datavorous/entrance-exam-dataset huggingface dataset:
Which one of the following condition in humans is correctly matched with its chromosomal abnormality/linkage?

Options:
A Klinefelter's syndrome-44 autosomes $+\mathrm{XXY}$
B Colourblindness - Y-linked
C Erythroblastosis foetalis-X-linked
D Down syndrome-44 autosomes + XO

The correct answer is:
Klinefelter's syndrome-44 autosomes $+\mathrm{XXY}$

Solution:
Klinefelter's syndrome is represented by 44 autosomes + XXY. When an abnormal egg with $\mathrm{XX}$ chromosome is fertilized by a sperm carrying Y-chromosome a zygote having $\mathrm{XXY}$ sex chromosomes is formed. The resulting young one is an abnormal sterile male.
The 44 autosome + XO condition is due to Turner's syndrome. Such females are sterile and have short stature, webbed neck, broad shield-shaped chest etc.
Down's syndrome is due to trisomy of $21^{\text {st }}$ pair of chromosome. It is characterised by moderate mental retardation, large tongue, short stature, stubby fingers, an enlarged liver and spleen.
Colourblindness is an X-linked disease. The person suffering from this disease cannot differentiate between red and green colours.
Erythrobalstosis-foetalis is caused due to $\mathrm{Rh}$ factor in child of $\mathrm{Rh}^{+}$man and $\mathrm{Rh}^{-}$woman.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2008 (Screening)
Which one of the following conditions correctly describes the manner of determining the sex in the given example?

Options:
A XO type of sex chromosomes determine male sex in grasshopper
B XO condition in humans as found in Turner syndrome, determines female sex
C Homozygous sex chromosomes (XX) produce male in Drosophila
D Homozygous sex chromosomes determine female sex in birds

The correct answer is:
XO type of sex chromosomes determine male sex in grasshopper

Solution:
Grasshopper is an example of XO type of sex determination in which the males have only one $\mathrm{X}$-chromosome besides the autosomes, whereas females have a pair of X-chromosomes.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2011 (Screening)
Which one of the following conditions correctly describes the manner of determining the sex in the given example?

Options:
A Homozygous sex chromosomes (ZZ) determine female sex in birds
B XO type of sex chromosomes determine male sex in grasshopper
C XO condition in human as found in Turner syndrome, determiners female sex
D Homozygous sex chromosomes (XX) produce male in Drosophila

The correct answer is:
XO type of sex chromosomes determine male sex in grasshopper

Solution:
In grasshopper, the males lack a Y-sex chromosome and have only an X-chromosome. They produce sperm cells that contain either an X-chromosome or no sex chromosome, which is designated as O.

Topic: Biology, Principles of Inheritance and Variation, NEET
Which one of the following conditions correctly describes the sex determination mechanism?

Options:
A Homozygous sex chromosomes (ZZ) determine female sex in birds.
B XO type of sex chromosomes determine male sex in grasshopper.
C XXY condition in humans as found in Turner's syndrome, determines female sex.
D Homozygous sex chromosomes (XX) produce male in Drosophila.

The correct answer is:
XO type of sex chromosomes determine male sex in grasshopper.

Solution:
XO type of sex chromosomes determine male sex in grasshoppers. Its common examples are cockroaches, grasshoppers and bugs. The female has two homomorphic sex chromosomes XX and is homogametic. It produces similar eggs, each with X chromosome. The male has one X chromosome only and is heterogametic.

Topic: Biology, Principles of Inheritance and Variation, NEET
Which one of the following conditions in humans is correctly matched with its chromosomal abnormality?

Options:
A Sickle cell anaemia - X linked
B Down's syndrome - 44 autosomes + XO
C Klinefelter's syndrome - 44 autosomes + XXY
D Colour blindness - Y linked

The correct answer is:
Klinefelter's syndrome - 44 autosomes + XXY

Solution:
Klinefelter's syndrome is a genetic disorder in which there are three sex chromosomes, XXY, rather than the normal XX or XY. The number of autosomes are normal i.e., 44. Affected individuals are apparently male but are tall and thin, with small testes, failure of normal sperm production (azoospermia), enlargement of the breasts (gynaecomastia) and absence of facial and body hairs.

Topic: Biology, Principles of Inheritance and Variation, NEET
Which one of the following conditions indicates Klinefelter's syndrome?

Options:
A 44 + XXY
B 44 + XO
C 44 + XY
D 44 + XX

The correct answer is:
44 + XXY

Solution:
Sex determining mechanism in human is of XY type. Out of 23 pairs of chromosome present, 22 pairs are exactly same in male and females, these are called as autosomes. Two X chromosomes are present in the females, whereas the presence of an X and Y chromosome are determinants of male characteristics.
44 + XO - Turner's syndrome, 44 + XY - Normal human male, 44 + XX - Normal human female

Topic: Biology, Principles of Inheritance and Variation, NEET
Which one of the following conditions will favor the maximum formation of the product in the reaction?
A2 g+B2 g⇌X2 g ΔrH=-X kJ

Options:
A High temperature and high pressure.
B Low temperature and low pressure.
C Low temperature and high pressure.
D High temperature and low pressure.

The correct answer is:
Low temperature and high pressure.

Solution:
logk2k1=ΔH2.303K(1T1−1T2)
∴ΔH=−ve and for the maximum formation of the product k2>k1 hence, T1>T2 mean temperature should decrease
Δng=−ve
kp∝1p on increasing p reaction goes in forward direction.

Topic: Chemistry, Chemical Equilibrium, NEET, NEET 2018
Which one of the following conditions will favour maximum formation of the product in the reaction, A 2 (q)+ B 2 (q)â X 2 (g) âputâ ; Î r H=âXâkJ?

Options:
A High temperature and high pressure
B Low temperature and low pressure
C Low temperature and high pressure
D High temperature and low pressure

The correct answer is:
Low temperature and high pressure

Solution:
Using Le-chatlier Principle
A2(g)+B2(g)⇌X2(g)ΔH=-X KJ
On increasing pressure, equilibrium shifts in a direction where volume or number of gaseous moles decreases, i.e., in forward direction here.
On decreasing temperature, equilibrium shifts in exothermic direction, i.e., forward direction as heat is coming out of system so decrease of temperature is needed.
Hence, high pressure and low temperature favours maximum formation of product in it.

Topic: Chemistry, Chemical Equilibrium, NEET
Which one of the following constitutes a group of the isoelectronic species?

Options:
A C22-, O2-, CO.NO
B CN-,Â N2,Â O22-,Â C22-
C NO+, C22-, CN-, N2
D N2,Â O2-,Â NO+,Â CO

The correct answer is:
NO+, C22-, CN-, N2

Solution:
Species having the same number of electrons called as isoelectronic species. By calculating the number of electrons in each species given here, we get
CN-6+7+1=14;N27+7=14;
O22-8+8+2=18;C22-6+6+2=14;
O2-8+8+1=17 ;NO+7+8-1=14
CO6+8=14;NO7+8=15
From the above calculation we find that all the species listed in choice c have 14 electrons each so it is the correct answer.

Topic: Chemistry, Structure of Atom, NEET
Which one of the following contains the largest quantity of extracellular material ?

Options:
A striated muscle
B areolar tissue
C stratified epithelium
D myelinated nerve fibres

The correct answer is:
areolar tissue

Solution:
Loose connective tissue, also called areolar connective tissue, is the packing materal of the body that anchors blood vessels, nerves and body organs. It contains largest quantity of extracellular material like fibres and ground substances which help to provide structural support to neighbouring cells, fibroblasts that synthesise the fibres and ground substance of connective tissue and wandering macrophages that phagocytise pathogens or damaged cells.

Topic: Biology, Structural Organisation in Animals, NEET, NEET 2003
Which one of the following conversions involve change in both hybridisation and shape?

Options:
A CH4⟶C2H6
B NH3⟶NH4+
C BF3⟶BF4-
D H2O⟶H3O+

The correct answer is:
BF3⟶BF4-

Solution:
(a) CH 4 â CH 3 - CH 3 4 bp + 0 lp 4 bp 4 bp Hybridisation sp 3 sp 3 sp 3 Structure Tetrahedral Tetrahedral Tetrahedral
(b) NH 3 â NH 4 + 3 bp + 1 lp 4 bp Hybridisation sp 3 sp 3
Structure pyramidal tetrahedral
(c) BF 3 â BF 4 - 3 bp 4 bp Hybridisation sp 2 sp 3 Structure trigonal tetrahedral planar
(d) H 2 O â H 3 O + 2 bp + 2 lp 3 bp + 1 lp Hybridisation sp 3 sp 3 Structure angular Pyramidal
Thus conversion of BF3 into BF4- involves change in both hybridisation and shape.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Which one of the following correctly describes the location of some body parts in the earthworm pheretima?

Options:
A Two pairs of accessory glands in 16-18 segments
B Four pairs of spermathecae in 4-7 segments
C One pair of ovaries attached at intersegmental septum of $14^{\text {th }}$ and $15^{\text {th }}$ segments
D Two pairs of testes in $10^{\text {th }}$ and $11^{\text {th }}$ segments

The correct answer is:
Two pairs of testes in $10^{\text {th }}$ and $11^{\text {th }}$ segments

Solution:
In earthworm, two pairs of testes are found in $10^{\text {th }}$ and $11^{\text {th }}$ segments, accessory glands in $17^{\text {th }}$ and $19^{\text {th }}$ segments, four pairs of spermatheca from $6^{\text {th }}-9^{\text {th }}$ segment and one pair of ovarises in $13^{\text {th }}$ segment.

Topic: Biology, Structural Organisation in Animals, NEET, NEET 2009 (Screening)
Which one of the following correctly explains the function of a specific part of a human nephron?

Options:
A Henle's loop $\quad$ - most reabsoroption of the major substances from the glomerular filtrate
B Distal convoluted reabsorption of ions into tubule the surronding blood capillaries
C Afferent arteriole carries the blood away from the glomerulus towards renal vein
D Podocytes - create minute spaces (slit pores) for the filtration of blood into the Bowman's capsule

The correct answer is:
Podocytes - create minute spaces (slit pores) for the filtration of blood into the Bowman's capsule

Solution:
Podocytes or visceral epithelial cells are the cells in Bowman's capsule in the kidneys that wrap around the capillaries of glomerules. They create minute pores (slit pores) for the filtration blood into the Bowman's capsule.

Topic: Biology, Excretory Products and their Elimination, NEET, NEET 2011 (Screening)
Which one of the following crosses shows the phenotypic ratio of 3:1?

Options:
A AaBb×AaBb
B aabb×AABb
C Aabb×Aabb
D AaBb×aabb

The correct answer is:
Aabb×Aabb

Solution:
When parents of genotype Aabb is crossed with Aabb we get the following progenies.

Ab	ab

Ab	AAbb	Aabb

ab	Aabb	aabb

Phenotypic ratio will be 3:1
Genotypic ratio will be 1:2:1

Topic: Biology, Principles of Inheritance and Variation, NEET
Which one of the following cyano complexes would exhibit the lowest value of paramagnetic behaviour?

(Atomic no. Cr=24, Mn=25, Fe=26, Co=27)

Options:
A CoCN63-
B FeCN63-
C MnCN63-
D CrCN63-

The correct answer is:
CoCN63-

Solution:
Hybridization	Unpaired
electrons	Magnetic
moment

CoCN63-	d2sp3	0	0

FeCN63-	d2sp3	1	3 BM

MnCN63-	d2sp3	2	8 BM

CrCN63-	d2sp3	3	15 BM

Topic: Chemistry, Coordination Compounds, NEET
Which one of the following depresses brain activity and produces feelings of calmness, relaxation and drowsiness?

Options:
A morphine
B valium
C amphetamines
D hashish

The correct answer is:
valium

Solution:
Valium depresses brain activity and produces feeling of calmness, relaxation and drowsiness. Morphine is an anaesthetic. Hashish is a cannabinoid, causes euphoria Amphetamine is a stimulant.
Related Theory
Diazepam is also known by its brand name, Valium. It is a benzodiazepine that is FDA approved to treat anxiety, alcohol withdrawal syndrome, and muscle spasms.

Topic: Biology, Human Health and Diseases, NEET, NEET 2005
Which one of the following diagrams represents the placentation in Dianthus?

Options:
A
B
C
D

The correct answer is:

Solution:
Placentation is the arrangement of the ovules in the ovary and their attachment to it. Placentation are of various type in the angiosperms - marginal, axile, central, parietal, basal, and free central.
Dianthus and Primrose display free-central placentation and in it the ovules are attached at the central axis of the ovary without any septa present like in axile pattern.
In marginal placentation, ovules are attached to the ridge formed on the ventral suture of the ovary. Pea plant has this arrangement. In parietal, the ovules are attached to the inner wall or towards the periphery of the ovary, observed in mustard plant and even Argemone and poppy. Sunflower and marigold show basal placentation where the ovules are attached at the base of the ovary.

Topic: Biology, Morphology of Flowering Plants, NEET
Which one of the following discoveries resulted in a Nobel Prize?

Options:
A X-rays induce sex-linked recessive lethal mutations
B cytoplasmic inheritance
C recombination of linked genes
D genetic engineering

The correct answer is:
X-rays induce sex-linked recessive lethal mutations

Solution:
H.J. Muller discovered the production of mutations by X-ray irradiation.

Topic: Biology, Principles of Inheritance and Variation, NEET, NEET 2003
Which one of the following does not act as a neurotransmitter?

Options:
A cortisone
B acetylcholine
C epinephrine
D norepinephrine

The correct answer is:
cortisone

Solution:
Cortisone a steroid, a drug that lowers inflammation is a corticosteroid is a pro-hormone that must be reduced to cortisol in order to bind to and activate the glucocorticoid receptor. It promotes the synthesis and storage of glucose and is important in the normal response to stress, suppresses inflammation and regulates deposition of fat in the body. Acetylcholine, epinephrine and norepinephrine are neurotransmitters.
Related Theory
Neurotransmitters are often referred to as the body's chemical messengers. They are the molecules used by the nervous system to transmit messages between neurons, or from neurons to muscles. Communication between two neurons happens in the synaptic cleft. Here, electrical signals that have travelled along the axon are briefly converted into chemical ones through the release of neurotransmitters, causing a specific response in the receiving neuron.

Topic: Biology, Chemical Coordination and Integration, NEET, NEET 2006
Which one of the following does not act as a neurotransmitter ?

Options:
A Epinephrine
B Norepinephrine
C Cortisone
D Acetylcholine

The correct answer is:
Cortisone

Solution:
Epinephrine or adrenaline, norepinephrine or noradrenaline and acetychloline are the neurotransmitters. These are released by the nerve fibres to transmit the impulse to the next neuron. Cortisone is not the neurotransmitter.

Topic: Biology, Neural Control and Coordination, NEET
Which one of the following does not belong to Pteropsida?

Options:
A Selaginella
B Adiantum
C Dryopteris
D Pteris

The correct answer is:
Selaginella

Solution:
Pteridophytes are classified into four classes: Psilopsida (Psilotum), Lycopsida (Selaginella, Lycopodium), Sphenopsida (Equisetum) and Pteropsida (Dryopteris, Pteris, Adiantum).

Topic: Biology, Plant Kingdom, NEET
Which one of the following does not differ in E. coli and Chlamydomonas?

Options:
A Ribosomes
B Cell wall
C Cell membrane
D Nuclear organization

The correct answer is:
Cell membrane

Solution:
Although E. coli is a prokaryotic cell with a peptidoglycan cell wall and Chlamydomonas is eukaryotic with a cellulosic cell wall, but they have cell membrane as a common structure which is essentially the same and is made up of phospholipid bilayer. Other components as mentioned above namely- ribosomes, cell wall & nuclear organization differ in these organisms.

Topic: Biology, Cell - The Unit of Life, NEET
Which one of the following does not differ in E.coli and Chlamydomonas?

Options:
A Ribosomes
B Chromosomal organization
C Cell wall
D Cell membrane

The correct answer is:
Cell membrane

Solution:
Cell membrane of prokaryotes is structurally similar to that of eukaryotes. So, it does not differ in E. coli and Chlamydomonas.

Topic: Biology, Cell - The Unit of Life, NEET, NEET 2012 (Screening)
Which one of the following does not exhibit paramagnetism?

Options:
A NO
B NO2
C CIO2
D CIO2-

The correct answer is:
CIO2-

Solution:
NO, NO2 and ClO2 all have odd number of electrons and therefore are expected to paramagnetic. ClO2- have even number of electrons (17+35=52) , so it may be diamagnetic.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Which one of the following does not exhibit the phenomenon of mutarotation?

Options:
A (+) Sucrose
B (+) Lactose
C (+) Maltose
D (-) Fructose

The correct answer is:
(+) Sucrose

Solution:
Key Idea:- Reducing sugars that exist in hemiacetal and hemiketal forms, undergo mutarotation in aqueous solution.
Among the given carbohydrates, only sucrose is a non-reducing sugar as in it the hemiacetal and hemiketal groups of glucose and fructose are linked together through O-atom and thus, not free. Due to the absence of free hemiacetal or hemiketal group, sucrose does not exhibit mutarotation.

Topic: Chemistry, Biomolecules, NEET, NEET 2010 (Screening)
Which one of the following does not exhibit the phenomenon of mutarotation?

Options:
A (−) Fructose
B (+) Sucrose
C (+) Lactose
D (+) Maltose

The correct answer is:
(+) Sucrose

Solution:
Sucrose does not show muta rotation here while rest other show.

Topic: Chemistry, Biomolecules, NEET
Which one of the following does not exist? (i) XeOF4(ii) NeF2(iii) XeF2(iv) XeF6

Options:
A i) XeOF4ii) NeF2iii) XeF2iv) XeF6
B i) XeOF4ii) NeF2iii) XeF
C i) XeOF4ii) XeF2iii) XeF6
D i) NeF2ii) XeF2iii) XeF6

The correct answer is:
i) XeOF4ii) NeF2iii) XeF

Solution:
Correct Option is : (B)
i) XeOF4ii) NeF2iii) XeF

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET
Which one of the following does not follow the central dogma of molecular biology?

Options:
A Pea
B Mucor
C Chlamydomonas
D HIV

The correct answer is:
HIV

Solution:
The central dogma of proteins synthesis is expressed as
$$
\text { DNA } \stackrel{\text { Replication }}{\longrightarrow} \text { DNA } \stackrel{\text { Transcription }}{\longrightarrow} \text { RNA }
$$
$\stackrel{\text { Translation }}{\longrightarrow}$ Protein
Temin described the presence of an enzyme, reverse transcriptase or RNA dependent DNA polymerase, which controls the synthesis of DNA from a single strand of RNA. D Baltimore also described the presence of this enzyme in RNA tumour viruses. The presence of this enzyme changed the central dogma of protein synthesis into central dogma reverse

Topic: Biology, Molecular Basis of Inheritance, NEET, NEET 2010 (Screening)
Which one of the following ecosystem types has the highest annual net primary productivity?

Options:
A tropical deciduous forest
B temperate evergreen forest
C temperate deciduous forest
D tropical rain forest.

The correct answer is:
tropical rain forest.

Solution:
Productivity of tropical rainforests is the highest. The tropical rainforests coveringan area of $3,00,000 \mathrm{~km}^2$ contain more than $50 \%$ of the total flora and fauna of the world. They are found in the equatorial regions rainfall exceeds $140 \mathrm{~cm}$. The warm humid climate supports broad leaved evergreen plants. Productivity is very high and the vegetation show stratification into two or more well defined layers.

Topic: Biology, Organisms and Populations, NEET, NEET 2007
Which one of the following electrolytes has the same value of van's Hoff's factor (i) as that of Al2SO43 (if all are 100% ionized)?

Options:
A K2SO4
B K3FeCN6
C AlNO33
D K4FeCN6

The correct answer is:
K4FeCN6

Solution:
Al2SO43→2Al3++3SO42- (i=5)
K2SO4→2K++SO42- (i=3)
K3FeCN6→3K++FeCN63- (i=4)
AlNO33→Al3++3NO3- (i=4)
K4FeCN6→4K++FeCN6 4- (i=5)

Topic: Chemistry, Solutions, NEET, NEET 2015 (Phase 1)
Which one of the following electrolytes has the same value of van't Hoff's factor (i) as that of the Al2(SO4)3 (if all are 100% ionised)?

Options:
A K2SO4
B K3[Fe(CN)6]
C K4[Fe(CN)6]
D Al(NO3)3

The correct answer is:
K4[Fe(CN)6]

Solution:
van’t Hoff factor of Al2(SO4)3→2Al+3+3SO4-2
So n=5
K4[Fe(CN)6]→4K++[Fe(CN)6]-4
So n=5
As α=100%=1
i=n=5
In K2SO4 i = 2, In K3[Fe(CN)6] i = 4, In Al(NO3)3 i = 4

Topic: Chemistry, Solutions, NEET
Which one of the following element is important for nitrogen fixation?

Options:
A Zn
B B
C Mo
D Cu

The correct answer is:
Mo

Solution:
Molybdenum is a component of enzyme nitrogenase and nitrate reductase both of which participates in nitrogen metabolism. The enzyme nitrogenase is a Mo-Fe protein and catalyses the conversion of atmospheric nitrogen to ammonia.

Topic: Biology, Mineral Nutrition, NEET
Which one of the following elements in plants is not remobilised?

Options:
A Calcium
B Potassium
C Sulphur
D Phosphorus

The correct answer is:
Calcium

Solution:
Element like calcium are a part of structural component of the cell and hence, are not released. The deficiency symptoms tend to appear first in the young tissues whenever, the elements are not demobilized.

Topic: Biology, Mineral Nutrition, NEET, NEET 2011 (Screening)
Which one of the following elements in plants is not remobilised?

Options:
A	Phosphorus
B Calcium
C Potassium
D Sodium

The correct answer is:
Calcium

Solution:
Elements such as sulphur and calcium are a part of the structural component of the cell and hence, are not easily released. This aspect of mineral nutrition of plants is of great significance and importance to agriculture and horticulture.

Topic: Biology, Mineral Nutrition, NEET
Which one of the following elements is not an essential micronutrient for plant growth?

Options:
A $\mathrm{Zn}$
B $\mathrm{Cu}$
C $\mathrm{Ca}$
D $\mathrm{Mn}$.

The correct answer is:
$\mathrm{Ca}$

Solution:
Essential microelements are $\mathrm{Fe}$, $\mathrm{Mn}, \mathrm{Zn}, \mathrm{B}, \mathrm{Cu}$, Mo and essential macronutrionts areC $\mathrm{H}, \mathrm{N}, \mathrm{P}, \mathrm{S}, \mathrm{Ca}$, $\mathrm{K}, \mathrm{Mg}$.

Topic: Biology, Mineral Nutrition, NEET, NEET 2007
Which one of the following elements is not an essential micronutrient for plant growth?

Options:
A Zn
B Cu
C Ca
D Mn

The correct answer is:
Ca

Solution:
Essential microelements are Fe, Mn, Zn, B, Cu, and Mo. Essential macronutrients are C, H, N, P, S, Ca, K, and Mg.

Topic: Biology, Mineral Nutrition, NEET
Which one of the following elements is unable to form MF63- ion?

Options:
A B
B Al
C Ga
D In

The correct answer is:
B

Solution:
As ‘B’ has no d-orbitals, so it can’t extend its covalency beyond 4. Hence, ‘B’ cannot form the ion like MF 6 3− , i.e., BF 6 3− .
As all other metals have vacant d-orbitals in their valence shells, so they can extend their covalency beyond 4.

Topic: Chemistry, Chemical Bonding and Molecular Structure, NEET
Which one of the following elements is unable to form MF63- ion?

Options:
A B
B Al
C Ga
D In

The correct answer is:
B

Solution:
MF63−
Boron belongs to 2nd period and it does not have vacant d-orbital.
It can form only 3 and 4 bond and cannot form 6 bond.

Topic: Chemistry, p Block Elements (Group 13 & 14), NEET, NEET 2018
Which one of the following elements requires the radiations of highest frequently to cause the emission of electrons?

Options:
A Mg
B Ca
C K
D Na

The correct answer is:
Mg

Solution:
Here Mg requires the radiations of highest frequently to cause the emission of electrons. Radiations of higher frequency to cause the emission of electrons (photoelectric effect) are required by those elements which have higher I.E. Mg and Ca are group 2 elements and Mg has higher I.E. than Ca.

Topic: Chemistry, Structure of Atom, NEET
Which one of the following enzymes contains Mo as the prosthetic group?

Options:
A Phosphatase
B Dehydrogenase
C Isomerase
D Nitrate reductase

The correct answer is:
Nitrate reductase

Solution:
Molybdenum play a important role is nitrogen fixation because it is an activator of nitrate reductase.

Topic: Chemistry, Biomolecules, NEET