datavorous/entrance-exam-dataset huggingface dataset:
Which of the following statements are true for the phylum-Chordata?

(a) In Urochordata, notochord extends from head to tail, and it is present throughout their life.

(b) In Vertebrata, the notochord is present during the embryonic period only.

(c) Central nervous system is dorsal and hollow.

(d) Chordata is divided into 3 subphyla: Hemichordata, Tunicata, and Cephalochordata.

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

The correct answer is:
(b) and (c)

Solution:
Fundamental characters of phylum chordates:
1. Presence of notochord: They are characterized by the presence of rod-like supporting notochord extending throughout the length of the body.
2. Presence of dorsal tubular nerve cord: They are characterized by the presence of dorsal nerve cord lying above the notochord.
3. Presence of paired pharyngeal gill slits: They are characterized by the presence of paired pharyngeal gill slits at some stage of their lifetime.
4. Presences of ventral heart: They are characterized by a ventral heart, i.e. heart is situated on the ventral side of the alimentary canal in the body cavity.
5. Presence of post-anal tail.
6. Body cavity: They are coelomates, Triploblsatic body, and bilaterally symmetrical animals.

Phylum Chordata is divided into three sub-phyla:
1. Urochordata (Gr: aura-tail): Here, the notochord is confined only to the tall region of the larva. It is represented by primitive chordates like Ascidia, Herdmania, commonly called ‘sea squirt’.
2. Cephalochordate (Gr: cephalon-head): Here, the notochord is well-developed, extending from the anterior to the posterior region of the body. Anteriorly, it extends beyond the nerve cord. Hence, the name cephalochordate. It includes primitive chordates like Amphioxus. Since the above two subphyla include primitive chordates, they are also called Protochordata.
3. Vertebrata or Craniata: Here, the notochord is replaced by the vertebral column.

Topic: Biology, Animal Kingdom, NEET, NEET 2020 (Phase 1)
Which of the following statements is CORRECT?

Options:
A Spirullina is a biopesticide.
B Propionibacterium shermanii is involved in the formation of Swiss cheese.
C Germinating barley seeds are used in the preparation of Toddy.
D Secondary treatment of sewage involves the vigorous growth of anaerobic microbes into flocs.

The correct answer is:
Propionibacterium shermanii is involved in the formation of Swiss cheese.

Solution:
Swiss cheese has large holes in it due to carbon dioxide formation by the activity of bacteria Propionibacteriumsharmanii.
Spirulina is used as a source of single cell protein.
Secondary treatment of sewage involves the vigorous growth of aerobic microbes in to flocs.
‘Toddy’, a traditional drink of some parts of southern India is made by fermenting sap from palms.

Topic: Biology, Microbes in Human Welfare, NEET
Which of the following statements is correct?

a. rRNA is the most abundant RNA.
b. Ribosomes are composed of approximately 80% rRNA and 20% ribosomal proteins.
c. rRNA is a type of coding RNA.

Options:
A Statements 'a' 'b' and 'c' are correct
B Statement 'a' is correct
C Statements 'a' and 'c' are correct
D Statements 'b' and 'c' are correct

The correct answer is:
Statement 'a' is correct

Solution:
rRNA is most abundant in the cell. It constitutes 80% of the total RNA of the cell. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins. rRNA is a type of non-coding RNA.

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2017
Which of the following statements is correct?

a. rRNA is the most abundant RNA.
b. Ribosomes are composed of approximately 80% rRNA and 20% ribosomal proteins.
c. rRNA is a type of coding RNA.

Options:
A Statements 'a' 'b' and 'c' are correct
B Statement 'a' is correct
C Statements 'a' and 'c' are correct
D Statements 'b' and 'c' are correct

The correct answer is:
Statement 'a' is correct

Solution:
rRNA is most abundant in the cell. It constitutes 80% of the total RNA of the cell. Ribosomes are composed of approximately 60% rRNA and 40% ribosomal proteins. rRNA is a type of non-coding RNA.

Topic: Biology, Molecular Basis of Inheritance, NEET
Which of the following statements is CORRECT about a woody dicot stem which shows extensive secondary growth?

Options:
A The primary xylem persists in the centre of the axis.
B Primary and the older secondary phloem get crushed.
C Secondary xylem forms the bulk of the stem.
D All of these

The correct answer is:
All of these

Solution:
Secondary growth is responsible for thickening the stem and roots, making them woody. This growth is a result of cell division in the cambium. When a woody dicot stem undergoes secondary growth the primary xylem (formed from the procambium) persists inside the stem in the centre of the axis without being damaged or changed during the growth. The secondary xylem is found covering the primary xylem and keeps growing in girth forming the bulk of stem. Due to this growth of the xylem during the secondary growth, the primary phloem and the older secondary phloem they get crushed towards the epidermis and form the wood.

Topic: Biology, Anatomy of Flowering Plants, NEET
Which of the following statements is false?

Options:
A Kirchhoff's second law represents energy conservation
B Wheatstone bridge is the most sensitive when all the four resistances are of the same order of magnitude
C In a balanced Wheatstone bridge if the cell and the galvanometer are exchanged, the null point is disturbed
D A rheostat can be used as a potential divider

The correct answer is:
In a balanced Wheatstone bridge if the cell and the galvanometer are exchanged, the null point is disturbed

Solution:
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Topic: Physics, Current Electricity, NEET
Which of the following statements is INCORRECT?

Options:
A In the dicot root, the vascular cambium is completely secondary in origin.
B Wood is the common name used for secondary xylem.
C A mature sieve tube element lacks peripheral cytoplasm, a large vacuole and a prominent nucleus.
D Lenticels are the aerating pores present in the bark of plants and are associated with gaseous exchange.

The correct answer is:
A mature sieve tube element lacks peripheral cytoplasm, a large vacuole and a prominent nucleus.

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.

Topic: Biology, Anatomy of Flowering Plants, NEET
Which of the following statements is incorrect?

Options:
A In $\mathrm{K}_{4}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$ the ligand has satisfied both primary and secondary valencies of ferrous ion.
B In $\left[\mathrm{Cu}\left(\mathrm{NH}_{3}\right)_{4}\right] \mathrm{SO}_{4}$, the ligand has satisfied only the secondary valency of copper.
C In $\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$, the ligand has satisfied only the secondary valency of ferric ion.
D In $\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$, the ligand has satisfied both primary and secondary valencies of ferric ion.

The correct answer is:
In $\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$, the ligand has satisfied both primary and secondary valencies of ferric ion.

Solution:
In $\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]$, the ligand has satisfied both primary and secondary valencies of ferric ion. The $+3$ charge of ferric ion is satisfied by negative charge on cyanide ion. The coordination sphere's secondary valency is satisfied by six cyanide ligands.

Topic: Chemistry, Coordination Compounds, COMEDK, COMEDK 2016
Which of the following statements is incorrect about Leydig cells?

Options:
A They are abundant in early foetal life.
B They gradually diminish during childhood.
C Their numbers increase at puberty.
D They are absent in old age.

The correct answer is:
They are absent in old age.

Solution:
Leydig cells are present in old age as well.
Leydig cells, also known as interstitial cells of Leydig, are found adjacent to the seminiferous tubules in the testicle. They produce testosterone in the presence of the luteinizing hormone (LH).

Topic: Biology, Human Reproduction, NEET
Which of the following statements is not correct?

Options:
A Plant growth is generally determinate.
B Plant growth is measurable.
C Phase of cell elongation of plant cells is characterized by increased vacuolation.
D Cells in the meristematic phase of growth exhibit abundant plasmodesmatal connections.

The correct answer is:
Plant growth is generally determinate.

Solution:
Plant growth is generally indeterminate. Rest statements are correct.

Topic: Biology, Plant - Growth and Development, NEET, NEET 2023 (Manipur)
Which of the following statements is not correct for the relation $\mathrm{R}$ defined by aRb if and only if b lives within one kilometer from a?

Options:
A $\mathrm{R}$ is reflexive
B $\mathrm{R}$ is symmetric
C $\mathrm{R}$ is notanti-symmetric
D None of the above

The correct answer is:
$\mathrm{R}$ is symmetric

Solution:
aRb means bliveswith one $\mathrm{km}$ from $\mathrm{a}$, and bRa means a lives within one $\mathrm{km}$ from $\mathrm{b}$ but distance from $\mathrm{a}$ to $\mathrm{b}=$ distance from $\mathrm{b}$ to $\mathrm{a}$. So, R issymmetric.

Topic: Mathematics, Sets and Relations, NDA, NDA 2006 (Phase 1)
Which of the following statements is not correct regarding conservation laws?

Options:
A A conservation law is a hypothesis based on observations and experiments.
B Conservation laws do not have a deep connection with symmetries of nature.
C A conservation law cannot be proved.
D Conservation of energy, linear momentum, angular momentum are considered to be fundamental laws of Physics.

The correct answer is:
Conservation laws do not have a deep connection with symmetries of nature.

Solution:
The laws of conservation have a deep connection with symmetries of nature. This is first theorised by Noether. Noether's first theorem states that any differentiable symmetry of the action of a physical system has a corresponding conservation law. This means that conservation laws are observed because of the symmetries of nature.

Topic: Physics, Center of Mass Momentum and Collision, COMEDK, COMEDK 2014
Which of the following statements is not true about atomic mass?

Options:
A The atomic mass of an element is expressed relative to ${ }^{12} \mathrm{C}$ isotope of carbon.
B Atomic mass of $\mathrm{Na}$ is 23 .
C The atomic mass of an atom is obtained by taking sum of atomic masses of different isotopes of the element.
D Atomic mass used for an element is the average atomic mass obtained by taking into account the natural abundance of different isotopes of that element.

The correct answer is:
The atomic mass of an atom is obtained by taking sum of atomic masses of different isotopes of the element.

Solution:
Atomic mass is a weighted average of all the
isotopes of that element, in which the mass of each isotope is multiplied by the abundance of that particular isotope. It is also expressed relative to $\mathrm{C}^{12}$ isotope of carbon, also atomic mass of $\mathrm{Na}$ is 23 . Hence, option (c) not true and is the correct.

Topic: Chemistry, Structure of Atom, TS EAMCET, TS EAMCET 2020 (09 Sep Shift 2)
Which of the following statements is true about secondary amines in the carbylamine reaction?

Options:
A Secondary amines give a positive test.
B Secondary amines give a negative test.
C Secondary amines give a positive test only with strong bases.
D Secondary amines give a positive test only with strong acids.

The correct answer is:
Secondary amines give a negative test.

Solution:
Secondary amines do not give a positive carbylamine test; they give a negative result.

Topic: Chemistry, Amines, NEET
Which of the following statements is true about the carbylamine reaction for amines?

Options:
A Primary amines give a positive carbylamine test.
B Tertiary amines give a positive carbylamine test.
C Aromatic amines give a positive carbylamine test.
D Secondary amines give a positive carbylamine test.

The correct answer is:
Primary amines give a positive carbylamine test.

Solution:
Primary amines typically give a positive carbylamine test by forming foul-smelling isocyanides.

Topic: Chemistry, Amines, NEET
Which of the following statements is wrong –

Options:
A All methyl ketones give a positive iodoform test.
B Acetaldehyde is the only aldehyde that gives iodoform test.
C All secondary alcohols give positive iodoform test.
D Any alcohol that can be oxidised to an acetyl group gives a positive iodoform test.

The correct answer is:
All secondary alcohols give positive iodoform test.

Solution:
This compound which contain methyl ketonic linkage or which can change to methyl ketonic linkage can give a positive iodoform test. So, all secondary Alcohol can’t be given positive iodoform test therefore option (C) is correct.

Topic: Chemistry, Aldehydes and Ketones, NEET
Which of the following statements is/are correct in respect of regression coefficients?
1 . It measures the degree of linear relationship between Iwo variables
2 . It gives the value by which one variable changes for unit change in the other variable. Select the correct answer using the code given below

Options:
A 1 only
B 2 only
C Both Land
D Neither 1 nor

The correct answer is:
2 only

Solution:
It gives the value by which one variable changes for a unit change in the other variable. option (b) is correct.

Topic: Mathematics, Statistics, NDA, NDA 2015 (Phase 1)
Which of the following statement/s is/are not the characteristic feature of Kingdom Protista?

(a) They include chrysophytes, dinoflagellates, euglenoids, slime molds, and protozoans
(b) Chief producers in the ocean are diatoms.
(c) Toxins are released by some of the members of this kingdom.
(d) They are either unicellular or multicellular.

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

The correct answer is:
Only d

Solution:
All single-celled eukaryotes are placed under Protista, but the boundaries of this kingdom are not well-defined. What may be 'a photosynthetic protistan' to one biologist may be 'a plant' to others. Chrysophytes, dinoflagellates, euglenoids, slime moulds and protozoans are included under Protista. Members of Protista are primarily aquatic. Diatoms are chief producers of the ocean, and dinoflagellates are known to release some toxic substances.

Topic: Biology, Biological Classification, NEET
Which of the following statements regarding cilia is not correct?

Options:
A cilia contain an outer ring of nine doublet microtubules surrounding two single microtubules.
B the organized beating of cilia is controlled by fluxes of $\mathrm{Ca}^{2+}$ across the membrane
C cilia arc hair-like cellular appendages
D microtubules of cilia are composed of tubulin

The correct answer is:
the organized beating of cilia is controlled by fluxes of $\mathrm{Ca}^{2+}$ across the membrane

Solution:
Cilia are minute, hair-like processes on the surface of protozoans or on metazoan cells. Each cilium contains a peripheral circle of nine doubled microtubules arranged around two single microtubules. Each microtubule is composed of tubulin proteins. The mechanism of ciliary movement is not completely understood. The fluxes of $\mathrm{Ca}^{2+}$ across the membrane are not responsible for controlling the organised beating of cilia.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2006
Which of the following structure has the highest concentration of cone cells?

Options:
A Fovea centralis
B Blind spot
C Ciliary body
D Choroid

The correct answer is:
Fovea centralis

Solution:
A circular field of approximately 6 mm around the fovea is considered the central retina has abundance of cone cells.

Topic: Biology, Neural Control and Coordination, NEET
Which of the following structure is not made up of a single layer of flattened cell with irregular boundaries?

Options:
A Alveoli
B Endothelium
C Bowman's capsule
D Skin

The correct answer is:
Skin

Solution:
The type of epithelium which is made up of a single layer of flattened cells with irregular boundaries is known as squamous epithelium. It forms the endothelium of blood vessels and the lining of alveoli and Bowman's capsule. The type of epithelium which covers the dry surface of the skin is compound epithelium. It is made up of more than one layer of cells. It is protective in function.

Topic: Biology, Structural Organisation in Animals, NEET
Which of the following structure is not related to the life cycle of Funaria?

Options:
A Protonema
B Spore
C Prothallus
D Antheridia

The correct answer is:
Prothallus

Solution:
Funaria is a Bryophyte in which the spore germinates to form a filamentous branched creeping structure called protonema, which is the primary stage, from which develops a secondary stage on which sex organs antheridium and archegonium are formed. Prothallus is a gametophyte found in Pteridophytes.

Topic: Biology, Plant Kingdom, NEET
Which of the following structures are not supported by incomplete cartilaginous rings?

Options:
A Tertiary bronchi
B Initial bronchioles
C Terminal bronchioles
D Secondary bronchi

The correct answer is:
Terminal bronchioles

Solution:
Trachea is a straight tube extending up to the mid-thoracic cavity, which divides at the level of 5th thoracic vertebra into a right and left primary bronchi. Each bronchi undergoes repeated divisions to form the secondary and tertiary bronchi and bronchioles ending up in very thin terminal bronchioles. The tracheae, primary, secondary and tertiary bronchi, and initial bronchioles are supported by incomplete cartilaginous rings. Each terminal bronchiole gives rise to a number of very thin, irregular-walled and vascularised bag-like structures called alveoli.

Topic: Biology, Breathing and Exchange of Gases, NEET
Which of the following structures doesn't have cartilaginous rings?

Options:
A Primary bronchi
B Trachea
C Initial bronchioles
D Terminal bronchioles

The correct answer is:
Terminal bronchioles

Solution:
The trachea, primary, secondary and tertiary bronchi, and initial bronchioles are supported by incomplete cartilaginous rings. Within the lungs, the bronchi branch into smaller bronchi and even smaller tubes called bronchioles. Bronchioles end in tiny air sacs called alveoli, where the exchange of oxygen and carbon dioxide actually takes place. Each person has hundreds of millions of alveoli in their lungs.

Topic: Biology, Breathing and Exchange of Gases, NEET
Which of the following substances has highest value of standard molar enthalpy of formation at \(298 \mathrm{~K}\) ?

Options:
A \(\mathrm{NaF}(\mathrm{s})\)
B \(\mathrm{NaCl}(\mathrm{s})\)
C \(\mathrm{NaBr}(\mathrm{s})\)
D \(\mathrm{Nal}(\mathrm{s})\)

The correct answer is:
\(\mathrm{NaF}(\mathrm{s})\)

Solution:
Higher the stability of a substance, higher will be its standard molar enthalpy of formation value, \(\left|\Delta_f H^{\circ}\right|\)
Among the halides, \(\mathrm{F}^{-}\)is smallest and \(\mathrm{I}^{-}\)is largest in size. So, according to Fajan's rule, \(\mathrm{NaF}\) is mostly ionic in nature.
\(\mathrm{NaI} < \mathrm{NaBr} < \mathrm{NaCl} < \mathrm{NaF}\)
\(\longrightarrow\) Ionic nature
\(\longrightarrow\) Thermal stability
So, \(\mathrm{NaF}\) has highest value of \(\left|\Delta_f H^{\circ}\right|\).

Topic: Chemistry, Thermodynamics (C), AP EAMCET, AP EAMCET 2020 (17 Sep Shift 2)
Which of the following types of roots are correctly matched with their examples?

I. Apogeotropic roots: Rhizophora
II. Absence of calyptra: Lemna
III. Velamen containing roots: Vanda
IV. Moniliform roots: Portulaca

Options:
A I and II
B III and IV
C I, II and IV
D I, II, III and IV

The correct answer is:
I, II, III and IV

Solution:
Apogeotropic means negatively geotropic roots. They are seen in halophytes that grow in oxygen-deficient soil. So the root grows vertically upwards. They are also called pneumatophores. They are seen in Rhizophora, Sonneratia, Heritiera, etc. The Calyptra is a root cap. It is absent in hydrophytes that float on water such as Lemna, Pistia, etc. Velamen is hygroscopic roots found in epiphytes (plants which grow on large trees) such as Vanda. Moniliform roots are beaded roots found in Mimordica, Portulaca, etc.

Topic: Biology, Morphology of Flowering Plants, NEET
Which of the following types of vascular bundles are found in a monocot root?

Options:
A Collateral, conjoint and closed
B Radial vascular bundle with exarch xylem
C Bicollateral, conjoint and closed
D Radial vascular bundle with endarch xylem

The correct answer is:
Radial vascular bundle with exarch xylem

Solution:
In roots vascular bundles are radial in which xylem bundle alternates with phloem bundle and number of xylem bundle is equal to number of phloem bundle. Xylem is exarch in which protoxylem is present towards the periphery and metaxylem is present towards the center.

Topic: Biology, Anatomy of Flowering Plants, NEET
Which of the following uses maximum energy?

Options:
A Primary producer
B Primary consumers
C Secondary consumers
D Decomposer

The correct answer is:
Primary producer

Solution:
Primary producers are the autotrophs that produce energy, carbohydrates, through photosynthesis by capturing solar energy. Producers occupy the first trophic level having the greatest biomass or gross primary production (GPP). When energy gets transduced from producers to herbivores and to carnivores, only 10% of energy is transferred from one trophic level to another trophic level. Hence, producers receive the maximum energy.

Topic: Biology, Ecosystem, NEET
Which of the following waves of ECG are correctly paired with their events?

Options:
A P wave - depolarisation of atria
B QRS complex - Repolarisation of ventricles
C T wave- start of systole
D T wave - end of diastole

The correct answer is:
P wave - depolarisation of atria

Solution:
The graphical representation of the electrical activity of the heart is called the electrocardiogram (ECG). A standard ECG consists of different waves which correspond to specific electrical event in the heart. First is the P wave which represents the excitation of the atria also known as depolarization of the atria. It leads to contraction of atria. The next is the QRS complex which signifies the depolarization of the ventricles leading to ventricular contraction. T wave corresponds to ventricular repolarisation.

Topic: Biology, Body Fluids and Circulation, NEET
Which of the following will have the same ploidy level?

Options:
A Primary spermatocyte, primary oocyte, and second polar body
B Oogonia, primary oocyte, and first polar body
C Second polar body, spermatids, and primary spermatocyte
D First polar body, secondary oocyte, and spermatozoa

The correct answer is:
First polar body, secondary oocyte, and spermatozoa

Solution:
In human females, during oogenesis, the diploid structure with 46 chromosomes 44+XX is oogonium, which divides mitotically and gives rise to the primary oocyte (2n). Secondary oocyte, first and second polar body and ovum are produced as a result of meiotic division, and hence, they are haploid in nature.
In human males, during spermatogenesis, in the diploid structure with 46 chromosomes, 44+XY is spermatogonium, which grows in size and volume and produces to the primary spermatocyte (2n). Secondary spermatocyte, spermatids and spermatozoa are produced as a result of meiotic division and spermiogenesis; hence, they are haploid in nature.

Topic: Biology, Human Reproduction, NEET