm towards the mirror, the displacementofthe image will be
The ratio of kinetic energy to the total energy of an electron in a Bohrorbit of the hydrogen atom, is
An electron of mass m with an initial velocity $$\overrightarrow{V}=V_{0} \hat{i} (V_{0}>0)$$ enters an electric field $$\overrightarrow{E}=-E_{0} \hat{i}$$ $$(E_{0}=constant >0)$$ at t=0. If $$\lambda_{0}$$ is its de-Broglie wavelength initially, then its de-Broglie wavelength at timet is
when the light of frequency 2 $$\nu_{0}$$ ( where $$\nu_{0}$$ is threshhold frequency), is incident on a metal plate ,the maximum velocity of electrons emitted is $$v_{1}$$.when the frequency of the incident radiation is increased to 5 $$\nu_{0}$$, the maximum velocity of electrons emitted from the same plate is $$V_{2}$$.The ratio of $$V_{1}$$ to $$V_{2}$$ is
For a radioactive material, half-life is 10 minutes. If initially there are 600 number of nuclei, the time taken (in minutes) for the disintegration of 450 nuclei is
The volume (V) of a monatomic gas varies with its temperature (T), as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state A to state B, is
The fundamental frequency in an open organ pipe is gers eeeea closed organ pipe.If the length of a closed organ pipe is 20 cm , then the length of closed organ pipe is
The efficiency of an ideal heat) engine working between the freezing point and boiling point of water,is
At what temperature will the rms speed of oxygen molecules become just sufficient for escaping from the; Earth’s atmosphere ?
(Given : Mass of oxygen molecule $$(m) = 2.76 \times 10^{-26} kg)$$
Boltzmann's constant $$k_{B}=1.38 \times 10^{-23} J K^{-1}$$
Unpolarised light is incident from air on a plane surface of a material of refractive index $$\mu$$. At a particular angle of incidence ‘i’, it is found that the reflected and refracted rays are perpendicular to each other. Which of the following options is correct for this situation ?
In Young’s double slit experiment the separation d between the slits is 2 mm, the wavelength $$\lambda$$ of the light used is 5896 A and distance D between the screen and slits is 100 cm.It is found that the angular width of the fringes is $$0-20^\circ$$ To increase the fringe angular width to $$0.21^\circ$$ (with same $$\lamda$$ and D) the seaparation between the slits needs to be changed to
An astronomical, refracting telescope will have large angular magnification and high angular resolution, when it has an objective lens of
In the circuit shown in the figure, the input voltage $$v_{i}$$ is 20 V , $$V_{BE}$$=0 and $$V_{CE}$$=0 The values of $$I_{B},I_{C},\beta$$ are given by
In a p-n junction diode, change in temperature dueto heating
In the combination of the following gates the output Y can be written in terms of inputs A and B as
A metallic rod of mass per unit length $$0.5 kg m^{-1}$$ is lying horizontally on a smooth inclined plane which makes an angle of $$30^\circ$$ with the horizontal. The rod is not allowed to slide down by flowing a current through it when a magnetic field of induction 0:25 T is acting on it in the vertical direction. The current flowing in the rod to keep it stationary is
An inductor 20 mH, a capacitor 100 $$\mu F$$ and a resistor 50 Q are connected in series across a source of emf, $$V = 10 \sin 314 t$$. The powerloss in the circuit is
A thin diamagnetic rod is placed vertically between the poles of an electromagnet. When,the current in the electromagnetis switched on, then the diamagnetic rod is pushed up, out,of the horizontal magnetic field. Hence, the rod gains gravitational potential energy. The work required to do this comes from
Current sensitive of a moving coil galvanomieter is 5 $$\frac{div}{mA}$$ and its voltage sensitivity (angular deflection per unit voltage applied ) is 20 $$\frac{div}{V}$$. The resistance of the galvanometer is
A tuning fork is used to produce resonance in a glass tube. The length of the air column in this tube can be adjusted by a variable piston. At room temperature of $$27^\circ$$C two successive resonances are produced at 20 cm and 73 cm of column length. If the frequency of the tuning fork is 320 Hz, the velocity of sound in air at $$27^\circ$$C is
The electrostatic force between the metal plates of an isolated parallel plate capacitor C having a charge Q and area A,is
A pendulum is hung from the roof of a sufficiently high building and is moving freely to and fro like a simple harmonic oscillatar. The acceleration of the bob of the pendulum is 20 $$\frac{m}{s^{2}}$$ at a distance of 5 m*fromithe mean position.The time period of oscillation
An electron falls from.rest through a vertical distance h in & uniform and vertically upward directed electric,field B. The direction of electric field is now reversed,keeping its magnitude the same. A protonisallowed to fall from rest in it through the'samejvertical distance h. The time of fall of the‘electron, in comparison to the time of fall of the proton is
The kinetic energies of a planet in an elliptical orbit about the Sun, at positions A,B and C are $$K_{A},K_{B}$$ and $$K_{C}$$, respectively AC is the major axis and SB is perpendicular to AC at the position of the Sun S as shown in the figure.Then
A solid sphere is in rolling motion. In rolling motion a body possesses translational kinetic energy $$(K_{t})$$ as well as rotational kinetic energy $$(K_{r})$$ simultaneously.The ratio $$K_{t}:(K_{t}+K_{r})$$ for the sphere is
If the mass of the Sun were tem times,smaller and the universal gravitational constant were ten times larger in magnitude , which of the following is not correct?
A solid sphereis) rotating freely about its symmetry axis in, free space. The radius of the sphere is imcreased keeping its mass same. Which of the following physical quantities would remain constant for the sphere ?
A body initially at rest and sliding along a frictionless track from a height h (as shown in Figure),just completes a vertical circle of diameter AB=D.The height h is equal to
Three objects, A : (a solid sphere), B : (a thin circular disk) and C : (a circular ring), each have the same mass M and radius R. Theyall spin with the same angular speed about their own symmetry axes. The amounts of work (W) required to bring them to rest, would satisfy the relation
Which one of the following statements is incorrect ?
A moving block having mass m, collides with another stationary block having mass 4m. The lighter blockycomesto rest after collision. When the initial velocity of the lighter block is v, then the value.of coefficient of restitution (e) will be
Iron carbonyl,$$Fe(CO)_{5}$$ is
Match the metal ions given in Column I with the spin magnetic moments of the ions given in Column II and assign the correct code :
Which of the following ions exhibits d-d transistion and paramagnetism as well?
The geometry and magnetic behaviour of the complex $$[Ni(CO)_{4}]$$ are
The type of isomerism shown by the complex $$[CoCl_{2}(en)_{2}]$$ is
Identify the major products P, Q and R in the following sequence of reactions :
Which of the,following compounds can form a zwitterion ?
For the redox reaction $${MnO_{4}}^{-}+{C_{2}O_{4}}^{2-}+H^{+} \rightarrow {Mn}^{2+}+CO_{2}+H_{2}O $$ the correct coefficients of the reactants for the balanced equation are
The correction factor ‘a’ to the ideal gas equation corresponds to
Which oneof the following conditions will favour maximum formation of the product in the reaction,
$$A_{2} (g)+B_{2} g \rightleftharpoons X_{2}(g) \triangle_{r}H=-XKJ$$
The bond dissociation energies of $$X_{2},Y_{2}$$ and XY are in the ratio of 1:0.5:1. $$\triangle H$$ for the formation of XY is — 200 kJ $$mol^{-1}$$ The bond dissociation of energy $$X_{2}$$ will be
When initial concentration of the reactant is doubled,. the half-life period of a zero order reaction
Which of the following molecules represents the order of hybridisation $$Sp_{2},Sp_{2},Sp,Sp $$from the left to right atoms?
Which of the following carbocations is expected to be most stable?
Which of the followingis correct with respect to — I effect of the substituents ? (R = alkyl)
The correct difference between first- and second-order reactions is that
Among $$CaH_{2},BeH_{2},BaH_{2},$$ the order of ionic charecter is
Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below:
Then the species undergoing disproportionation is
In which case is the number of molecules of water maximum ?
The compound A on treatment with Na gives B, and with $$PCl_{5}$$ gives C B and C react together to give diethyl ether. A, B and C are in the order
Hydrocarbon (A) reacts with bromine by substitution to form an alkyl bromide which by Wurtz reaction is converted to gaseous hydrocarbon containing less than four carbon atoms.(A)is
The compound $$C_{7} H_{8}$$ undergoes the following reactions :
The product 'C' is
Which oxide of nitrogen is not a common pollutant introduced into the atmosphere both due to natural and humanactivity ?
A mixture of 2:3 g formic acid and 4.5 g oxalic acid is aon with conic.$$H_{2}SO_{4}$$ The evolved mixture is passes through KOH pellets.Weight (in g) of the remaining product at STP will be
The difference between amylose and amylopectin is
Which of the following oxides is most acidic in nature ?
Nitration of aniline in strong acidic medium also gives m-nitroaniline because
Regarding cross-linked or network polymers,which of the following statements is incorrect ?
Following solutions were prepared by mixing different volumes of NaOH and HClof different Concentration
On which of the following properties does the coagulating powerofan ion depend ?
The solubility of $$BaSO_{4}$$ in water is $$2.42 \times 10^{-3} gL^{-1}$$ at 298K. The value of its solubility product $$(K_{sp})$$ will be
(Given molar mass of $$BaSO_{4} = 233 g mol^{-1}$$
Given van der)Waals constant for $$NH_{3}, H_{2},O_{2} and CO_{2}$$ respectively 4.17, 0.244, 1.36 and 3.59, which ‘one»of the following gases is most easily liquefied, ?
Magnesium reacts with an element (X) to form an ionic compound. If the ground state electronic configuration of (X) is $$1s^{2} 2s^{2} 2p^{3}$$, the simplest formula for this compoundis
Iron exhibits bee structure at room temperature. Above $$900^\circ$$C , it transforms to fcc structure. The ratio of density of iron at room temperature to that at $$900^\circ$$C (assuming molar mass and atemic radii of iron remains constant with temperature) is
Which one is a wrong statement?
Consider the following species
$${CN}^{+},{CN}^{-},NO and CN$$
Which one of these will have the highest bond order?
Which ofthe following statements is not true for halogens ?
Which one of the following elements is unable to form $${MF_{6}}^{3-}$$ ion ?
In the structure of $$ClF_{3}$$ the number of lone pairs of electrons on central atom ‘Cl’ is
Considering Ellingham diagram, which of the following metals can be used to reduce alumina ?
The correct order of atomicradi in group 13 elements is
The correct’ orner of N-compounds in its decreasing order of oxidation states is
In the reaction
the electrophile involved is
Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass.It is due to their
Compound A, $$C_{8}H_{10}O$$, is found to react with NaOI(produced by reacting Y with NaOH) and yields a yellow precipitate with charecteristic smell.
A and Y are respectively
