Explore topic-wise InterviewSolutions in .

Correct Option (d) All of the above

Answer is : (a)

Eukaryotic nuclei contain three distinct types of RNA polymerases that differ in RNA they synthesise.

The correct match is given by option (a).

Correct Option (c) Only I 

Answer is : (d)

KMnO₄ is used in analytical chemistry as it is used in quantitative analysis for detecting halides and oxalates. It is used as an oxidising agent in the laboratory as well as in industry. It is also used in bleaching of wool, cotton and silk.

Answer is : (c) Maintains the electrical neutrality of the two half-cells

Functions of salt-bridge Complete the cell circuit, maintains electrical neutrality in the solution of two half-cells, prevent diffusion of the solutions from one half-cell to the other.

Answer is : (c) Both (a) and (b) are correct

Bilirubin is produced in the macrophage-monocyte system by the breakdown of haemoglobin to biliverdin and then bilirubin. It is carried to the liver by attaching to the albumin as it is insoluble in water. In liver, bilirubin is conjugated with glucuronic acid by the enzyme glucuronyltransferase, making it soluble in water.

Answer is : (d) Cockroach

In cockroach, XX-XO sex chromosome complement is found. In this pattern, the female has two X-chromosomes (called XX) while male has only one X-chromosome (called XO). The X-chromosome is completely absent here. Thus, the presence of unpaired X-chromosome determines the masculine sex. The female produces only one type of eggs and male produces two types of sperms, i.e. 50% with one X-chromosome and 50% without any sex chromosome.

Answer is : (c) In the tissues, pCO₂ is high and it diffuses into blood and forms CO₂ and H₂O

The statement (c) is incorrect. CO₂ is trapped as bicarbonates at the tissue site and is transported to the alveoli where it is released out as CO₂. Carbon dioxide is immediately converted into H₂CO₃ after entering into the blood. This H₂CO₃ forms bicarbonates.

Answer is : (d) 

Chlamydospores are resistant spores formed under unfavourable conditions. Zoospores are formed in lower group of fungi of Phycomycetes. Aplanospores are non-motile structures. Conidia are exogenous spores.

Answer is : (b) Sewall Wright effect

Genetic drift is also called as Sewall Wright effect. Also known as allelic drift. Genetic drift is the change in the frequency of an existing gene variant (allele) in a population.

The evolutionary biologist Ernst Mayr proposed biological species concept. Hardy-Weinberg law is the fundamental law of population genetics. The attractions and loss of genetic variability has been termed as bottle neck effect.

Answer is : (d) Tetrasomy – 2n + 4 chromosomes

The option (d) is not correctly paired. In aneuploidy, an organism gains or loses one or more chromosomes but not a complete set. In tetrasomy (2n + 2), there is gain of 2 chromosomes. Aneuploid condition 2n - 1 is called monosomic. The aneuploid 2n + 1 is called trisomic.

(1) Grignard's reagent (RMgX) is a σ-bonded organometallic compound.

(3, 4) Those ionic compounds in which size of cation and anion is largely different show Frenkel defect. Non-stoichiometric ferrous oxide is Fe_0.93–0.96O_1.00 and it is due to metal deficiency defect.

(2) IBr₂^- ,XeF₂
Total number of valence electrons are equal in both the species and both the species exhibit linear shape.

The correct option is(4) O₃

Explanation:

Ozone (O₃) is a secondary pollutant as it is formed by the reaction amongst the primary pollutants. On the other hand, SO₂ is a primary pollutant. These pollutants persist in the environment in the form they are passed into it. CO is a qualitative pollutant. It is considered as pollutant only when its concentration reaches beyond a threshold value in the environment. CO₂ is a quantitative as well as a primary pollutant.

Correct Option (b) ML²/12

Explanation :

Moment of inertia of a uniform rod about one end = ml²/3

Momento of inertia of the system in which rod is bent

= 2x(M/2)(L/2)²/3 = ML²/12

Note : Here axis is perpendicular to the plane of the rod.

Correct Option (c) collision between the charged particles emitted

Explanation :

It is due to collision of charged particles emitted from the cathode and the atoms of the gas.

Correct option (a) magnetic pole   

Explanation:

At magentic pole, total intensity of earth's magnetic field is along the vertical.

∴ It has no horizontal component, Hence, the work done will be zero.

Answer is : (b) ∆Q_X > ∆Q_Y

∆U_X = ∆U_Y (For cyclic process)

So, ∆W_X = ∆Q_X and ∆W_Y > ∆Q_Y

As from figure, ∆W_X > ∆W_Y

So, ∆Q_X > ∆Q_Y

Answer : (b) Conjugation tube is not formed

The statement (b) is incorrect regarding Spirogyra. 

In it, conjugation tube is formed. 

The male gamete passes through this tube to unite with female gamete.

Correct Option(1) Bamboo species

Explanation:

Bamboo plants are perennial, monocarpic plants. They flower only once in their lifetime, usually after 50-100 years. They produce a large number of fruits and die. Mango, Jackfruit, and Papaya are polycarpic plants. i.e. they flower repeatedly at regular intervals every year.

Correct Option (a) Africa 

Correct Option (c) I, IV and II 

Correct Option  (c) Dystrophin gene 

Correct Option (b) If both assertion and reason are true and the reason is not the correct explanation of the assertion. 

Explanation :

According to Arrhenius equation, K = Ae^{-Ea /RT}

when EA = 0, K = A.

Answer is : (c) Brassicaceae

In plants of family – Brassicaceae, stamens are 6, arranged in two whorls, outer two stamens are short and inner four stamens are long (i.e. 2 + 4).

Correct Option (c) It is non-reactive 

Explanation :

CFC (chlorofluorocarbon) is non reactive and non-toxic hence used in air conditioner.

The correct option is(3) 16th September 

Explanation:

'World Ozone Day' is celebrated on 16th September to control O₃ depletion. Ozone layer is a fragile shield of gas that protects earth from harmful UV-rays.

On 21st Aprili the Civil Service Day and National Yellow Bat Day is ceiebrated. 5th June of every year is celebrated as World Environment Day.

Earth Day is an annual event, celebrated on 22nd April of every year.

Answer is : (d) 10 µC

In steady state, 

There will be no current in the capacitor branch. 

Net resistance of the first parallel branch and cell, 

R = 1+1+ 0.5 = 2.5Ω

Current drawn from the cell, 

i = \(\frac{V}{R}\) 

= \(\frac{2.5}{2.5}\) 

= 1A 

Potential drop across two parallel branches, 

V = E - ir

= 2.5 - 1\(\times\)0.5

= 2.5 - 0.5 

2 0 V 

So, charge on the capacitor plates 

q = CV 

= 5\(\times\)2 

= 10μC

Answer is : (b) 81%

Efficiency, η \(=\frac{81.2}{1+r_1/r_2}\%\)

So, η_max = 81.2 ≅ 81%

where, r₁ = forward bias diode resistance

and r₂ = load resistance.

For maximum efficiency, r₂ >> r₁

The correct option is (i) A/B.

Explanation:

Quantities having different dimensions can only be divided or multiplied but they cannot be added or subtracted.

Magnetic permeability is maximum for ferromagnetic substances.

Answer is : (b) 373 K

We know that at equilibrium, \(\triangle G=0\) for

given reaction

\(H_2O(l) \rightleftharpoons H_2O(v)\)

At equilibrium, \(\triangle G=0\)

\(\triangle G=\triangle H-T\triangle S=0\)

\(\triangle H=T\triangle S\)

\(T=\frac{\triangle H}{\triangle S}\)

\(=\frac{40.73\, kJ\, mol^{-1}} {0.109 \,kJ\, mol^{-1}}\)

= 373 K

Correct option is : (b) lowering the temperature and increasing the pressure

An exothermic reaction is a chemical reaction that releases energy in the form of light or heat.

The given reaction is an exothermic reaction, hence lowering the temperature and increasing pressure will favour forward reaction.

Answer is : (a) volatile stable compound

Ultra pure metals, are prepared by the van-Arkel method. Arkel method is used to purify oxide of titanium metal. Ti is heated with iodine to about 500 K to form volatile compound. The \(Til_4\) is reheated at 1700 K, when it decomposes to give pure Ti.

\(Ti+2l_2\overset{500 k}{\rightarrow} \underset{\text{Volatile stable compound}}{Til_4}\) \(\overset{1700 k}{\rightarrow} \underset{\text{Pure metal}}{Ti}+2l_2\)

The correct order of leaving group ability is : (b) IV > III > I > II

Leaving group ability depends upon basicity of group. The weaker the base, the greater is its leaving group ability. Alternatively, the stronger is conjugate acid, the greater the leaving group ability of the base.

The strength of conjugate acid is

HOSO₂CF₃ > HOSO₂Me > HOAc > HOMe.

Correct option (a) A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival

Correct option (a) Ribosome 

Correct option [a] vital index 

Correct option (c) Agaricus 

The correct option is(2) Limbic system :- consists of fibre tracts that interconnect different regions of brain; controls movement.

Explanation:

Limbic system consists of four major components namely hippocampus, amygdala, septal nuclei, and mammillary bodies. It controls the emotional behavior, food habits and sex behavior of an organism. It is not involved in controlling movements.

The rest three options are correctly paired with their functions.

The correct option is(3) Estrogen and Parathyroid hormone

Explanation:

Estrogen and parathyroid hormone can play a significant role in osteoporosis. It is caused due to the deficiency of estrogen and excessive activity of parathormones. Estrogen helps to promote the activity of osteoblast (helps in the formation of bone cells) and inhibits osteoclast (destruct the bones). On the other hand, parathormone promotes the mobilisation of calcium from bones into blood hence causes demineralisation.

The other listed hormones also contribute to osteoporosis but their effects are insignificant or very less. e.g.. low level of progesterone and aldosterone causes bone ]oss whereas raised level of prolactin has been linked with osteoporosis.