datavorous/entrance-exam-dataset huggingface dataset:
Which of the following is an example of negative feedback loop in humans?

Options:
A secretion of tears after falling of sand particles into the eye
B salivation of mouth at the sight of delicious food
C secretion of sweat glands and constriction of skin blood vessels when it is too hot
D constriction of skin blood vessels and contraction of skeletal muscles when it is too cold.

The correct answer is:
constriction of skin blood vessels and contraction of skeletal muscles when it is too cold.

Solution:
When the set point of hypothalamus is disturbed by high temperature, it stimulates vasodilation and sweating while in low temperature there is vasoconstriction and shivering.
Related Theory
Feedback loops are used extensively to regulate secretion of hormones in the hypothalamic-pituitary axis. An important example of a negative feedback loop is seen in control of thyroid hormone secretion. The thyroid hormones thyroxine and triiodothyronine (" $T_4$ and $T_3$ ") are synthesized and secreted by thyroid glands and affect metabolism throughout the body.

Topic: Biology, Neural Control and Coordination, NEET, NEET 2007
Which of the following is an example of negative feedback loop in humans?

Options:
A Secretion of tears after falling of sand particles into the eye
B Salivation of mouth at the sight of delicious food
C Secretion of sweat glands and constriction of skin blood vessels when it is too hot
D Constriction of skin blood vessels and contraction of skeletal muscles when it is too cold

The correct answer is:
Constriction of skin blood vessels and contraction of skeletal muscles when it is too cold

Solution:
When the set point of hypothalamus is disturbed by high temperature, it stimulates vasodilation and sweating while in low temperature there is vasoconstriction and shivering.

Topic: Biology, Neural Control and Coordination, NEET
Which of the following is an example of negative feedback?

Options:
A Sucking reflex
B Uterine contractions during labor
C Secretion of CRH in response to ACTH
D Hair erection due to low body temperature

The correct answer is:
Secretion of CRH in response to ACTH

Solution:
CRH is also known as corticotropin releasing hormone. CRH is released by hypothalamus and stimulate anterior pituitary which release ACTH. ACTH stimulates adrenal cortex and release cortisol.
After increase in cortisol there is negative feedback created on hypothalamus to decrease cortisol.

Topic: Biology, Chemical Coordination and Integration, NEET
Which of the following is an example of nonpoint source pollution?

Options:
A Industrial discharge
B Agricultural runoff
C Municipal sewage
D Acid rain

The correct answer is:
Agricultural runoff

Solution:
Agricultural runoff, which includes pollutants from farms, animals, and croplands, is an example of nonpoint source pollution because it cannot be easily traced to a specific source.

Topic: Chemistry, Environmental Chemistry, NEET
Which of the following is an example of nucleophilic addition?

Options:
A
B
C Both and
D None of the two

The correct answer is:
Both and

Solution:
In the reduction of carbonyl group with LiAlH4 or NaBH4, a hydride ion is transferred from the metal to the carbonyl carbon (nucleophilic addition).

Topic: Chemistry, Aldehydes and Ketones, NEET
Which of the following is an example of organic dye?

Options:
A Methylene red
B Methylene blue
C Crystal violet
D Malachite green

The correct answer is:
Methylene blue

Solution:
Methylene blue is an example of an organic dye.

Topic: Chemistry, Surface Chemistry, NEET
Which of the following is an example of progressive degeneration disease?

Options:
A Muscular dystrophy
B Alzheimer's disease
C Cystic fibrosis
D All of these

The correct answer is:
All of these

Solution:
The muscular dystrophies (MD) are a group of inherited genetic conditions that gradually cause the muscles to weaken, leading to an increasing level of disability. MD is a progressive condition, which means it gets worse over time. Alzheimer's disease is a progressive degenerative disorder that causes brain cells to waste away (degenerate), leading to dementia. Cystic fibrosis is also a hereditary progressive degenerative disorder that affects the lungs and digestive system. Thick and sticky mucus is produced that clogs the lungs, obstructing the pancreas.

Topic: Biology, Locomotion and Movement, NEET
Which of the following is an example of saprophytes?

Options:
A Agaricus
B Lichen
C Chlamydomonas
D Ferns

The correct answer is:
Agaricus

Solution:
Mushroom (Agaricus) is a basidiomycetes fungus, which grows on dead and decaying matter.

Topic: Biology, Biological Classification, NEET
Which of the following is an example of sex-linked disease?

Options:
A AIDS
B Colour-blindness
C Syphillis
D Gonorrhoea

The correct answer is:
Colour-blindness

Solution:
AIDS is a viral disease which can be transmitted through sexual intercourse. Syphilis and gonorrhoea are both sexually transmitted diseases. Colour-blindness is a sex linked disease.

Topic: Biology, Principles of Inheritance and Variation, NEET
Which of the following is an example of stem and leaf tendril, respectively?

Options:
A Peas and cucumber
B Cucumber and peas
C Peas and pumpkin
D Hibiscus and cucumber

The correct answer is:
Cucumber and peas

Solution:
Stem tendrils that develop from axillary buds are slender and spirally coiled and help plants to climb, e.g., in gourds (cucumber, pumpkins, watermelon) and grapevines. Leaves are converted into tendrils for climbing, as in peas, or into spines for defence, as in cacti.

Topic: Biology, Morphology of Flowering Plants, NEET
Which of the following is an example of step-growth polymer?

Options:
A Polyisoprene
B Polythene
C Nylon
D Polyacrylonitrile

The correct answer is:
Nylon

Solution:
Step growth polymerization involves condensation reaction between two difunctional monomer to produce dimer which in turn, produce, tetramer and so on with the loss of simple molecules like H2O,NH3,HCl etc.

Topic: Chemistry, Polymers, NEET
Which of the following is an example of the type of placentation given below?

Options:
A Dianthus and Primrose
B Sunflower and Marigold
C Tomato and Lemon
D Argemone and Mustard

The correct answer is:
Dianthus and Primrose

Solution:
The placentation is arrangement of ovules in the ovary. The diagram shows free central placentation. In this kind of placentation, the ovules are borne on central axis and septa are absent. The example of flowers showing free central placentation are Dianthus and primrose.

Topic: Biology, Morphology of Flowering Plants, NEET
Which of the following is an example of thermosetting polymers?

Options:
A Bakelite
B PVC
C Nylon 6, 6
D Buna-S

The correct answer is:
Bakelite

Solution:
Bakeliteor 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.

Topic: Chemistry, Polymers, NEET
Which of the following is an example of true fruit?

Options:
A

Strawberry

B

Apple

C

Pea

D

Pear

The correct answer is:

Pea

Solution:
True fruit: A fruit that is derived from only the ovary and its contents, usually derived from a superior (inserted above the other floral parts) ovary, e.g., pea.

False fruit: A fruit derived from the ovary and its contents as well as other parts of the flower it is usually derived from an inferior (inserted below other floral parts) ovary, e.g., apple (modified thalamus), pear, and strawberry (modified receptacle).

Topic: Biology, Morphology of Flowering Plants, NEET
Which of the following is an important alloy which contains some of the lanthanoid metals?

Options:
A Stainless Steel
B Bronze
C Copper
D Mischmetall

The correct answer is:
Mischmetall

Solution:
Correct Option is : (D)
Mischmetall

Topic: Chemistry, d and f Block Elements, NEET
Which of the following is an incorrect match?

Options:
A First product in C3 cycle: 3-Phosphoglyceric acid
B Ribulose - 1,5 - biphosphate (RuBP): 5 carbon aldose sugar
C Kranz anatomy in leaves: C4 plants
D Non-cyclic photophosphorylation: Grana.

The correct answer is:
Ribulose - 1,5 - biphosphate (RuBP): 5 carbon aldose sugar

Solution:
Ribulose-1,5-biphosphate (RuBP) is 5 carbon ketose sugar.

Topic: Biology, Photosynthesis in Higher Plants, NEET
Which of the following is an incorrect statement?

Options:
A Brown algae has chlorophyll a and c, and fucoxanthin
B Archegonia are found in Bryophyta, pteridophyta and gymnosperm.
C The red algae usually reproduces vegetatively by fragmentation
D Fusion of two gametes of similar size takes place as in species of Eudorina.

The correct answer is:
Fusion of two gametes of similar size takes place as in species of Eudorina.

Solution:
Sexual reproduction takes place through fusion of two gametes. These gametes can be flagellated and similar in size (as in Ulothrix) or non-flagellated (non-motile) but similar in size (as in Spirogyra). Such reproduction is called isogamous. Fusion of two gametes dissimilar in size, as in species of Eudorina is termed as anisogamous. Fusion between one large, nonmotile (static) female gamete and a smaller, motile male gamete is termed oogamous, e.g., Volvox, Fucus.

Topic: Biology, Plant Kingdom, NEET
Which of the following is an incorrect statement?

Options:
A Fluorine is highly reactive
B HF molecules form intermolecular H-bonds
C Halogens show only (-I) oxidation state
D Halogens are strong oxidizing agent

The correct answer is:
Halogens show only (-I) oxidation state

Solution:
Fluorine, being most electronegative element, always shows the oxidation state of -1.
Other halogens can show higher positive oxidation states in addition to negative oxidation of -1 with more electronegative atoms like F, O, N. Rest other statements are correct.

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET
Which of the following is an incorrect statement?

Options:
A Chemically, adenine is 6 amino purine
B Cytosine and adenine are purine bases.
C Two DNA strands are antiparallel due to hydrogen bonds holding them together
D Pitch of dsDNA is 3.4 nm

The correct answer is:
Cytosine and adenine are purine bases.

Solution:
DNA structure contains four types of bases - adenine, guanine, thymine and cytosine.
Adenine and guanine are types of purines whereas cytosine and thymine are types of pyrimidines.

Topic: Biology, Molecular Basis of Inheritance, NEET
Which of the following is an incorrect statement?

Options:
A Mature sieve tube elements possess a conspicuous nucleus and usual cytoplasmic organelles.
B Microbodies are present both in plant and animal cells.
C The perinuclear space forms a barrier between the materials present inside the nucleus and that of the cytoplasm.
D Nuclear pores act as passages for proteins and RNA molecules in both directions between nucleus and cytoplasm.

The correct answer is:
Mature sieve tube elements possess a conspicuous nucleus and usual cytoplasmic organelles.

Solution:
A mature sieve element possesses a peripheral cytoplasm and a large vacuole but lacks a nucleus. The functions of sieve tubes are controlled by the nucleus of companion cells. The companion cells are specialised parenchymatous cells, which are closely associated with sieve tube elements.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2021
Which of the following is an incorrect statement about ribose?

Options:
A It is a polyhydroxy compound
B It is an aldose sugar
C It has six carbon atoms
D It exhibits optical activity

The correct answer is:
It has six carbon atoms

Solution:
Ribose is a pentose sugar, it is polyhydroxy aldose.

Topic: Chemistry, Biomolecules, NEET
Which of the following is an incorrect statement regarding benign tumours?

Options:
A They do not grow back once they are removed.
B They do not metastasize.
C These cells grow very rapidly.
D They cause little damage.

The correct answer is:
These cells grow very rapidly.

Solution:
Benign tumours generally have a slower growth rate than malignant tumours and the tumour cells are usually more differentiated.

Topic: Biology, Human Health and Diseases, NEET
Which of the following is an incorrect statement regarding Plasmodium falciparum?

Options:
A It causes malignant malaria
B It is transmitted by mosquito
C It is a helminth
D It may be fatal

The correct answer is:
It is a helminth

Solution:
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 is an incorrect statement?

Options:
A Brown algae has chlorophyll a and c, and fucoxanthin
B In green algae, the cell wall is made up of cellulose.
C The red algae usually reproduces vegetatively by fragmentation
D The food is stored as laminarin in red algae

The correct answer is:
The food is stored as laminarin in red algae

Solution:
Red algae store food in the form of the floridean starch. Red algae lack any specialized asexual spores; thus, they usually reproduce by fragmentation. Brown algae store food in the form of mannitol and laminarin.

Topic: Biology, Plant Kingdom, NEET
Which of the following is an innovative remedy for plastic waste?

Options:
A Burning in the absence of oxygen
B Burrying $500 \mathrm{~m}$ deep below soil surface
C Polyblend
D Electrostatic precipitator

The correct answer is:
Polyblend

Solution:
Polyblend is an innovative remedy for plastic waste. Polyblend is a fine powder of recycled modified plastic which when mixed with bitumen, can be used to lay roads.

Topic: Biology, Environmental Issues, NEET, NEET 2019 (Odisha)
Which of the following is an insulator and has a high melting point?

Options:
A SO2
B H2O
C AlN
D Ar

The correct answer is:
AlN

Solution:
Correct Option is : 3
AlN

Topic: Chemistry, Solid State, NEET
Which of the following is an intensive property of the system?

Options:
A Density
B Volume
C Total heat capacity
D Mass

The correct answer is:
Density

Solution:
Intensive properties are those that depend upon the nature of the substance.
The ratio of two extensive properties is an intensive property.

Topic: Chemistry, Thermodynamics (C), NEET
Which of the following is an isogamous plant, producing non-flagellated gametes?

Options:
A Spirogyra
B Volvox
C Chlamydomonas
D Fucus

The correct answer is:
Spirogyra

Solution:
Sexual reproduction takes place through fusion of two gametes. These gametes can be flagellated and similar in size (as in Chlamydomonas) or non-flagellated (non-motile) but similar in size (as in Spirogyra). Such reproduction is called isogamous. Fusion of two gametes dissimilar in size, as in some species of Chlamydomonas is termed as anisogamous. Fusion between one large, non-motile (static) female gamete and a smaller, motile male gamete is termed oogamous, e.g., Volvox, Fucus.

Topic: Biology, Plant Kingdom, NEET
Which of the following is an occupational respiratory disorder?

Options:
A Botulism
B Silicosis
C Anthrax
D Emphysema

The correct answer is:
Silicosis

Solution:
Silicosis is an occupational respiratory disorder that is caused due to excessive inhalation of silica dust. It usually affects the workers of grinding or stone-breaking industries. Long-term exposure can cause lung fibrosis (or stiffening), leading to breathing difficulties.

Topic: Biology, Breathing and Exchange of Gases, NEET, NEET 2018
Which of the following is an oxide ore?

Options:
A Copper pyrites
B Malachite
C Cuprite
D Copper glance

The correct answer is:
Cuprite

Solution:
Correct Option is : 3
Cuprite

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET
Which of the following is an oximeter anion of the first series of transition metals in which the metal exhibits the oxidation state equal to its group number?

Options:
A VO43-
B Cr2O7-
C CrO4-
D [MnO4]-

The correct answer is:
[MnO4]-

Solution:
Correct Option is : (D)
[MnO4]-

Topic: Chemistry, d and f Block Elements, NEET
Which of the following is appropriate for mass-flow hypothesis?

Options:
A Transpiration pull is responsible for absorption of ions
B Large amount of ions are also absorbed along with the absorption of water
C As suction pressure increases, absorption of water increases and along with water, absorption of ion also increases
D All of the above

The correct answer is:
All of the above

Solution:
According to mass-flow hypothesis, there is a mass flow of mineral ions into the root along with transpiration current. Actually, transpiration creates a suction pressure or transpiration pull, conveyed from leaf xylem to root hair, which causes absorption of water from the soil passively. A large amount of ions are also absorbed along with the absorption of water. When the rate of transpiration is high, absorption of water increases due to increased suction pressure and along with water, absorption of ions also increases.

Topic: Biology, Transport in Plants, NEET
Which of the following is /are true with reference to taxonomical aids?

a. Separate taxonomic keys are required for each taxonomic category.
b. Keys are not considered to be analytical in nature.
c. Each statement in the key is called a couplet.
d. Keys are used for identification purposes.

Options:
A a and b
B a and d
C a and c
D c and d

The correct answer is:
a and d

Solution:
Key is a taxonomical aid used for identification of plants and animals based on the similarities and dissimilarities. The keys are based on the contrasting characters generally in a pair called couplet. It represents the choice made between two opposite options. This results in acceptance of only one and rejection of the other. Each statement in the key is called a lead. Separate taxonomic keys are required for each taxonomic category such as family, genus and species for = identification purposes. Keys are generally analytical in nature.

Topic: Biology, The Living World, NEET
Which of the following is associated with Alfred Sturtevant?

Options:
A Genetic map
B Incomplete dominance
C Linkage
D Mutation

The correct answer is:
Genetic map

Solution:
Morgan's student Alfred Sturtevant used the frequency of recombination between gene pairs on the same chromosome as a measure of the distance between genes and 'mapped' their position on the chromosome. Today genetic maps are extensively used as a starting point in the sequencing of whole genomes as was done in the case of the Human Genome Sequencing Project.

Topic: Biology, Principles of Inheritance and Variation, NEET
Which of the following is associated with decrease in cardiac output?

Options:
A Sympathetic nerves
B Parasympathetic neural signals
C Pneumotaxic centre
D Adrenal medullary hormones

The correct answer is:
Parasympathetic neural signals

Solution:
The sympathetic nerve ending releases noradrenaline which stimulates the SAN that accelerates the heartbeat, the strength of ventricular contraction and thereby the cardiac output.

The parasympathetic nerve ending releases acetylcholine which decreases the rate of heartbeat, speed of conduction of action potential and thereby the cardiac output.

The adrenal medulla of the adrenal gland secretes two hormones called adrenaline and noradrenaline. Both the hormones are rapidly secreted in response to the stress of any kind and during emergency situations. These hormones increase the heartbeat and strength of heart contraction. Thus, adrenal medullary hormones can also increase cardiac output.

The pneumotaxic centre increases the rate of pulmonary ventilation, which in turn increases heartbeat and thus cardiac output.

Topic: Biology, Body Fluids and Circulation, NEET, NEET 2020 (Phase 2)
Which of the following is called Marsh gas?

Options:
A C2H4
B C2H6
C C2H2
D CH4

The correct answer is:
CH4

Solution:
Methane is called marsh gas because it is found in swamps or marshy places and can be obtained by bacterial decomposition of fossils of plants and animals.

Topic: Chemistry, Hydrocarbons, NEET
Which of the following is called the fret membrane?

Options:
A Thylakoids
B Quantasomes
C Stroma lamellae
D Grana

The correct answer is:
Stroma lamellae

Solution:
This membrane is found in the chloroplast. This organelle is present within plants and algae to carry out photosynthesis. They have a double-layered membrane that encloses a matrix called the stroma. In the stroma, a membrane-bound structure is present i.e .thylakoid which arranges as a stack to form granum. Grana connects to each other through stroma lamellae. It is also known as intergranal lamellae or fret lamellae. Space which is present in stroma lamellae is called fret channels and they have enzymes for carbon dioxide fixation.

Topic: Biology, Cell - The Unit of Life, NEET
Which of the following is called white vitriol?

Options:
A ZnCl2
B MgSO4.7H2O
C ZnSO4.7H2O
D Al2(SO4)3

The correct answer is:
ZnSO4.7H2O

Solution:
Zinc sulphate (ZnSO4.7H2O) is called white vitriol. It, when heated with barium sulphide, it forms a white pigment lithopone (ZnS+BaSO4) .

Topic: Chemistry, d and f Block Elements, NEET
Which of the following is called Wilkinson's catalyst?

Options:
A [RhCl(PPh3)3]
B TiCl4 + (C2H5)3Al
C (C2H5)4Pb
D [PtCl2(NH3)2]

The correct answer is:
[RhCl(PPh3)3]

Solution:
Wilkinson's catalyst is [RhCl(PPh3)3], Red-violet in colour and has square planar structure. It is used for selective hydrogenation of organic molecules at room temperature and pressure.
TiCl4 + (C2H5)3 Al is Zeigler Natta catalyst.
(C2H5)4)Pb is an anti-knocking agent.
cis-platin is used as anti-cancer agent]

Topic: Chemistry, d and f Block Elements, NEET
Which of the following is characteristic of phylum Ctenophora?

Options:
A Diploblastic with tissue grade body organization
B Only sexual method of reproduction but organisms are hermaphrodites
C The body bears eight external rows of ciliated comb plates and shows bioluminescence
D All of these

The correct answer is:
All of these

Solution:
Ctenophores, commonly known as sea walnuts or comb jellies, are exclusively marine, radially symmetrical, diploblastic organisms with tissue level of organization. The body bears eight external rows of ciliated comb plates, which help in locomotion. Digestion is both extracellular and intracellular. Bioluminescence (the property of a living organism to emit light) is well-marked in ctenophores. Sexes are not separate. Reproduction takes place only by sexual means. Fertilization is external with indirect development.
Examples: Pleurobrachia and Ctenoplana.

Topic: Biology, Animal Kingdom, NEET
Which of the following is characteristics feature of cockroach regarding sexual dimorphism?

Options:
A Presence of anal cerci
B Dark brown body colour and anal cerci
C Presence of anal styles
D Presence of selerites

The correct answer is:
Presence of anal styles

Solution:
Cockroaches are dioecious and both sexes have well-developed reproductive organs. The male and female cockroaches can be easily distinguished based on the presence or absence of anal styles.

Males bear a pair of short, threadlike anal styles which are absent in females. In both sexes, the 10th segment bears a pair of jointed filamentous structures called anal cerci.

Topic: Biology, Structural Organisation in Animals, NEET, NEET 2023 (All India)
Which of the following is characterized by presence of multicellular mobile colony?

Options:
A Chara
B Laminaria
C Volvox
D Dictyota

The correct answer is:
Volvox

Solution:
Volvox is multicellular mobile green algae. Each cell of Volvox is similar to Chlamydomonas.

Topic: Biology, Plant Kingdom, NEET
Which of the following is chiral?

Options:
A Alanine
B Valine
C Leucine
D Isoleucine

The correct answer is:
Isoleucine

Solution:
Correct Option is : 4
Isoleucine

Topic: Chemistry, Biomolecules, NEET
Which of the following is chloroform?

Options:
A CH3Cl
B CH2Cl2
C CCl4
D ChCl3

The correct answer is:
ChCl3

Solution:
Correct Option is : 4
ChCl3

Topic: Chemistry, Haloalkanes and Haloarenes, NEET
Which of the following is chlorous acid?

Options:
A HOCl
B HOClO
C HOClO2
D HOClO3

The correct answer is:
HOClO

Solution:
Correct Option is : 2
HOClO

Topic: Chemistry, p Block Elements (Group 15, 16, 17 & 18), NEET