datavorous/entrance-exam-dataset huggingface dataset:
Which one of the following is correct structure for cytosine ?

Options:
A
B
C
D

The correct answer is:

Solution:
The correct structure of cytosine

Topic: Chemistry, Biomolecules, JEE Main, JEE Main 2021 (25 Jul Shift 2)
Which one of the following is correct? The eccentricity of the conic
$$
\frac{x^{2}}{a^{2}+\lambda}+\frac{y^{2}}{b^{2}+\lambda}=1,(\lambda \geq 0)
$$

Options:
A increases with increase in $\lambda$
B decreases with increase in $\lambda$
C does not change with $\lambda$
D None of the above

The correct answer is:
decreases with increase in $\lambda$

Solution:
Equation of the given conic is an equation of ellipse
$\frac{x^{2}}{a^{2}+\lambda}+\frac{y^{2}}{b^{2}+\lambda}(x \geq 0)$
$\Rightarrow \quad A^{2}=a^{2}+\lambda$ and $B^{2}=b^{2}+\lambda$
Eccentricity, $\mathrm{e}=\sqrt{1-\frac{\mathrm{B}^{2}}{\mathrm{~A}^{2}}}=\sqrt{1-\frac{\mathrm{b}^{2}+\lambda}{\mathrm{a}^{2}+\lambda}}$
$=\sqrt{\frac{a^{2}+\lambda-b^{2}-\lambda}{a^{2}+\lambda}}=\sqrt{\frac{a^{2}-b^{2}}{a^{2}+\lambda}}$
$\lambda$ is in the denominator so, when $\lambda$ increases, the eccentricity decreases.

Topic: Mathematics, Ellipse, JEE Main
Which one of the following is essential for photolysis of water?

Options:
A Manganese
B Zinc
C Copper
D Boron

The correct answer is:
Manganese

Solution:
Photolysis of water requires light energy, and oxygen evolving complex (OEC) and an electron carrier $Y_z$. OEC complex was formerly called Z-enzyme. It has four Mn ions. Light energy brings about changes in $\mathrm{Mn}\left(\mathrm{Mn}^{+2}, \mathrm{Mn}^{+3}, \mathrm{Mn}^{+4}\right)$ which helps in removing electrons from $\mathrm{OH}^{-}$ component of water forming oxygen. Liberation of oxygen also requires $\mathrm{Cl}^{-}$and $\mathrm{Ca}^{2+}$.

Topic: Biology, Mineral Nutrition, NEET, NEET 2011 (Mains)
Which one of the following is expected to exhibit optical isomerism (en = ethylenediamine)

Options:
A cis $-\left[\mathrm{Pt}\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]$
B trans - $\left[\mathrm{Co}(e n)_2 \mathrm{Cl}_2\right]$
C trans $\left[\mathrm{Pt}\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]$
D cis - $\left[\mathrm{Co}(\mathrm{en})_2 \mathrm{Cl}_2\right]$

The correct answer is:
cis $-\left[\mathrm{Pt}\left(\mathrm{NH}_3\right)_2 \mathrm{Cl}_2\right]$

Solution:
$\left[\mathrm{Co}\left(\mathrm{NH}_3\right)_4 \mathrm{Cl}_2\right]^{+}$is the $\mathrm{Ma}_4 b_2$ and $\mathrm{Ma}_2 b_3$ type complex.

Topic: Chemistry, Coordination Compounds, JEE Main
Which one of the following is formed (mainly) when red phosphorus is heated in a sealed tube at 803 K?

Options:
A α-Black phosphorus
B White phosphorus
C Yellow phosphorus
D β-Black phosphorus

The correct answer is:
α-Black phosphorus

Solution:
When red phosphorous is heated in a sealed tube at 803 K, then α-black phosphorous is formed.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), JEE Main, JEE Main 2021 (27 Aug Shift 2)
Which one of the following is heterosporous?

Options:
A Equisetum
B Dryopteris
C Salvinia
D Adiantum

The correct answer is:
Salvinia

Solution:
Others are homosporous pteridophytes.

Topic: Biology, Plant Kingdom, NEET, NEET 2008 (Mains)
Which one of the following is incorrect about the characteristics of protobionts (coacervates and micropheres) as envisaged in the abiogenic origin of life?

Options:
A They could maintain an internal environment
B They were able to reproduce
C They could separate combinations of molecules from the surroundings
D They were partially isolated from the surroundings

The correct answer is:
They were able to reproduce

Solution:
According to recent literature, coacervates and microsphere do not reproduce.

Topic: Biology, Evolution, NEET, NEET 2008 (Mains)
Which one of the following is incorrect about the characteristics of protobionts (coacervates and microspheres) as envisaged in the abiogenic origin of life?

Options:
A They were able to reproduce
B They could separate combinations of molecules from the surroundings
C They were partially isolated from the surroundings
D They could maintain an internal environment

The correct answer is:
They could maintain an internal environment

Solution:
- The kangaroo-rat is adapted to live in hot and dry conditions of the desert
- They can survive without drinking any water and get the needed moisture from their seed diet.
- They conserve water by lowering their metabolic activity which reduces loss of water through their skin and respiratory system.

Topic: Biology, Evolution, NEET, NEET 2008 (Screening)
Which one of the following is incorrect regarding compound epithelium?

Options:
A Multi-layered with no stretchability.
B Cover the moist surface of buccal cavity and pharynx.
C Provide protection against chemical and mechanical stress.
D Thy play a vital role in secretion and absorption.

The correct answer is:
Thy play a vital role in secretion and absorption.

Solution:
The compound epithelium is made of more than one layer (multi-layered) of cells and thus has a limited role in secretion and absorption. Their main function is to provide protection against chemical and mechanical stresses. They cover the dry surface of the skin, the moist surface of the buccal cavity, pharynx, the inner lining of ducts of salivary glands and of pancreatic ducts.

Topic: Biology, Structural Organisation in Animals, NEET
Which one of the following is known as broad spectrum antibiotics?

Options:
A Streptomycine
B Amylopectin
C Chloramphenicol
D Penicillin G

The correct answer is:
Chloramphenicol

Solution:
Chloramphenicol is a broad spectrum antibiotic used in the treatment of typhoid, dysentry, acute fever etc. Another example would be Ampicillin.

Topic: Chemistry, Chemistry in Everyday Life, JEE Main
Which one of the following is laevorotatory

Options:
A Glucose
B Sucrose
C Fructose
D None of these

The correct answer is:
Fructose

Solution:
Fructose is leayorotatary

Topic: Chemistry, Biomolecules, JEE Main
Which one of the following is likely to give a precipitate with AgNO3 solution?

Options:
A CH2=CH-Cl
B CH33CCl
C CCl4
D CHCl3

The correct answer is:
CH33CCl

Solution:
Reason: Due to most stable carbocatin formation tert-butyl chloride given the ppt immediately.

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2019 (12 Apr Shift 2)
Which one of the following is linked to the discovery of Bordeaux mixture as a popular fungicide?

Options:
A Black rust of wheat
B Bacterial leaf blight of rice
C Downy mildew of grapes
D Loose smut of wheat

The correct answer is:
Downy mildew of grapes

Solution:
It was discovered by Professor Millardet of Bordeaux University of France.

Topic: Biology, Strategies for Enhancement in Food Production, NEET, NEET 2008 (Mains)
Which one of the following is mainly responsible for depletion of ozone layer?

Options:
A Methane
B Cabon dioxide
C Water
D Chloro-fluoro carbons

The correct answer is:
Chloro-fluoro carbons

Solution:
Chloro-fluoro carbons

Topic: Chemistry, Environmental Chemistry, AP EAMCET, AP EAMCET 2001
Which one of the following is mainly responsible for depletion of ozone layer?

Options:
A Methane
B Carbon dioxide
C Water
D Chlorofluorocarbons

The correct answer is:
Chlorofluorocarbons

Solution:
Chlorofluorocarbons are responsible for the depletion of ozone layer as they provide Cl free radical which infact reacts with ozone and converts it into $\mathrm{O}_2$ as
$\mathrm{Cl}^{\bullet}+\mathrm{O}_3 \longrightarrow \mathrm{ClO}^{\bullet}+\mathrm{O}_2$

Topic: Chemistry, Environmental Chemistry, JIPMER, JIPMER 2012
Which one of the following is mainly responsible for depletion of ozone layer?

Options:
A Methane
B Cabon dioxide
C Water
D Chloro-fluoro carbons

The correct answer is:
Chloro-fluoro carbons

Solution:
Chloro-fluoro carbons

Topic: Chemistry, Environmental Chemistry, TS EAMCET, TS EAMCET 2001
Which one of the following is monoecious?

Options:
A Marchantia
B Cycas
C Pinus
D Date palm

The correct answer is:
Pinus

Solution:
Pinus is a monoecious gymnospermic plant, ie, both male and female cones occur on the same plant.
Marchantia (bryophyte), Cycas (gymnosperm) and date palm (angiosperm) all are dioecious plants, ie, male and female plants are separate.

Topic: Biology, Plant Kingdom, NEET, NEET 2010 (Mains)
which one of the following is most acidic?

Options:
A
B
C
D

The correct answer is:

Solution:
−I group increase the acidic strength of phenol.

Topic: Chemistry, d and f Block Elements, JEE Main
Which one of the following is most appropriately defined?

Options:
A Host is an organism, which provides food to another organism
B Amensalism is a relationship in which one species is benefited whereas the other is unaffected
C Predator is an organism that catches and kills other organism for food
D Parasite is an organism, which always lives inside the body of other organism and may kill it

The correct answer is:
Predator is an organism that catches and kills other organism for food

Solution:
Predator is an organism which catches and kills another organism (prey) for obtaining food. The term host' is also used for an organism which provides food to another organism but it is not a general term. Since, it is specific to parasitic interrelationship only.

Topic: Biology, Organisms and Populations, NEET, NEET 2010 (Mains)
Which one of the following is most likely a mismatch?

Options:
A

Zinc-Liquation

B

Copper-Electrolysis

C

Nickel-Mond process

D

Titanium-van Arkel Method

The correct answer is:

Zinc-Liquation

Solution:
Mond's process involves the combination of carbon monoxide with nickel readily and reversibly and gives nickel tetracarbonyl. This process is used to extract and purify nickel.

The Van Arkel technique is used to refine Zirconium or Titanium. Impurities found in Zirconium or Titanium in the form of nitrogen and oxygen are eliminated using this technique.

Copper is purified by electrolysis. Electricity is passed through solutions containing copper compounds, such as copper sulphate. The anode (positive electrode ) is made from impure copper and the cathode (negative electrode) is made from pure copper.

Mercury and zinc are purified by distillation method. Liquation is a metallurgical method to remove lead containing silver from copper and remove antimony minerals from ore.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, JEE Main, JEE Main 2023 (13 Apr Shift 1)
Which one of the following is most soluble

Options:
A $\operatorname{CuS}\left(K_{s p}=8 \times 10^{-37}\right)$
B $\operatorname{MnS}\left(K_{s p}=7 \times 10^{-16}\right)$
C $B i_2 S_3\left(K_{s p}=1 \times 10^{-70}\right)$
D $A g_2 S\left(K_{s p}=6 \times 10^{-51}\right.$

The correct answer is:
$\operatorname{MnS}\left(K_{s p}=7 \times 10^{-16}\right)$

Solution:
Solubility is directly proportional to the $K_{s p}$.

Topic: Chemistry, Ionic Equilibrium, JEE Main
Which one of the following is most stable ?

Options:
A

B

C

D

The correct answer is:

Solution:
$3^{\circ}$ carbocations are most stable.

Topic: Chemistry, General Organic Chemistry, JEE Main, JEE Main 2013 (09 Apr Online)
Which one of the following is not a broad spectrum antibiotic?

Options:
A Tetracycline
B Chloromycetin
C Penicillin
D None of these

The correct answer is:
Penicillin

Solution:
Penicillinis not a broad spectrum antibiotic since it is active against infections caused by gram positive bacteria only.

Topic: Chemistry, Chemistry in Everyday Life, JEE Main
Which one of the following is not a characteristic of phylum Annelida?

Options:
A Ventral nerve cord
B Closed circulatory system
C Segmentation
D Pseudocoelom

The correct answer is:
Pseudocoelom

Solution:
No Solution Available

Topic: Biology, Animal Kingdom, NEET, NEET 2008 (Mains)
Which one of the following is not a common component of Photochemical Smog?

Options:
A Ozone
B Acrolein
C Peroxyacetyl nitrate
D Chloroflurocarbons

The correct answer is:
Chloroflurocarbons

Solution:
Photochemical smog is a mixture of air pollutants which have been chemically altered into further noxious compounds by exposure to sunlight. The main components of photochemical smog are nitrogen oxides, Volatile Organic Compounds (VOCs), tropospheric ozone, and PAN (peroxyacetyl nitrate).

Chlorofluorocarbons are responsible for ozone layer depletion. Chlorofluorocarbon is not a component of the smog as it takes part in the depletion of the ozone layer. This depletion can result in climate changes but it is not part of the smog.

Topic: Chemistry, Environmental Chemistry, NEET, NEET 2014
Which one of the following is not a common component of photo-chemical smog?

Options:
A Ozone
B Acrolein
C Peroxy acetyl nitrate
D Chloroflourocarbons

The correct answer is:
Chloroflourocarbons

Solution:
Photo-chemical smog is a mixture of air pollutants which have been chemically altered into further poisonous
compounds on exposure to sunlight
The main components of photochemical smog are nitrogen oxides, volatile organic compounds, tropospheric ozone and
peroxyacetyl nitrate (PAN)

Topic: Chemistry, Chemical Kinetics, KCET, KCET 2017
Which one of the following is NOT a copolymer?

Options:
A Neoprene
B PHBV
C Buna-S
D Butadiene-styrene

The correct answer is:
Neoprene

Solution:
A copolymer is a polymer formed when two (or more) different types of monomers are linked in the same polymer chain, as opposed to a homopolymer where only one monomer is used.

Topic: Chemistry, Polymers, JEE Main, JEE Main 2022 (28 Jun Shift 1)
Which one of the following is not a gaseous biogeochemical cycle in ecosystem?

Options:
A Sulphur cycle
B Phosphorus cycle
C Nitrogen cycle
D Carbon cycle

The correct answer is:
Phosphorus cycle

Solution:
Phosphorus cycle is a sedimentary biogeochemical cycle. It describes the movement of phosphorus through the lithosphere, hydrosphere and biosphere and the main reservoir pool is lithosphere. Atmosphere does not play any significant role in the movement of phosphorus because phosphorus and phosphorus based compounds are usually solids at the typical ranges of temperature and pressure found on Earth. The production of phosphine gas occurs only in specialized, local conditions.

Topic: Biology, Ecosystem, NEET, NEET 2012 (Screening)
Which one of the following is not a part of a transcription unit in DNA?

Options:
A The inducer
B A terminator
C A promoter
D The structural gene

The correct answer is:
The inducer

Solution:
Transcription of DNA results in a mRNA encoding at least one gene. The mRNA however, serve as a template for protein synthesis through translation. Transcription unit is a specific section of DNA which is transcribed into mRNA. The transcription unit has three main parts; a promoter, a structural gene and a terminator. Thus, the correct answer is option A.

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2012 (Screening)
Which one of the following is not a plastid?

Options:
A Aleuoplast
B Chromoplast
C Chloroplast
D Aleurone

The correct answer is:
Aleurone

Solution:
Plastids are membrane bound organelles found in cells of plants, algae and some other organisms from eukaryotic group. These organelles are involved in either making food or storage of food. Plastids are further divided into groups as leucoplast, chromoplast and chloroplast. Chloroplast is involved in making food via photosynthesis. Leucoplast are colourless organelles mainly for storage and it is further grouped as amyloplast, elaioplast and aleuroplast. Chromoplast is an organelle that provides colour containing yellow or orange pigment.

Topic: Biology, Cell - The Unit of Life, NEET
Which one of the following is not a property of cancerous cells, whereas the remaining three are?

Options:
A They compete with normal cells for vital nutrients
B They do not remain confined in the area of formation
C They divide in an uncontrolled manner
D They show contact inhibition

The correct answer is:
They show contact inhibition

Solution:
Contact inhibition is the natural process of arresting cell growth when two or more cells come in contract with each other. It is a property of normal cells. Cancer cells divide in uncontrolled manner and do not show contact inhibition.

Topic: Biology, Human Health and Diseases, NEET, NEET 2012 (Screening)
Which one of the following is not a property of physical adsorption?

Options:
A Higher the pressure, more the adsorption
B Greater the surface area, more the adsorption
C Lower the temperature, more the adsorption
D Unilayer adsorption occurs

The correct answer is:
Unilayer adsorption occurs

Solution:
Physical adsorption increases with an increase in pressure. It also increases with the surface area. As adsorption is exothermic process so as temperature decreases, adsorption increases. It is a multilayer adsorption.

Topic: Chemistry, Surface Chemistry, JEE Main, JEE Main 2018 (16 Apr Online)
Which one of the following is not an application of green chemistry?

Options:
A Replacement of \( \mathrm{CFCs} \) by \( \mathrm{CO}_{2} \) as blowing agent in the manufacture of polystyrene foam sheets.
B Reacting methylamine and phosgene to produce methyl isocyanate.
C Replacement of organotins by 'sea-nine' as anti fouling compound in sea marines.
D Catalytic dehydrogenation of the diethanol amine without using cyanide and formaldehyde.

The correct answer is:
Reacting methylamine and phosgene to produce methyl isocyanate.

Solution:
Methyl isocyanate is highly toxic and irritating material

Topic: Chemistry, Environmental Chemistry, JEE Main
Which one of the following is not an essential mineral element for plants while the remaining three are?

Options:
A	Iron
B Manganese
C Cadmium
D Phosphorus

The correct answer is:
Cadmium

Solution:
Cadmium is not an essential element for plants. Phosphorus is macronutrient, iron and manganese are micronutrients required by plants for growth.

Topic: Biology, Mineral Nutrition, NEET
Which one of the following is not an essential mineral elements for plants while the remaining three are?

Options:
A Iron
B Manganese
C Cadmium
D Phosphorus

The correct answer is:
Cadmium

Solution:
Cadmium is not an essential element to plants.

Topic: Biology, Mineral Nutrition, NEET, NEET 2011 (Mains)
Which one of the following is not an example of calcination?

Options:
A CaCO3→∆CaO+CO2
B Fe2O3.xH2O→∆Fe2O3+xH2O
C 2PbS+3O2→∆2PbO+2SO2
D CaCO3.MgCO3→∆CaO+MgO+2CO2

The correct answer is:
2PbS+3O2→∆2PbO+2SO2

Solution:
Calcination is a process in which ore is heated in the absence of air or air might be supplied in a limited quantity.

Roasting involves the heating of ore lower than its melting point in the presence of air or oxygen.

2PbS+3O2→∆2PbO+2SO2

The above reaction is an example of roasting. Rest all the reactions are heated in the absence of oxygen.

Topic: Chemistry, General Principles and Processes of Isolation of Metals, JEE Main, JEE Main 2023 (15 Apr Shift 1)
Which one of the following is not coloured?

Options:
A \( C u^{2+} \)
B \( C u^{+} \)
C \( N i^{2+} \)
D \( F e^{3+} \)

The correct answer is:
\( C u^{+} \)

Solution:
Transition metal having electronic configuration n-1d1-9 forms coloured ion.
Cu2+Z=29:Ar3d9
Cu+Z=29:Ar3d10
Ni2+Z=28:Ar3d8
Fe3+Z=26:Ar3d5
Hence, Cu+ ion is not coloured.

Topic: Chemistry, d and f Block Elements, JEE Main
Which one of the following is not considered as a part of the endomembrane system?

Options:
A Golgi complex
B Peroxisome
C Vacuole
D Lysosome

The correct answer is:
Peroxisome

Solution:
Cell organelles, whose functions are coordinated, are considered together as an endomembrane system. The endomembrane system includes endoplasmic reticulum (ER), Golgi complex, lysosomes and vacuoles. Since the functions of the mitochondria, chloroplast and peroxisomes are not coordinated with the above components, these are not considered as part of the endomembrane system.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2011 (Mains)
Which one of the following is not correct?

Options:
A The work done on the evening primrose by Hugo deVries laid the foundation of the mutation theory.
B Single-step large mutations are known as saltation and were considered to be the main factor in causing speciation.
C Darwin advocated that variations are always large but heritable changes.
D Branching descent and natural selection are the two key concepts of the Darwinian Theory of Evolution.

The correct answer is:
Darwin advocated that variations are always large but heritable changes.

Solution:
Charles Darwin gave the theory of evolution based and believed that evolutionary changes are slow and gradual process. He suggested that variations occurring in the organisms whether large or small tend to be heritable. These variations gradually lead to the formation of new species. Hugo de Vries gave the theory of mutation based on his work on evening primrose.

Topic: Biology, Evolution, NEET
Which one of the following is not correct for the features of exponential function given by
\( \mathrm{f}(x)=b^{x} \) where \( \mathrm{b}>1 ? \)

Options:
A The domain of the function is \( R \), the set of real numbers.
B The range of the function is the set of all positive real numbers.
C For very large negative values of \( x \), the function is very close to \( 0 \).
D The point \( (1,0) \) is always on the graph of the function.

The correct answer is:
The point \( (1,0) \) is always on the graph of the function.

Solution:
Given function $f(x)=b^{x}$
Let $y=b^{x} \rightarrow(1)$
At $x=0$, we have $y=1$
At $x=1$, we have $y=b$
So, $(1,0)$ does not satisfy equation (1)
Hence,option (4) is not correct

Topic: Mathematics, Properties of Triangles, KCET, KCET 2014
Which one of the following is not correct with regard to the harmful effects of particulate matter of the size 2.5 micro meters or less?

Options:
A It can cause respiratory problems.
B It can directly enter into our circulatory system.
C It can cause inflammation and damage to the lungs.
D It can be inhaled into the lungs.

The correct answer is:
It can directly enter into our circulatory system.

Solution:
Particulate matter is divided into its sizes. Settleable $(\mathrm{PM}>10 \mu \mathrm{m})$ and suspended (PM < $10 \mu \mathrm{m})$. Particles less than $2.5 \mu \mathrm{m}$ diameter are most harmful. They pass deep into lungs, causing respiratory problem, cause inflammation and damage to the lungs. It cannot directly enter into our circulatory system, but through respiratory system.
Related Theory
Air Quality is measured using a metric called Air Quality Index (AQI). AQI will display the changes in air pollution in the atmosphere. Clean air is extremely important to maintain good health and the environment. Our atmosphere is predominantly made up of two important gases that are vital for life on earth, these are Oxygen and Nitrogen. Central Pollution Control Board (CPCB) has developed this Air Quality Index in consultation with IIT-Kanpur and air quality-professionals and experts. The most common measurement used to measure air
quality is PM 2.5 and PM 10. It measures the particles in micrograms per cubic metre.

Topic: Biology, Environmental Issues, NEET, NEET 2013 (Karnataka)
Which one of the following is not observed in biodiversity hotspots?

Options:
A Species richness
B Endemism
C Accelerated species loss
D Lesser inter-specific competition

The correct answer is:
Lesser inter-specific competition

Solution:
Lesser inter-specific competition : Due to the presence of high species diversity the inter specific competition will be more enhanced.

Topic: Biology, Biodiversity and its Conservation, NEET, NEET 2008 (Mains)