datavorous/entrance-exam-dataset huggingface dataset:
Which one of the following cannot be explained on the basis of Mendel's Law of Dominance?

Options:
A The discrete unit controlling a particular character is called a factor
B Out of one pair of factors one is dominant, and the other recessive
C Alleles do not show any blending and both the characters recover as such in $\mathrm{F}_2$ generation
D Factors occur in pairs

The correct answer is:
Alleles do not show any blending and both the characters recover as such in $\mathrm{F}_2$ generation

Solution:
The law of dominance does not occur universally. After Mendel several cases were recorded by scientists, where a clear deviation from law of dominance was seen. Such a deviation may be seen in the form of Incomplete dominance or Blending inheritance and Co-dominance.
Where $F_1$ hybrids exhibited a mixture or blending of character of two parents, the case is considered as that of incomplete dominance blending inheritance. It simply means that two genes of allelomorphic pair are not related as dominant or recessive, but each of them expresses itself partially. In the case of 4 o'clock plant, when plants with red flowers are crossed with plants having white flower, the $\mathrm{F}_1$ hybrids bear pink flower. When these pink flowers are self pollinated, they develop red, pink and white flowers in the ratio of $1: 2: 1$ respectively.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2010 (Screening)
Which one of the following cannot be explained on the basis of Mendel's Law of Dominance?

Options:
A The discrete unit controlling a particular character is called a factor
B Out of one pair of factors one is dominant, and the other recessive
C Alleles do not show any blending and both the characters recover as such in F2 generation.
D All of the inheritable factors occur in pairs.

The correct answer is:
Alleles do not show any blending and both the characters recover as such in F2 generation.

Solution:
According to Mendel's law of Dominance, out of two contrasting allelomorphic factors only one expresses itself in an individual. The factor that expresses itself is called dominant while the other which has not shown its effect in the heterozygous individual is termed as recessive The option Alleles do not show any blending and both the characters recover as such in F2 generation in the given question cannot be explained on the basis of law of dominance. It can only be explained on the basis of Mendel's law of independent assortment, according to which in a dihybrid cross, the two alleles of each character assort independently of the alleles of other character and separate at the time of gamete formation.

Topic: Biology, Principles of Inheritance and Variation, NEET
Which one of the following categories of animals, is correctly described with no single exception in it?

Options:
A All reptiles possess scales, have a three-chambered heart and are poikilothermal.
B All bony fishes have four pairs of gills and an operculum on each side.
C All sponges are marine and have collared cells.
D All mammals are viviparous and possess diaphragm for breathing.

The correct answer is:
All bony fishes have four pairs of gills and an operculum on each side.

Solution:
A All reptiles possess scales and are poikilothermal. They have a three chambered heart EXCEPT Crocodile, which has a four-chambered heart.
B Bony fishes belong to the Class Osteicthyes of Phylum Chordata. All fishes belonging to this class have four pair of gills and an operculum on each side. There is no exception in them.
C Sponges belong to the Phylum Porifera. They have collared cells known as chanocytes. Sponges are generally marine but some of them may even be found in fresh water. Eg: Spongilla is a fresh water sponge.
D Mammals possess a diaphragm for breathing. They are generally viviparous EXCEPT Platypus (Orinthorhynchus) which is an oviparous mammal.
Thus, option B is the correct option.

Topic: Biology, Animal Kingdom, NEET
Which one of the following cell organelles are enclosed by a single membrane?

Options:
A Mitochondria
B Chloroplasts
C Lysosomes
D Nuclei

The correct answer is:
Lysosomes

Solution:
Lysosomes are the unit membrane-bound vesicular structures formed by the process of packaging in the Golgi apparatus rich in hydrolytic enzymes like hydrolases, lipases, proteases, carbohydrases, and nucleases which are optimally active at the acidic pH. These enzymes are capable of digesting carbohydrates, proteins, lipids,, and nucleic acids.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2016 (Phase 1)
Which one of the following cell organelles are enclosed by a single membrane?

Options:
A Mitochondria
B Chloroplasts
C Lysosomes
D Nuclei

The correct answer is:
Lysosomes

Solution:
Lysosomes are the unit membrane-bound vesicular structures formed by the process of packaging in the Golgi apparatus rich in hydrolytic enzymes like hydrolases, lipases, proteases, and carbohydrases, which are optimally active at the acidic pH. These enzymes are capable of digesting carbohydrates, proteins, lipids and nucleic acids.

Topic: Biology, Cell - The Unit of Life, NEET
Which one of the following cell types always divides by anticlinal cell division?

Options:
A Fusiform initial cells
B Root cap
C Protoderm
D Phellogen

The correct answer is:
Protoderm

Solution:
Protoderm cells always divide by anticlinal cell division.

Topic: Biology, Anatomy of Flowering Plants, NEET
Which one of the following cellular parts is correctly described?

Options:
A Ribosomes those on chloroplasts are larger (80S) while those in the cytoplasm are smaller (70S)
B Centrioles sites for active RNA synthesis
C Thylakoids flattened membranous sacs forming the grana of chloroplasts
D Lysosomes optimally active at a pH of about 8.5

The correct answer is:
Thylakoids flattened membranous sacs forming the grana of chloroplasts

Solution:
Thylakoid are the flattened saclike membranous that are stacked on top of one another to form the grana of plant chloroplast. Chlorophyll and other photosynthetic pigments are situated in the thylakoid membranes, which are the site for the light reaction of photosynthesis.

Topic: Biology, Cell - The Unit of Life, NEET
Which one of the following cellular parts is correctly described?

Options:
A Centrioles - Sites for active RNA synthesis
B Lysosomes - Optimally active at a pH of about 8.5
C Thylakoids - Flattened membranous sacs forming the grana of chloroplasts.
D Ribosomes - Those on chloroplasts are larger (80S) while those in the cytoplasm are smaller (70S).

The correct answer is:
Thylakoids - Flattened membranous sacs forming the grana of chloroplasts.

Solution:
Centrioles serve as basal bodies for cilia and flagella. They are concerned with spindle formation during cell division. Lysosomes are membrane-bound organelles containing many hydrolytic enzymes, which are optimally active at an acid pH (near pH 5). Thylakoids are membrane - bound organelles found within chloroplasts. The thylakoid membrane, forms many flattened, fluid-filled tubules that enclose a single convoluted compartment. These tubules tend to stack on top of each other to forma structure called a granum.

Topic: Biology, Cell - The Unit of Life, NEET
Which one of the following characteristics is associated with adsorption?

Options:
A ∆G is negative but ∆H and ∆S are positive
B ∆G,∆H and ∆S all are negative
C ∆G and ∆H are negative but ∆S is positive
D ∆G and ∆S are negative but ∆H is positive

The correct answer is:
∆G,∆H and ∆S all are negative

Solution:
∆H<0 Adsorption process is exothermic
∆G<0 Adsorption process is Feasible
∆S<0 Adsorption process is accompanied of decrease in entropy.

Topic: Chemistry, Surface Chemistry, NEET, NEET 2016 (Phase 1)
Which one of the following characteristics is not shared by birds and mammals?

Options:
A Ossified endoskeleton
B Breathing using lungs
C Viviparity
D Warm blooded nature

The correct answer is:
Viviparity

Solution:
Birds are oviparous while mammals are oviparous (prototherians) and viviparous (metatherians and eutherians). Oviparous- producing young by means of eggs which are hatched after they have been laid by the parent, as in birds. Viviparous- bringing forth live young which have developed inside the body of the parent.

The only oviparous mammal is platypus.

Topic: Biology, Animal Kingdom, NEET, NEET 2016 (Phase 1)
Which one of the following characteristics of the transition metals is associated with their catalytic activity?

Options:
A High enthalpy of atomization
B Paramagnetic behaviour
C Colour of hydrated ions
D Variable oxidation states

The correct answer is:
Variable oxidation states

Solution:
Transition elements are elements that have partially filled d-orbitals. These elements show variable oxidation state because their valence electrons in two different sets of orbitals, that is (n-1)d and $\mathrm{ns}$. The energy difference between these orbitals is very less, so both the energy levels can be used for bond formation. Thus, transition elements have variable oxidation states.
Related Theory
The presence of unpaired electrons leads to the formation of metal-metal covalent bonds along with the metallic bonds. These strong bonds attribute high melting and boiling points to the elements. The presence of a partially filled $d$-orbital enables the transition elements to have a greater number of unpaired electrons, which in turn increases their ability to form covalent bonds along with metallic bonds.

Topic: Chemistry, d and f Block Elements, NEET, NEET 2003
Which one of the following characteristics of the transition metals is associated with their catalytic activity ?

Options:
A High enthalpy of atomization
B Paramagnetic behaviour
C Colour of hydrated ions
D Variable oxidation states

The correct answer is:
Variable oxidation states

Solution:
The transition elements, on account of their variable valency, are able to form unstable intermediate compounds very readily.

Topic: Chemistry, d and f Block Elements, NEET
Which one of the following characters is not typical of the class mammalia?

Options:
A thecodont dentition
B alveolar lungs
C ten pairs of cranial nerves
D seven cervical vertebrae.

The correct answer is:
ten pairs of cranial nerves

Solution:
In higher vertebrates (reptiles, birds, mammals) there are 12 pairs of cranial nerves which fish and ambhibian have 10 pairs of cranial nerves. Alveolar lungs, seven cervical vertebrae, and thecodont dentition are typical of class Mammalia.

Topic: Biology, Animal Kingdom, NEET, NEET 2005
Which one of the following classes is incorrectly matched with its two general characters?

Class	Characteristics

(i)	Amphibia	Urinary bladder present, fertilization external

(ii)	Chondrichthyes	Air bladder, operculum

(iii)	Cyclostomata	Closed circulation, 6-15 pairs of gill slits

(iv)	Reptiles	Cornified skin, direct development

Options:
A (i)
B (ii)
C (iii)
D (iv)

The correct answer is:
(ii)

Solution:
Chondrichthyes are cartilaginous fish. They include shark, rays etc. These Chondrichthyes lack operculum, which is external covering on the gills and they also lack air bladder because of which they have to swim constantly to avoid sinking. Operculum and air bladder are found in all of the Osteichthyes (bony fish).

Topic: Biology, Animal Kingdom, NEET
Which one of the following common sexually transmitted diseases is completely curable when detected early and treated properly?

Options:
A HIV infection
B Genital herpes
C Gonorrhoea
D Hepatitis-B

The correct answer is:
Gonorrhoea

Solution:
The sexually transmitted infections (STI) or venereal diseases (VD) or reproductive tract infections (RTI) are infections or diseases which are transmitted through sexual intercourse. Among these, HIV infection is most dangerous which is caused by retrovirus.

Except for hepatitis-B, genital herpes and HIV infections, other diseases like Gonorrhoea, etc. are completely curable if detected early and treated properly. Gonorrhoea is caused by a bacterium, Neisseria gonorrhoeae, which infects the mucous membranes of the reproductive tract, including the cervix, uterus, and fallopian tubes in female and the urethra in women and men.

Topic: Biology, Reproductive Health, NEET, NEET 2023 (All India)
Which one of the following complexes shows optical isomerism? (en=ethylendiamine)

Options:
A transÂ Coen2Â Cl2Â Cl
B CoNH34 Cl2 Cl
C CoÂ NH33Â Cl3
D cis Coen2 Cl2Cl

The correct answer is:
cis Coen2 Cl2Cl

Solution:
Geometrical isomer
cis Coen2Cl2Cl
trans coen2Cl2Cl
Cis trans

Topic: Chemistry, General Organic Chemistry, NEET
Which one of the following compound is a peroxide?

Options:
A NO2
B KO2
C BaO2
D MnO2

The correct answer is:
BaO2

Solution:
In peroxides oxidation number of oxygen is -1, in superoxide it is -12 and in oxides it is -2.
Here BaO2 is peroxide, KO2 is superoxide and NO2 , MnO2 are oxides.

Topic: Chemistry, s Block Elements, NEET
Which one of the following compound is non - benzenoid?

Options:
A
B
C
D

The correct answer is:

Solution:
This Compound is Quasi aromatic but it has no benzene ring so it is non-benzoid. Rest all are benzoid.

Topic: Chemistry, General Organic Chemistry, NEET
Which one of the following compound is not a planar?

Options:
A
B
C
D

The correct answer is:

Solution:
Here hybridisation of oxygen is sp3. so it cannot be a planar molecule. In it lone pair of oxygen does not involve in delocalisation, otherwise it will become antiaromatic compound. Rest other are planar as they have only sp2 hybridisation.

Topic: Chemistry, General Organic Chemistry, NEET
Which one of the following compounds does not show tautomerism?

Options:
A CH3–CH2–NO2
B
C
D

The correct answer is:

Solution:
This compound does not have any α -H-atom so it cannot show tautomerism.
Rest other compounds have α -H-atom/s so they can show tautomerism. For example,

Topic: Chemistry, General Organic Chemistry, NEET
Which one of the following compounds gives carboxylic acid with HNO2

Options:
A
B C6H5CONH2
C
D CH3COOC2H5

The correct answer is:
C6H5CONH2

Solution:
Benzamide on reaction with nitrous acid gives benzoic acid as follows

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
Which one of the following compounds has iodine in its the highest oxidation state?

Options:
A KI
B KI3
C IF5
D KIO4

The correct answer is:
KIO4

Solution:
KIO 4
1+x-2×4=0 ; x=8-1=+7 .

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Which one of the following compounds has the most acidic nature?

Options:
A

B

C

D

The correct answer is:

Solution:
Key Idea Presence of electron withdrawing substituent increases the acidity while electron releasing substituent, when present, decreases the acidity.
Phenyl is an electron withdrawing substituent while $-\mathrm{CH}_3$ is an electron releasing substituent. Moreover, phenoxide ion is more resonance stabilised as compared to benzyloxide ion, thus releases proton more easily. That's why is a strong acid among the given.

Topic: Chemistry, General Organic Chemistry, NEET, NEET 2010 (Screening)
Which one of the following compounds has the most acidic nature?

Options:
A
B
C
D

The correct answer is:

Solution:
Here is most acidic as in it (Phenoxide ion) is resonance stabilized while rest other are alcohols and alkoxide ion is less stable as no resonance is possible hence they are less acidic than phenol.

Topic: Chemistry, General Organic Chemistry, NEET
Which one of the following compounds is a peroxide?

Options:
A $\mathrm{KO}_2$
B $\mathrm{BaO}_2$
C $\mathrm{MnO}_2$
D $\mathrm{NO}_2$

The correct answer is:
$\mathrm{BaO}_2$

Solution:
Key Idea:- In peroxides, the oxidation state of $O$ is - 1 and they give $\mathrm{H}_2 \mathrm{O}_2$, with dilute acids, and have peroxide linkage.
In $\mathrm{KO}_2$,
$$
+1+(\mathrm{x} \times 2)=0
$$
$x=-\frac{1}{2}$ (thus, it is a superoxide, not $a$ peroxide.)
In $\mathrm{BaO}_2$,
$$
\begin{aligned}
& +2+(\mathrm{x} \times 2)=0 \\
& \mathrm{x}=-1
\end{aligned}
$$
Thus, it is a peroxide. Only it gives $\mathrm{H}_2 \mathrm{O}_2$ when reacts with dilute acids and has peroxide linkage as
$$
\begin{aligned}
& \mathrm{Ba}^{2+}[\mathrm{O}-\mathrm{O}]^{2-} \\
& \text { peroxide linkage }
\end{aligned}
$$
In $\mathrm{MnO}_2$ and $\mathrm{NO}_2, \mathrm{Mn}$ and $\mathrm{N}$ exhibit variable oxidation states, thus, the oxidation state of $O$ in these is -2 . Hence, these are not peroxides. Thus, it is clear, that among the given molecules only $\mathrm{BaO}_2$ is a peroxide.

Topic: Chemistry, s Block Elements, NEET, NEET 2010 (Screening)
Which one of the following compounds is a peroxide?

Options:
A KO2
B BaO2
C MnO2
D NO2

The correct answer is:
BaO2

Solution:
BaO2 has peroxide linkage.(Ba+2 O 2 â2 )

Topic: Chemistry, s Block Elements, NEET
Which one of the following compounds is different from the rest in terms of undergoing hydrolysis to form simpler compounds?

Options:
A Sucrose
B Maltose
C Lactose
D Glucose

The correct answer is:
Glucose

Solution:
(i) Monosaccarides cannot undergo hydrolysis.
(ii) Disaccarides are carbohydrates which give two monosaccarides unit on hydrolysis.
Sucrose + H 2 Oâ Glucose + Fructose
Maltose + H 2 Oâ 2 Glucose
Lactose + H 2 Oâ Glucose + Galactose
Glucose cannot undergo hydrolysis.

Topic: Chemistry, Biomolecules, NEET
Which one of the following compounds is least reactive with water?

Options:
A
B
C
D

The correct answer is:

Solution:
Amide is least reactive with water among acid derivatives.
We know that less is the stability of carbocation of acid derivative, more is its reactivity. Hence acetamide is reactive than benzamide.

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
Which one of the following compounds is least reactive with water?

Options:
A
B
C
D

The correct answer is:

Solution:
Here benzamide is least reactive acid derivative for hydrolysis reaction as
As less is the stability of carbocation of acid derivative, more is its reactivity so acetamide is more reactive than benzamide here.

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
Which one of the following compounds is most acidic?

Options:
A

B

C

D

The correct answer is:

Solution:
Phenols are more acidic than alcohols, due to the stabilization of phenoxide ion via resonance.
Ortho nitrophenol is most acidic of all because $-\mathrm{NO}_2$ is a electron withdrawing group. Thus, $\mathrm{NO}_2$ stabilise of negative charge on the oxygen of phenoxide ion. On the other hand, $\mathrm{CH}_3$ group is a electron donating group. Thus, acidic strength of phenol is decreased in cresol due to destabilisation of phenoxide ion.
Thus, correct order is:
Caution
$\Rightarrow$ Phenoxide ion is stabilized due to following resonating structures:

Topic: Chemistry, Hydrocarbons, NEET, NEET 2005
Which one of the following compounds is not a protonic acid?

Options:
A $\mathrm{B}(\mathrm{OH})_3$
B $\mathrm{PO}(\mathrm{OH})_3$
C $\mathrm{SO}(\mathrm{OH})_2$
D $\mathrm{SO}_2(\mathrm{OH})_1$

The correct answer is:
$\mathrm{B}(\mathrm{OH})_3$

Solution:
Boric acid is not a protic acid. Boric acid is a weak monobasic acid. It is not a protonic acid but acts as a Lewis acid by accepting electrons from a hydroxyl ion and in turn releases $\mathrm{H}^{+}$ ions
Related Theory
Although Boric acid contains $3 \mathrm{OH}$ groups yet it can act as monobasic acid rather than tribasic acid, since, only one $\mathrm{H}^{+}$can be released by a water molecule.

Topic: Chemistry, Ionic Equilibrium, NEET, NEET 2003
Which one of the following compounds on dehalogenation gives 2, 3-dimethyl-but-2-ene?

Options:
A
B CH3-(CH2)4-CHCl2
C CH3-CH2-CHCl2
D CH2Cl-(CH2)4-CH2Cl

The correct answer is:

Solution:
on dehalogenation gives 2, 3-dimethyl-but-2-ene as follows

Topic: Chemistry, Hydrocarbons, NEET
Which one of the following compounds show optical activity

Options:
A
B
C
D

The correct answer is:

Solution:
It has two chiral carbons and the molecule has no plane of symmetry so it is optically active.
Rest all molecules have two chiral carbons atoms and the molecules have plane of symmetry also so they are optically inactive.

Topic: Chemistry, General Organic Chemistry, NEET
Which one of the following compounds shows both, Frenkel as well as Schottky defects?

Options:
A AgBr
B AgI
C NaCl
D ZnS

The correct answer is:
AgBr

Solution:
It is known that Schottky defects arise due to missing of ions from their lattice point and Frenkel defects arise when the missing ions occupy the interstitial sites.

Now for the case of AgBr, we know that the radius of AgBr being intermediate, hence it shows both Frenkel and Schottky defects.

The major defect that occurs in AgBrAgBr is the Frenkel defect. It has ccp lattice, The larger halide ions are arranged in a cubic close-packing, while the smaller silver ions fill the octahedral gaps between them, giving a 6-coordinate structure where a silver ion Ag+ is surrounded by 6 Br− ions, and vice versa.

Ag moves from octahedral to tetrahedral sites thereby causing only cations to precipitate.

Also, Schottky defect in AgBr is exhibited due to precipitation of both cations and anions. Finally, the Ag+ ion is small in size in AgBr and therefore when removed from lattice point it can occupy interstitial site and hence show both Frenkel and Schottky defects.

Topic: Chemistry, Solid State, NEET, NEET 2020 (Phase 2)
Which one of the following compounds shows the presence of intramolecular hydrogen bond?

Options:
A H2O2
B HCN
C Cellulose.
D Concentrated acetic acid.

The correct answer is:
Cellulose.

Solution:
In cellulose, intramolecular hydrogen bonding is present. This is due to the fact that the glucose monomers form straight chains. Thus, its polymeric structure crowd together, showing intramolecular H-bonding.

Topic: Chemistry, Biomolecules, NEET, NEET 2016 (Phase 2)
Which one of the following compounds undergoes predominantly S N 2 reaction with aqueous NaOH in a polar aprotic solvent?

Options:
A
B
C
D

The correct answer is:

Solution:
Rate of S N 2 reaction ∝-M,-I power.

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
Which one of the following concerns photophosphorylation?

Options:
A ADP + AMP $\stackrel{\text { Light energy }}{\longrightarrow}$ ATP
B $\mathrm{ADP}+$ Inorganic $\mathrm{PO}_4 \stackrel{\text { Light energy }}{\longrightarrow}$ ATP
C $\mathrm{ADP}+$ lnorganic $\mathrm{PO}_4 \longrightarrow$ ATP
D $\mathrm{AMP}+$ lnorganic $\mathrm{PO}_4 \stackrel{\text { Light energy }}{\longrightarrow}$ ATP

The correct answer is:
$\mathrm{ADP}+$ Inorganic $\mathrm{PO}_4 \stackrel{\text { Light energy }}{\longrightarrow}$ ATP

Solution:
Photophosphorylation is the process in which ATP is produced, which is called as energy currency of the cell. During this process, ADP is phosphorylated to give ATP in presence of light energy.
Related Theory
During photophosphorylation, electrons move from water through PSII, intermediate chain of carriers, through PSI, and finally to $\mathrm{NADP}+$ causing its reduction into NADPH2. Flow of electrons through the carriers linking PSII and PSI pump protons into the thylakoid lumen.

Topic: Biology, Photosynthesis in Higher Plants, NEET, NEET 2003