The frequency of an alternating voltage is 50 cycles/sec and its amplitude is 120V. Then the r.m.s. value of voltage is
The X - ray wavelength of L α line of platinum (Z - 78) is 1.30 Å . The X-ray wave length of L α line of molybdenum (Z = 42)
In a circuit two or more cells of the same e.m.f. are connected in parallel in order to
The equivalent capacitance between a and b for the combination of capacitors shown in figure where all capacitances are in microfarad is
A particle slides from rest from the top to down the outside smooth surface of a fixed sphere of radius r. It leaves the surface when the radius to the particle makes with the vertical an angle equal to—
Let the velocity be v when the body leaves the surface. From the freebody diagram,
When a wire is stretched and its radius becomes r/2, then its resistance will be
In strectching condition Resistance is inversely proportional to r4 since R is inversely proportional to A2 and area is directly proportional to r2(in sterching condition) so the ans should be A option which is 16 R
A step- up transformer is used on a 120 V line to provide a potential difference of 2400 V. If the primary coil has 75 turns, the number of turns in the secondary coil is
A solenoid of length 20 cm area of cross-section 4 cm2 and having 4000 turns is placed inside another solenoid of 2000 turns having a cross-section area 8 cm2 and length 10 cm. The mutual inductance of the system is
If ∈₀ and μ₀ represent the permittivity and permeability of vacuum and ∈ and μ represent the permittivity and permeability of medium, then refractive index of the medium is given by
Electric field and potential inside hollow charged conducting sphere are respectively where 'q' and 'r' are the charge and radius of given sphere.
An electric dipole has the magnitude of its charge as q, and its dipole moment is p. It is placed in a uniform electric field E. If its dipole moment is along the direction of the field, then force acting on it and its potential energy are respectively
If temperature of the sun were to increase from T to 2T and its radius from R to 2R, then how many times the radiant energy will be received on the earth?
From Stefan's law, the energy radiated by the sun is given by P=σeAT4,
Assuming e=1 for the sun.
In 1 st case, P1=σe × 4πR2 × T4
In 2nd case, P2 = σe × 4π(2R)2 × (2T)4
= σe × 4πR2 × T4 × 64 = 64P1
The rate at which energy received at the earth is,
where, AE = area of the earth,
RSE = distance between the sun and the earth.
When a satellite going round the eath in a circular orbit of radius r and speed V, loses some of its energy, then r and V change as
The total energy of a satellite in an orbit is giv... moreen by E=GMm/2R in magnitude. So when energy is lost R will decrease as it is obvious from the eqn. Moreover the kinetic energy of the satellite is given by K=GMm/2R. So when R decreases. the kinetic energy must increase and so does the velocity.The other way to look into the problem is that. when satellite is going round the planet. It's angular momentum i.e mvr must be constant about the centre of the orbit. so keep the same to a constant value. v must increase in order to compensate with the decrease in R.
A body of mass m is taken to the bottom of a deep mine. Then
Because acceleration due to gravity decreases
300 Joule of work is done in sliding a 2 kg. block on an inclined plane to a height of 10 meters. Taking value of acceleration due to gravity 'g' to be 10 m/s2, work done against friction is
Work done in lifting 2 kg mass upto height 10 metres is given by
W = mgh
= 2 x 10 x 10 = 200 J
Work done against friction
= 300 - 200 = 100 joule
In two separate setups of the Young's double slit experiment, fringe of equal width are observed when lights of wavelengths in the ratio 1:2 are used. If the ratio of the slit separation in two cases is 2:1, the ratio of distances, between the plane of slits and the screen, in the two setups is
Consider a 1 cc sample of air absolute temperature T₀ at sea level and another 1 cc sample of air at a height where the pressure is one-third atmosphere. The absolute temperature T of the sample at that height is
Cyclotron is used to accelerate
Cyclotron accelerates heavy positively charged particles which are used in nuclear experiments.
The centripetal force that is provided to the charged particle to move inside the cyclotron is due to varying electric field. The applied voltage around the Dee’s of cyclotron is too high, which forces the charged particles like alpha particle or protons etc. to be accelerated at very high speed.
An electrical meter of internal resistance 20 Ω gives a full scale deflection when one milliampere current flows through it. The maximum current, that can be measured by using three resistors of resistance 12 Ω each, in milliamperes is
Which of the following particles will describe the smallest circle when projected with the same velocity perpendicular to the magnetic field ?
The radius of the path taken by a charged particle in amagnetic field is given by
The mass by charge ratio is least for electron , thus it will have least radius.
Magnetic meridian is a
The magnetic meridian is an equivalent imaginary line connecting the magnetic south and north poles and can be taken as the horizontal component of magnetic force lines along the surface of the earth. Therefore, a compass needle will be parallel to the magnetic meridian.
If a bar magnet of moment μ is suspended in a uniform magnetic field B and it is given an angular deflection ' θ ' w.r.t its equilibrium position, the restoring torque on magnet is
Work done in turning a magnet of magnetic moment M by an angle of 90º from the magnetic meridian is n times the corresponding work done to turn through an angle of 60º, where n is
W1 = MB (cos 0º - cos 90º) = MB (1 - 0) = MB
W2 = MB (cos 0º - cos 60º) = MB (1 - 1/2 ) = MB/2
∴ W1 = 2W2
⇒ n = 2
A piece of steel floates in mercury. The specific gravities of mercury and steel are 13.6 and 7.8 respectively. For covering the whole piece, some water is poured over the mercury. What part of the steel piece will be inside the mercury?
Suppose volume of steel piece is V and
nV is volume of mercury.
nV x 13.6 + (V - nV ) x 1 = V x 7.8
n = 0.54
The moment of inertia of a body does not depend upon
According to the Hooke's law, if stress is increased, then ratio of stress to strain
Hence, if stress is increased, then the ratio of stress to strain remains constant.
A U-tube contains water and methylated spirit seperated by mercury. The mercury columns in the two arms are in level with 18 cm of water in one arm and 20 cm spirit in the other arm. The density of spirit is (Density of water=1 g-cm-3)
For water column in one arm of U - tube
h1 = 18 cm, ρ1 = 1 gm cm-3
For spint column in other arm of U - tube
h2 18 cm, ρ2 = ?
If P1 and P2 be the pressures exerted by water column and spirit column respectively
Then P1 = h1 ρ1 g
and P2 = h2 ρ2 g
The mercury columns in the two arms of U-tube are at the same level, thus in equilibrium
P1 = P2
or h1 ρ1 g = h2 ρ2 g
If an iron ball and a wooden ball of the same radius are released from a height 'h' in vaccum, then time taken by both of them to reach ground will be
Time taken by any body of mass m to reach the ground when dropped from a height h
From this equation time is independent of mass so t1 = t2
Since they are in vacuum there will be no air resistance, so time taken will be exactly equal.
α- particle is equivalent to
Positively charged particle emitted by various radioactive materials during decay. It consists of two neutrons and two protons, and is thus identical to the nucleus of a helium atom. The rest mass of the alpha particle amounts to 6.64424·10-27 kg, or 3.7273·109 eV.
A body of mass 4 kg weighs 4.8 kg when suspended in a moving lift. The acceleration of the lift is
As the apparent weight increase therefore we can say that acceleration of the lift is in upward direction.
The magnifying power of a telescope can be increased by increasing
A mass attached to a spring oscillates every 2 s. If the mass is increased by 2 kg, then time period increases by 1 s. The initial mass is
The overall process of carbon - Nitrogen fusion cycle results in fusion of four protons to yield the helium nucleus and two
When green light is incident on a certain metal surface electrons are emitted, but no electrons are emitted by yellow light. If red light is incident on the same metal surface then
Light of wavelength λ strikes a photo-sensitive surface and electrons are ejected with kinetic energy E. If the kinetic energy is to be increased to 2E, the wavelength must be changed to λ′ where
At the top of the trajectory of a projectile, the acceleration is
A satisfactory photographic print is obtained when the exposure time is 10 seconds at a distance of 2 m from a 60 Cd lamp. The time of exposure required for the same quality print at a distance of 4 m from a 120 Cd lamp is
Here D is constant and I
A convex lens is making full image of an object. If half of the lens is covered by an opaque object, then
When half the lens is covered, the amount of light passing through it will decrease resulting in decrease of intensity of the image. Exposed portion of the lens will form full image of the object.
Fraunhofer spectrum is a
Fraunhofer lines, in astronomical spectroscopy, any of the dark (absorption) lines in the spectrum of the Sun or other star, caused by selective absorption of the Sun's or star's radiation at specific wavelengths by the various elements existing as gases in its atmosphere.
A person cannot see clearly distances more than 40 cm. He advised to use lens of power
In which case application of angular velocity is useful
A body executes S.H.M. of period 3 s under the influence of one force, and S.H.M. of period 4 s under the influence of a second force. when both the forces act simultaneously in the same direction, the period of oscillation will be
The equation of motion of a particle excuting SHM is a + 16π2x = 0 . In this equation 'a' is linear acceleration in m/s2, of the particle at a displacement x in metres. The time period of SHM, in seconds is:
A semiconductor has an electron concentration of 8 x 1013 per m3 and the hole concentration of 5.5 x 1012per m3. The semiconductor is
A tuning fork produces certain sound waves in a medium. If temperature of the medium changes, which one of the following will change.
As velocity is directly proportional to temperature, and
frequency x wavelength =velocity,
Frequency is the property of source so that it remains constant, but wavelength will change.
p-n junction diode can be used as
In a capillary tube experiment, a vertical 30 cm long capillary tube is dipped in water. The water rises up to a height of 10 cm due to capillary action. If this experiment is conducted in a freely falling elevator, the length of the water column becomes
When a current is passed through water, acidified with a dilute sulphuric acid, the gases formed at the platinum electrodes are
In Seebeck series Sb appears before Bi. In a Sb-Bi thermocouple current flows from
For a given difference in temperature of two junctions of a thermocouple, the thermo e.m.f. is more if the separation between two metals in the Seebeck series used in the formation of thermocouple Sb and Bi are extreme metals of the series.
Which of the following is not equal to watt
A cylinder contained 10 kg of gas at 107 N/m2. The quantity of gas taken out of cylinder if final pressure is 2.5 x 106N ∕ m2 is (temp. is constant)
At constant temperature for the given volume of gas P1/P2 = m1/M2
The quantity of gas taken out of the cylinder = 10 – 2.5 = 7.5 kg.
At 100ºC, the substance that causes the most severe burn, is
A gas is compressed at a constant pressure of 50 N/m2 from a volume of 10 m3 to a volume of 4 m3. Energy of 100 J is then added to the gas by heating. Its internal energy is
Huygen's wave theory of light can not explain
Huygens wave theory of light cannot explain photoelectric effect phenomenon. It explains rectilinear propagation, reflection, refraction, interference, diffraction and polarization.
The unit of e.m.f. is
The force F on a sphere of radius 'a' moving in a medium with velocity 'v' is given by F=6πηav. The dimensions of η are
In interference pattern, the energy is
A man is watching two trains, one leaving and the other coming in with equal speeds of 4 m/sec. If they sound their whistles, each of frequency 240 Hz, the number of beats heard by the man (velocity of sound in air = 320 m/sec) will be equal to
Frequency of sound heard by the man from approaching train
Frequency of sound heard by the man from receding train
Hence, number of beats heard by man per sec = na − nr = 243 − 237 = 6
A car sounding a horn of frequency 1000 Hz passes an observer. The ratio of frequencies of the horn noted by the observer before and after passing of the car is 11:9. If the speed of sound is υ, the speed of the car is
A boy of mass 42 Kg eats bananas of 980 calories. If this energy is used up to lift him from the ground, the height to which he can move up is
Height = h.
Potential Energy (P.E) = 980 Calories = 4100.32 Jule
Now P.E = mgh
4100.32 = 42 x 9.8 x h
The enthalpies of formation for C₂H₄(g), CO₂(g) and H₂O(l) at 25ºC and 1 atm. pressure be 52, -395 and -286 kJ mol⁻1 respectively. The enthalpy of combustion of C₂H₄(g) will be
An example of a compound with the functional group - O - is
The reaction between primary amine, chloroform and alcoholic caustic potash is called
The carbylamine reaction (also known as the Hoffmann isocyanide synthesis) is the synthesis of an isocyanide by the reaction of a primary amine, chloroform, and base. The conversion involves the intermediacy of dichlorocarbene.
Which of the following composition of the petroleum corresponds to kerosene oil?
The homologue of ethyne is
C2H2 is Ethyne (homologue of alkyne)
C3H4 is propyne (homologue of alkyne)
C3H8 → propane (homologue of alkane)
C2H6 → Ethane (homologue of alkane)
1-Butyne reacts with cold alkaline KMnO₄ to yield
Which of the following salt would give SO₂ with hot and dil.H₂SO₄ and also decolourise Br₂ water?
Azimuthal quantum number of last electron of ₁₁Na is
Which of the following set of quantum numbers is correct for an electron in 4f-orbital?
Electrons will first enter into the orbital with the set of quantum numbers
We fill up electron in increasing energy order.in which electronic configuration n+l value is greater, it's energy also will be greater.but here n+l value is same.so we shall consider n(principle quantum number).in which electronic configuration n value is greater it's energy also will be greater.there for option C is correct.
A σ - bond is
The electronic configuration of metal M is 1s₂2s₂2p63s1. The formula of its oxide will be
In which of the following molecules, is the covalent bond most polar?
Difference of electronegativity between H and Cl is more
For an ideal gas the relationship between internal energy change .(∆E) and enthalpy change(∆H)is
The values of Kp1 and Kp2 for the reactions
are in the ratio of 9:1. If degree of dissociation of X and A be equal, then total pressure at equilibrium (1) and (2) are in the ratio:
X ⇌ Y + Z
1 0 0 initial mole
(1-α) α α mole at equilibrium
Which of these does not influence the rate of reaction?
The intensive property among these quantities is
An intensive property is a bulk property, meaning that it is a local physical property of a system that does not depend on the system size or the amount of material in the system. Examples of intensive properties include temperature, T; refractive index, n; density, ρ; and hardness of an object, η.
Tranquilisers are substances used for the treatment of
Tranquilizer, also spelled Tranquillizer, drug that is used to reduce anxiety, fear, tension, agitation, and related states of mental disturbance.
Which of the following IUPAC names is correct?
In which of the following solutions are ions present?
Which statement is incorrect?
Which of the following is isoelectronic with carbon atom?
Isoelectronic species: a group of ions, atoms, or molecules that have the same number of electrons. Thus, carbon and N+ are isoelectronic with 6 electrons.
Electronic configuration of C and N+:
When a metal is to be extracted from its ore and if the gangue associated with the ore is sillica, then
A real gas most closely approaches the behaviour of an ideal gas at
Which of the following statements is wrong for gases ?
The mass of gas can be determined by weighing the container, filled with gas and again weighing this container after removing the gas. The difference between the two weights gives the mass of the gas.
Which one of following properties of alkali metals increases in magnitude as the atomic number rises?
Element - Li Na K Rb Cs
76 102 138 152 167
as the atomic no. increases the no. of shells increases hence, atomic radius increases.
'Thermit' is a mixture of X parts of ferric oxide and Y parts of aluminium powder. X, Y respectively are
Which one of the following is a correct set for SiO₂?
Acidified solutions of sodium thiosulphate are unstable because in thiosulphate
The equivalent weight of phosphoric acid (H₃PO₄) in the reaction
NaOH+H₃PO₄ → NaH₂PO₄+H₂O is
Butter of tin is
Lithium and magnesium are similar in their properties due to the same
Lithium is an alkali metals whereas magnesium is an alkaline earth metal. Lithium is present in 1st group and magnesium is in 2nd group. The chemical properties of Li and Mg are similar due to diagonal relationship.
1.) The size of Li and Mg are similar.
2.) Li and Mg are harder and hence have high melting point irrespective of their group elements.
3.) Both show covalent nature.
4.) Carbonates of Li and Mg decomposes on heating to liberate CO2.
5.) Li and Mg can directly combine with N2.
6.) Both Li and Mg combine with carbon on heating.
7.) Both of these do not form alums.
The pink colour of phenolphthalein, in alkaline medium, is due to
Phenolphthalein (HIn) is weakly acidic in nature. And in aqueous solution, it dissociates into and ions. The pink colour of the solution is due to the concentration of ions in the solution. Under acidic conditions, the concentration of in the solution is very low and concentration of is high, hence it is colourless.
Ostwald's dilution law is applicable to
Ostwald’s dilution law is the application of the law of mass action to weak electrolytes in solution.
The reaction of KMnO₄ and HCl results in
The hydrides ion H⁻ is stronger base than its hydroxide ion OH⁻ .Which of the following reactions will occur if sodium hydrides (NaH) is disolved in water ?
The pH of a solution is increased from 3 to 6; its H⁺ ion concentration will be
pH= - log H+,
Using antilog, we will get H+ =10-3 for pH = 3 nd H+ = 10-6 for pH = 6.
So reduced by 1000 times..
Which of the following compounds can exhibit functional isomerism?
When chloroform reacts with acetone the product is
Chloroform combines with acetone in the presence of potassium hydroxide to give chloretone, which is used as a sleep producing (hypnotic) drug.
The reaction is represented as follows:
The projectile, which experiences minimum repulsion on approaching a particular nucleus, is
The order of decreasing ease of reaction with ammonia is
NH3 being nucleophile will attack acid anhydride and esters readily but will not attack another nucleophile (Lewis base) ether. Therefore order will be Anhydrides > Esters > Ethers
Of the following four reactions, formic acid and acetic acid differ in which respect?
Half-life of a redioactive substance which disintegrates by 75% in 60 minutes will be
Phenol, p-Methylphenol, m-Nitrophenol and p-Nitrophenol follows order of increasing acidic strength
Which of the following compounds can react with the Lewis base Cl− in a Lewis acid-base reaction?
When glycerol is treated with excess of HI, it produces
Glycerol is a trihydric alcohol whose IUPAC name is propane-1, 2, 3-triol and in industry it is known as glycerine.When glycerol is heated with excess of HI,the allyl iodide formed first is reduced to propene.Propene in presence of excess of HI forms iso-propyl iodide.
Conc. HNO3 forms NO2+ in presence of :
The structure of N-ethyl-N-methyl propan-1-amine is
Since, in this compound, the three valencies of nitrogen are satisfied by three different alkyl group, it is 3o amine.
SnCl₂ gives a precipitate with a solution of HgCl₂. In this process HgCl₂ is
Normality of 0.3 M H3PO4 solution is
Normality = molarity x basicity
Now, basicity of H3PO4 = 3
So, Normality = 0.3 x 3 = 0.9
The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because of
Colour of K2Cr2O7 changes from orange to lemon yellow on treatment with aqueous koh because of conversion of dichromate ion to chromate.
The edge length of the unit cell of body-centred lattice is 500 pm. If the radius of cation is 169 pm, then what is radius of anion?
Empirical formula of a compound is CH₂O. If its molecular weight is 180, then the molecular formula of the compound is
The empirical formula of the compound is CH2O, which has two numbers of atoms of hydrogen, and one atom of oxygen for each carbon. The mass of CH2O = 12+2 x 1+16 = 30. The approximate molecular weight of the compound is 180. So, the molecular formula of the given compound is C6H12O6.
Bakelite is prepared by the reaction between
Bakelite or polyoxybenzylmethylenglycolanhydride was the first plastic made from synthetic components. It is a thermosetting phenol formaldehyde resin, formed from a condensation reaction of phenol with formaldehyde.
Equivalent weight of which of the following metal can be determined by the hydrogen displacement method?
Which of the following can exhibit optical isomerism?
Equimolar solutions in the same solvent have
Boiling point and freezing point depend on Kb (molal elevation constant) and Kf(molal depression constant) of the solvent. Thus equimolar solution (of the non-electrolyte) will have same boiling point and also same freezing point.
ΔTf=Kf × molality
ΔTb=Kb × molality
Note: In question nature of solute has not been mentioned. Hence, we have assumed that solute is non-electrolyte.
Silver chloride dissolves in excess of NH4OH. The cation present in this solution is
Adsorbed acetic acid on activated charcoal is
A reagent that can separate Fe and Zn is
In coelenterates,the mouth of medusa is located on:
Medusa has a bowl or umbrella shaped body with marginal tentacles and mouth is centrally located in a projection called manubrium on the ventral concave surface. Medusae are generally motile and concerned with sexual reproduction.
Which factor promotes the appearance of the platelet plug?
Which of the following is the work of centrosome ?
Centrosomes are structures found inside of cells. They are made from two centrioles. Centrioles are microtubule rings. The main purpose of a centrosome is to organize microtubules and provide structure for the cell, as well as work to pull chromatids apart during cell division.
Which of these feeds upon dead organic matter with its maxillae picking up the food particles and bringing these to mandibles for mastication ?
How many molecules of oxygen are carried by one molecule of haemoglobin?
Hemoglobin, or Hb, is a protein molecule found in red blood cells (erythrocytes) made of four subunits: two alpha subunits and two beta subunits. Each subunit surrounds a central heme group that contains iron and binds one oxygen molecule, allowing each hemoglobin molecule to bind four oxygen molecules.
First heart transplant was performed by
On 3 December 1967, South African doctor, Dr Christiaan (Chris) Barnard, performed the world's first human to human heart transplant at Groote Schuur Hospital, Cape Town.
Coriandrum sativum is the botanical name of
Coriander (Coriandrum sativum), also known as cilantro, Chinese parsley or dhania, is an annual herb in the family Apiaceae. Coriander is native to regions spanning from southern Europe and North Africa to southwestern Asia.
The frenulum is the membrane attached to the inferior surface of the _____.
The inferior surface of the tongue is connected to the floor of the mouth by a median fold of mucous membrane, the frenulum. The submandibular duct opens on an elevation, the sublingual papilla, on the sides of the frenulum.
Which of the following is true of the liver?
Botanical name of cauliflower is
The plants face wilting due to the use of excessive fertilizers, because of
By using of excessive fertilizers, outer solutions of plants get hypertonic,then water in plants comes out to mentain osmolarity, so plants face wilting.
Agriculture was originated in mesolithic age about
Which one has maximum biomass?
Biomass refers to the amount of living organic matter. Forest ecosystem have the maximum biomass, because it includes organisms of all tropic levels as compared to pond, lake or grassland ecosystem. In forest ecosystems productivity is also high that contributes to maximum biomass.
Moderate rainfall during summer produces
A plant introduced from new world to old world is
Christopher Columbus introduced horses, sugar plants, and disease to the New World, while facilitating the introduction of New World commodities like sugar, tobacco, chocolate, and potatoes to the Old World. The process by which commodities, people, and diseases crossed the Atlantic is known as the Columbian Exchange.
'Sella turcica' is a depression in
Which of the following is a duel purpose breed?
Deoni is a dual purpose breed, usually females are good milk yielders and the males serve in ploughing.
Which one has always a steeper vertical gradient?
Father of genetics is
Father of Genetics. Gregor Mendel, through his work on pea plants, discovered the fundamental laws of inheritance. He deduced that genes come in pairs and are inherited as distinct units, one from each parent.
Which are identical?
Telomere of eukaryotic chromosome possesses short segments of
Sickle-cell anaemia is an example of :
Which of the following plant produces seeds but not flowers ?
Pinus belong to order coniferales of Gymnosperms. The plant is differentiated into root, stem and leaves. Plants are monoecious. Both male and female cones are borne on the same plant. It develops clusters of shortly stalked male cones subterminally on the lower branches and female cones in circle of 2 - 6 on upper long branches. A male cone has a central axis and a number of spirally arranged microsporophylls. A microsporophyll bears two oblong microsporangia abaxially on the proximal part. The terminal flattened part is bent and sterile. A microsporangium produces a large number of yellow pollen grains. Each pollen grain has two wings or air sacs for floating in the air. The central axis of female cone bears paired scales. In each pair the lower scale is bract scale while the upper one is ovuliferous scale (= megasporophyll complex), the terminal sterile part of ovuliferous scale is broad and called apophysis. The proximal adaxial side bears two ovules.
The wood of pinus is
The wood of Pinus is pycnoxylic (more than one ring due to epimeral nature of cambium) and monoxylic (formed by the activity of single cambium).
What is common in Whale, Bat and Rat?
Whale, bat and rat are mammals. Diaphragm is present in mammals. The diaphragm separates the thoracic cavity (with lung and heart) from the abdominal cavity (with digestive system and urogenital system). In its relaxed state, the diaphragm is shaped like a dome. It is controlled by the phrenic nerve.
Tay-Sachs disease is associated with
Sequence of eye covering (outer to inner) is
Sclera: The tough outer coat that protects the entire eyeball.
Choroid: Layer of the eye behind the retina, contains blood vessels that nourish the retina.
Retina: The light sensitive layer of tissue that lines the back of the eye.
In India, human population is heavily weighed towards the younger age groups as a result of
A population having mostly younger age group means its birth rate is high. If death rate is increased then the proportion of old age group will be increased. But in this case death rate has increasing trend thence in a human population which is heavily weighted towards the younger age groups; there will be short life span and high birth rate.
Which of the following contain lymph fluid?
Proprioceptors are sensory receptors that relay information to the brain about our body's position. The brain analyzes the information providing an awareness of where the body is in space. Proprioception and the proprioceptors that facilitate proprioception allow us to do things without seeing everything we do.
Closed circulatory system does not occur in:
Which of these would not be found in lymph fluid?
Exanthema is result of deficiency of
A plant is kept in 300 ppm CO₂ concentration.What will happen to it
Antimalaria drug is got from
Vestigial pelvic girdle and bones of hind limbs are characteristic of:
Whales have a vestigial pelvic girdle and reduced bones of hind limbs.
Physiologically active form of phytochrome is
Nicotinamide adenine dinucleotide is a cofactor that is central to metabolism. Found in all living cells, NAD is called a dinucleotide because it consists of two nucleotides joined through their phosphate groups. One nucleotide contains an adenine nucleobase and the other nicotinamide.
Oswald Tippo's classification is based on
In 1942, Oswald Tippo proposed a modern classification of the plant kingdom. He divided entire plant Kingdom into two major groups, Thallophyta and Embryophyta on the basis of absence and presence of an embryo.
In which one of the following pathogens do the cells of promycelium after the germination of teleutospore produce infection hyphae instead of basidiospores?
Auxin suppresses growth of
Nitrogen fixation occurs in
Glass Rope sponge is
The Glass Rope Sponge is a very unique species of sponges. For instance, these sponges have no organ system or tissues, can grow to be 6ft tall, and its skeleton is completely made up of silica, giving this species their glass-like appearance.
In rabbit, man and other placental mammals the organ in which fertilization of ovum occurs, is
Ozone layer of stratosphere requires protection from indiscriminate use of
Aerosols and high flying jets release nitric oxide into the upper atmosphere which leads to the distinction of ozone layer.
A pollen grain is best defined as
Spraying of DDT on crops causes pollution of