datavorous/entrance-exam-dataset huggingface dataset:
Which of the following carbides reacts with H2O to form propane?

Options:
A Al4C3
B CaC2
C SiC
D Mg2C3

The correct answer is:
Mg2C3

Solution:
Mg2C3+4HOH→CH3-C≡CH+2Mg(OH)2
A. Al4C3+12HOH→3CH4+4Al(OH)3
B. CaC2+2HOH→CH≡CH+Ca(OH)2
C. SiC+HOH→ No reaction.

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET
Which of the following carbocation can not undergo rearrangement?

Options:
A
B
C
D

The correct answer is:

Solution:
Here only carbocation given in option C do not undergo rearrangement as it is more stable carbocation. In rest other carbocations rearrangement is possible as follows
A.
B.
D. C6H5-CH2-C⊕H2→1,2-H⊕shiftC6H5-C⊕H-CH3

Topic: Chemistry, General Organic Chemistry, NEET
Which of the following carbocations is expected to be most stable?

Options:
A
B
C
D

The correct answer is:

Solution:
In B, C and D positive charge is/will be directly on carbon adjacent to − NO 2 group which is a strong electron withdrawing group.

Topic: Chemistry, General Organic Chemistry, NEET
Which of the following carbocations is expected to be the most stable?

Options:
A
B
C
D

The correct answer is:

Solution:
NO2 is present at the ortho- and the para- position of a positive charge.

NO2 present at the meta-position of a positive charge is less stable due to the e- withdrawing effect of -NO2 (-I effect of NO2)
NO2 present at the ortho- and para- of positive charge (Less stable due to the e- withdrawing effect of -NO2 (-M effect.)
The positive charge is destabilized by the electron-withdrawing groups.
-M dominates -I effect. So, the carbocation which has -I group is more stable.

Topic: Chemistry, General Organic Chemistry, NEET, NEET 2018
Which of the following carbocations is most stable?

Options:
A I
B II
C III
D IV

The correct answer is:
II

Solution:
Stability of carbocationâMagnitude of +I & hyperconjugation
Hypercojugation â number of Î±-H-atom

Topic: Chemistry, General Organic Chemistry, NEET
Which of the following carbocations would not likely rearrange to a more stable carbocation?

Options:
A
B
C
D None of these

The correct answer is:

Solution:
Rearrangement in this case will not yield a carbocation of degree higher than 2.

Topic: Chemistry, General Organic Chemistry, NEET
Which of the following carbohydrate is a reducing sugar?

Options:
A Maltose
B Glucose
C Galactose
D All of above

The correct answer is:
All of above

Solution:
A sugar is classified as a reducing sugar only if it has an open-chain form with an aldehyde group or a free hemiacetal group. Monosaccharides which contain an aldehyde group are known as aldoses, and those with a ketone group are known as ketoses. All monosaccharides are called reducing sugars.

Topic: Chemistry, Biomolecules, NEET
Which of the following carbohydrates is called an invert sugar?

Options:
A Fructose
B Glucose
C Cellulose
D Sucrose

The correct answer is:
Sucrose

Solution:
Correct Option is : (D)
Sucrose

Topic: Chemistry, Biomolecules, NEET
Which of the following carbonate salt is soluble due to high entropy change?

Options:
A K2CO3
B Li2CO3
C (NH4)2CO3
D Na2CO3

The correct answer is:
(NH4)2CO3

Solution:
ΔHsol of ammonium salts are found to be positive but they are highly soluble due to high positive entropy change it makes ΔGsol more negative according to equation
ΔGsol=ΔHsol-TΔSsol

Topic: Chemistry, Thermodynamics (C), NEET
Which of the following carbonyl compounds will give racemisation reaction in the presence of acid or base?

Options:
A
B
C
D

The correct answer is:

Solution:
Here the compound given below (Option B) can show racemisation as it has α -carbon atom as chiral. when it reacts with HCN racemic product is formed

Topic: Chemistry, Aldehydes and Ketones, NEET
Which of the following carboxylic acid undergoes decarboxylation easily ?

Options:
A
B
C
D

The correct answer is:

Solution:
β-keto Acid on heating easily undergo decarboxylation via a six-membered. Cyclic transition state.

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
Which of the following carboxylic acids is most reactive towards esterification?

Options:
A (CH3)3CCOOH
B (CH3)2CHCOOH
C CH3CH2COOH
D (C2H5)2CHCOOH

The correct answer is:
CH3CH2COOH

Solution:
CH3CH2COOH is most reactive towards esterification as C atom of carboxylic group is stericaly least hindered. Greater is the steric hinderance, lower is the reactivity.

Topic: Chemistry, Carboxylic Acid Derivatives, NEET
Which of the following catalyses the conversion of glucose into ethanol

Options:
A Zymase
B Invertase
C Maltase
D Diastase

The correct answer is:
Zymase

Solution:
C6H12O6Glucose→ZymaseEnzyme2C2H5OHEthanol+2CO2

Topic: Chemistry, Biomolecules, NEET
Which of the following causes an increase in sodium reabsorption in the distal convoluted tubule?

Options:
A Increase in aldosterone levels
B Decrease in antidiuretic hormone levels
C Decrease in aldosterone levels
D Increase in antidiuretic hormone levels

The correct answer is:
Increase in aldosterone levels

Solution:
Sodium absorption by the distal tubule is mediated by the hormone aldosterone. Aldosterone increases sodium reabsorption. Aldosterone is secreted by zona glomerulosa of adrenal cortex and also known as salt retaining hormone.

Topic: Biology, Excretory Products and their Elimination, NEET, NEET 2014
Which of the following causes malignant malaria?

Options:
A Plasmodium vivax
B Plasmodium falciparum
C Plasmodium ovale
D Plasmodium malaria

The correct answer is:
Plasmodium falciparum

Solution:
Plasmodium falciparum malaria is the most severe form of malaria, caused by Plasmodium falciparum, with severe constitutional symptoms and sometimes causing death.

Topic: Biology, Human Health and Diseases, NEET
Which of the following causes of the Evil Quartet involves the combined loss of a coevolved plant-pollinator mutualism?

Options:
A fragmentation
B alien species invasion
C over-exploitation
D co-extinction

The correct answer is:
co-extinction

Solution:
When a species becomes extinct, the plant and animal species associated with it in an obligatory way also become extinct. When a host fish species becomes extinct, its unique assemblage of parasites also meets the same fate. Another example is the case of a coevolved plant-pollinator mutualism where extinction of one invariably leads to the extinction of the other.

Topic: Biology, Biodiversity and its Conservation, NEET
Which of the following cell junction is the least permeable and prevents leakage across a tissue?

Options:
A Tight junctions
B Adhering junctions
C Gap junctions
D Intercalated disc

The correct answer is:
Tight junctions

Solution:
Tight junctions are also called as zona occludens. At certain places, the plasma membranes of adjacent cells are tightly packed or fused together. These are least permeable and prevent leakage across a tissue.

Topic: Biology, Structural Organisation in Animals, NEET
Which of the following cell junctions help in the rapid transfer of ions and molecules?

Options:
A Gap junctions
B Adhering junctions
C Synaptic junctions
D Tight junctions

The correct answer is:
Gap junctions

Solution:
In nearly all animal tissues, specialised junctions provide both structural and functional links between their individual cells. Three types of cell junctions are found in the epithelium and other tissues. These are called as tight, adhering and gap junctions. Tight junctions help to stop substances from leaking across a tissue. Adhering junctions perform cementing to keep neighbouring cells together. Gap junctions facilitate the cells to communicate with each other by connecting the cytoplasm of adjoining cells for rapid transfer of ions, small molecules and sometimes big molecules.

Topic: Biology, Structural Organisation in Animals, NEET
Which of the following cell junctions is highly permeable and cause easy passage of substance across the cell membranes?

Options:
A Tight junctions
B Adhering junctions
C Gap junctions
D Desmosomes

The correct answer is:
Gap junctions

Solution:
Gap junctions are aggregates of intercellular channels that permit direct cell-cell transfer of ions and small molecules.

Topic: Biology, Structural Organisation in Animals, NEET
Which of the following cell organelle is not present in plant cells but present in the animal cell?

Options:
A Cell wall
B Plastids
C Central vacuole
D Centrioles

The correct answer is:
Centrioles

Solution:
Plant and animal cell are different as the former possess cell wall, plastids and a large central vacuole which are absent in animal cell. On the other hand, animal cell have centrioles which are absent in almost all the plant cell.

Topic: Biology, Cell - The Unit of Life, NEET
Which of the following cell organelle of the eukaryotic cell shows fission?

Options:
A Endoplasmic reticulum
B Golgi body
C Lysosome
D Plastids

The correct answer is:
Plastids

Solution:
Plastid divides by fission to form pro plastid which further develops to form different type of plastid required by the cell. Mitochondria and plastid are similar and both divides by fission to increase their number.

Topic: Biology, Cell - The Unit of Life, NEET
Which of the following cell organelles are involved in the manufacturing of various substances?

Options:
A Lysosome, Vacuole, Ribosome
B Ribosomes, RER, SER
C Vacuole, RER, SER
D SER, Ribosome, Centriole

The correct answer is:
Ribosomes, RER, SER

Solution:
Ribosomes and rough endoplasmic reticulum (RER) is concerned with protein synthesis and smooth endoplasmic reticulum (SER) carries out lipid synthesis.
Lysosomes stores many lytic proteins and vacuoles are the carriers or cargo vescicles. Centrioles are present in the centrosomes and form spindles during cell division.

Topic: Biology, Cell - The Unit of Life, NEET
Which of the following cell organelles has the electron transport system?

Options:
A Organelle related to the oxidation of carbohydrates
B Organelle related to the synthesis of food
C Organelle related to the degradation of food
D a and b both

The correct answer is:
a and b both

Solution:
The electron transport system is present in mitochondria where oxidation of carbohydrates occurs to release energy which is trapped to formed ATP. It is also present in chloroplast were a synthesis of food occurs by photosynthesis, light energy is trapped to form ATP which is used in reduction of carbon to form glucose.

Topic: Biology, Respiration in Plants, NEET
Which of the following cell organelles is likely to be present in Euglena but not in Saccharomyces (yeast)?

Options:
A Nucleus
B Contractile vacuole
C Golgi body
D Mitochondria

The correct answer is:
Contractile vacuole

Solution:
Euglena is connecting link between plant and animal and lacks cell wall, it is fresh water organism thus consists of contractile vacuole for osmoregulation, whereas yeast consists of cell wall thus lacks contractile vacuole.

Topic: Biology, Biological Classification, NEET
Which of the following cell organelles is present in the highest number in secretory cells?

Options:
A Mitochondria
B Golgi complex
C Endoplasmic reticulum
D Lysosomes

The correct answer is:
Golgi complex

Solution:
Golgi complex (Golgi apparatus) is a cell organelle present in highest number in secretory cells. These are the site of modification, packaging and secretions of secretory proteins and glycoproteins outside the cell.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2019 (Odisha)
Which of the following cell organelles is responsible for extracting energy from carbohydrates to form ATP?

Options:
A Lysosome
B Ribosome
C Chloroplast
D Mitochondrion

The correct answer is:
Mitochondrion

Solution:
Mitochondria are rod-shaped organelles that can be considered the power generators of the cell, converting oxygen and nutrients into adenosine triphosphate (ATP). ATP is the chemical energy "currency" of the cell that powers the cell's metabolic activities through aerobic cellular respiration.

Ribosomes are involved in protein synthesis which is accomplished by mRNA and tRNA of the cells. Lysosomes help in digesting non-functional organelles. Chloroplasts also prepare ATP by cyclic and non-cyclic photophosphorylation during photosynthesis.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2017
Which of the following cells are responsible for the secretion of the hormone that stimulates muscular growth, growth of facial and axillary hair, aggressiveness, low pitch of voice, etc. in males?

Options:
A Cells which form the lining of seminiferous tubules
B Cells which provide nutrition to the growing spermatozoa
C Cells situated in the interstitial space of testis
D Germ cells

The correct answer is:
Cells situated in the interstitial space of testis

Solution:
Cells situated in the interstitial space of testis are known as 'leydig cells' or 'interstitial Cells'. These cells are responsible for the secretion of the androgen 'testosterone'. Testosterone is the hormone responsible for the development of male sexual characters. Adam's apple is the thickening of thyroid cartilage that causes a change in the voice of males at puberty. This happens under the effect of hormone testosterone.

Topic: Biology, Human Reproduction, NEET
Which of the following cells does not exhibit phagocytosis activity?

Options:
A Monocyte
B Neutrophil
C Basophil
D Macrophage

The correct answer is:
Basophil

Solution:
Basophil does not exhibit phagocytosis activity.

Topic: Biology, Body Fluids and Circulation, NEET
Which of the following cells is NOT a part of cellular barriers?

Options:
A Interferons
B Natural killer cell
C Kupffer cell
D Polymorphonuclear lymphocytes

The correct answer is:
Interferons

Solution:
Immunity can be classified as Innate and Acquired. Innate immunity is present since birth and consists of many barriers. These include Physical, Physiological and Cellular barriers. Cellular barriers include Interleukin, Interferons, White blood cells, Macrophages, Natural killer cells etc. Kupffer cells are macrophages of liver and polymorphonuclear cells are WBC and both are included in cellular barriers.
Cytokine barriers: Virus-infected cells secrete proteins called interferons which protect non-infected cells from further viral infection.

Topic: Biology, Human Health and Diseases, NEET
Which of the following cells is round and biconcave in shape?

Options:
A WBCs
B RBCs
C Epithelial Cells
D Nerve Cells

The correct answer is:
RBCs

Solution:
The shape of RBCs varies in different vertebrate classes. In mammals, they are circular, biconcave and enucleated discs. Their central part is thinner than the margins. This shape provides flexibility and results in 20-30% increased surface area.

Topic: Biology, Structural Organisation in Animals, NEET
Which of the following cells is usually dead and without a protoplasm?

Options:
A Parenchyma
B Sclerenchyma
C Aerenchyma
D Collenchyma

The correct answer is:
Sclerenchyma

Solution:
It is long,narrow cells with thick and lignified cell wall having a pits. They are usually dead and without protoplasts. They provides mechanical support to organ.

Topic: Biology, Anatomy of Flowering Plants, NEET
Which of the following cells of blastocyst acts as a precursor of the embryo?

Options:
A Trophoblast
B Inner cell mass
C Stem cells
D Both B & C

The correct answer is:
Inner cell mass

Solution:
Cleavage of zygote results in the formation of a 64 celled stage called Blastocysts, which contain outer group of cells called Trophoblasts and inner group of cells called Inner cell mass, which gets differentiated as the embryo.

Topic: Biology, Human Reproduction, NEET
Which of the following cells of human testis are present in the regions outside the seminiferous tubules but in the testicular lobules?

Options:
A Leydig cells
B Sertoli cells
C Nurse cells
D All of the above

The correct answer is:
Leydig cells

Solution:
Each seminiferous tubule is lined on its inner side by two types of cells called spermatogonium/make germ cells and Sertoli cells/Nurse cells.
Leydig cells or interstitial cells are present in the region outside the seminiferous tubules of testes. These secrete testosterone.

Topic: Biology, Human Reproduction, NEET
Which of the following cells produce factors that help in maturation of spermatids to spermatozoa?

Options:
A Leydig cells
B Sertoli cells
C Spermatogonia
D Both A and B

The correct answer is:
Sertoli cells

Solution:
Sertoli cells of a seminiferous tubule of testis secrete inhibin, a proteinaceous hormone, when sperm count is too high. This hormone causes negative feedback to suppress the overactivity of the FSH hormone to suppress spermatogenesis.
Also, FSH acts on the sertoli cells and stimulates the secretion of some factors which help in the process of spermiogenesis.

Topic: Biology, Human Reproduction, NEET
Which of the following cellular metabolic processes can occur both in the presence or absence of O2?

Options:
A Glycolysis
B Fermentation
C TCA cycle
D Electron transport coupled with chemiosmosis

The correct answer is:
Glycolysis

Solution:
Glycolysis is a catabolic process where the substrate glucose is broken down into smaller molecules- pyruvic acid and occurs anaerobically. The site for glycolysis is the cytoplasm. It is a stepwise process involving a series of ten enzymes to catalyze the processes. In it, some of the intermediates may get involved in other metabolic processes than respiration. Like DHAP formed can be used in the lipid synthesis as it is a source of glycerol to join fatty acids. It is the connecting link or common pathway between both types of respiration. In aerobic respiration, the oxygen molecule is not involved in the glycolysis pathway.

Topic: Biology, Respiration in Plants, NEET
Which of the following cellular organelles is/are bound by a single membrane?
Peroxisomes, Lysosomes, Mitochondria

Options:
A Only peroxisomes but not lysosomes and mitochondria
B Both peroxisomes and lysosomes but not mitochondria
C All of the three organelles
D None of the three organelles

The correct answer is:
Both peroxisomes and lysosomes but not mitochondria

Solution:
The lysosomes are bound by a single unit membrane of 75 A ∘ . The peroxisomes are also surrounded by a single unit membrane of about 60 A ∘ thickness. The mitochondria are surrounded by a double-layered membrane.

Topic: Biology, Cell - The Unit of Life, NEET
Which of the following changes in earlier classification systems were not brought about by R.H. Whittaker?

Options:
A Blue green algae are no longer considered as plants.
B Chlorella, a unicellular alga, is no longer considered as a plant.
C Amoeba and Paramoecium are no longer considered as animals.
D Yeast, a unicellular eukaryote, is no longer considered as fungus

The correct answer is:
Yeast, a unicellular eukaryote, is no longer considered as fungus

Solution:
R.H. Whittaker proposed a Five Kingdom Classification in 1969. According to him all unicellular prokaryotic organisms like Bacteria, BGA are included in Kingdom Monera and second kingdom Protista includes all unicellular eukaryotic organisms like Amoeba, Paramecium, etc., kingdom Fungi includes saprophytic, eukaryotic mostly multicellular organisms (except unicellular Saccharomyces cerevisiae). All multicellular organisms whose cell wall is made up of cellulose and pectin and are mostly autotrophic are included in plant kingdom. Kingdom Animalia includes multicellular organisms without cell wall and heterotrophic mode of nutrition.

Topic: Biology, Biological Classification, NEET
Which of the following changes represent a disproportionation reaction (s)?

Options:
A Cl2+2OH-âClO-+Cl-+H2O
B Cu2O+2H+âCu+Cu2++H2O
C 2HCuCl2âDilution withCu+Cu2++4Cl-+2H+
D All of these

The correct answer is:
All of these

Solution:
Here all reactions represent disproportionation reaction as in them a single species is undergoing both oxidation and reduction for e.g., Cl2+2OH-→ClO-+Cl-+H2O
Here chlorine is undergoing both oxidation and reduction.

Topic: Chemistry, Redox Reactions, NEET
Which of the following character is unique to Mollusca?

Options:
A Canal system
B Mantle cavity
C Pseudocoelom
D Collar cells

The correct answer is:
Mantle cavity

Solution:
Molluscs are terrestrial or aquatic (marine or fresh water) having an organ-system level of organisation. They are bilaterally symmetrical, triploblastic and coelomate animals. Body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot and visceral hump. A soft and spongy layer of skin forms a mantle over the visceral hump. The space between the hump and the mantle is called the mantle cavity in which feather like gills are present. They have respiratory and excretory functions. The anterior head region has sensory tentacles. The mouth contains a file-like rasping organ for feeding, called radula.

Topic: Biology, Animal Kingdom, NEET
Which of the following character is unique to Tusk-shell?

Options:
A Water vascular system
B Head, muscular foot and visceral hump
C Radial symmetry
D Choanocytes

The correct answer is:
Head, muscular foot and visceral hump

Solution:
Phylum Mollusca:
This is the second largest animal phylum. Molluscs are terrestrial or aquatic (marine or freshwater) having an organ-system level of organisation. They are bilaterally symmetrical, triploblastic and coelomate animals. Body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot and visceral hump. A soft and spongy layer of skin forms a mantle over the visceral hump. The space between the hump and the mantle is called the mantle cavity in which feather-like gills are present. They have respiratory and excretory functions. The anterior head region has sensory tentacles. The mouth contains a file-like rasping organ for feeding, called radula.
Examples: Pila (Apple snail), Pinctada (Pearl oyster), Sepia (Cuttlefish), Loligo (Squid), Octopus (Devil fish), Aplysia (Seahare), Dentalium (Tusk shell) and Chaetopleura (Chiton).

Topic: Biology, Animal Kingdom, NEET
Which of the following characteristic features always holds true for the corresponding group of animals?

Options:
A Cartilaginous endoskeleton - Chondrichthyes
B Viviparous - All mammals
C Possess a mouth with an upper and a lower jaw - Chordata
D 3 – chambered heart with one incompletely divided ventricle - Reptilia

The correct answer is:
Cartilaginous endoskeleton - Chondrichthyes

Solution:
Reptillia has an order crocodilian which shows 4 chambered heart.

In mammals, prototheria group shows oviparity while metatheria and eutherian show viviparity.

Chordates can be gnathostomata (jawed organism) and agnatha (without jaws).

Only cartilaginous fishes (chondrichthyes) show cartilaginous endoskeleton without any exception.

Topic: Biology, Animal Kingdom, NEET, NEET 2016 (Phase 1)
Which of the following characteristics are found in a healthy cell?

A. Metastasis
B. Presence of contact inhibition
C. Presence of proto-oncogenes
D. Uncontrolled cell division

Options:
A B+C
B A+C
C B+C
D B+D

The correct answer is:
B+C

Solution:
Contact inhibition: This is a property of normal cells because of which contact with other cells keeps a check on their uncontrolled growth Cancer cells inactivate tumor suppressor genes and activate proto-oncogenes, so they form tumors.
Tissue invasion and metastasis: Cancer cells acquire the capacity to migrate to other organs, invade other tissues, and colonize these organs, resulting in their spread throughout the body.

Topic: Biology, Human Health and Diseases, NEET
Which of the following characteristics is incorrect with respect to cockroaches?

Options:
A A ring of gastric caeca is present at the junction of midgut and hindgut.
B Hypopharynx lies within the cavity enclosed by the mouth parts.
C In females, 7th -9th sterna together form a genital pouch.
D 10th abdominal segment in both sexes, bears a pair of anal cerci.

The correct answer is:
A ring of gastric caeca is present at the junction of midgut and hindgut.

Solution:
At the junction between foregut and midgut, 6-8 finger-like tubular structures are present called hepatic caeca or gastric caeca. These hepatic caeca help in the secretion of digestive enzymes and absorption.

Topic: Biology, Structural Organisation in Animals, NEET, NEET 2021