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Correct option (A) Hypothalamus

Explanation:

Oxytocin and Vasopressin synthesised in hypothalamus then comes into neurohypophysis of pituitary gland to release in blood

[Given answer by KVPY is C]

Answer is : (b) kidney

Erythropoietin (EPO) is a hormone produced by the kidney that promotes the formation of red blood cells by the bone marrow. Chemically, erythropoietin is a protein with an attached sugar (a glycoprotein). It is produced by kidney cells when the body experiences low oxygen level. The resulting rise in red-blood cells increases the oxygen carrying capacity of the blood.

Answer is : (b) Kidney

Kidneys are not associated with the production of white blood cells. Kidneys regulate blood volume and composition, release erythropoietin and excrete waste in the urine.

Bone marrow is involved in hematopoiesis. It is the site of B-lymphocytes synthesis and maturation.

Liver produces monocytes (a type of white blood cells).

In spleen, B and T-lymphocytes are present. 50% of spleen cells are B-lymphocytes and 30-40% are T-lymphocytes.

Correct option is (a) Residual Volume (RV)

In lungs, even after the most forceful expiration, some of the volume of air remains. This volume is termed Residual Volume (RV). Due to this, lungs do not collapse even after the most forceful expiration. RV is about 1100-1200 ml.

Correct option is (b) halophytes

Plants that produce pneumatophores i.e. negatively geotropic roots and show vivipary i.e. germination of seeds inside the fruits are halophytes.

These plants are adapted to grow in highly saline areas such as mangroves. Pneumatophores help these plants in respiration as they do not get sufficient oxygen from the soil. On the other hand vivipary aids in perennation.

Correct option is (d) RNA molecules without protein coat 5

Viroids differ from viruses in having RNA molecules without protein coat. Viruses on the other hand possess DNA or RNA with a protein coat as their genetic material. Viruses can infect a wide range of organisms including plants, animals or bacteria, while viroids infect only plants.

Correct option is (a) Insulin

Insulin is the peptide hormone which enhances the uptake of glucose molecules by liver cells (hepatocytes) and fat cells (adipocytes) for its cellular utilisation. Such an activity of insulin brings down the level of glucose in the blood.

Correct option  (C) capacitance of the bird is too small and the line frequency is too small. 

Explanation:

X_c = 1/ωC = is very large therefore bird does after very high capacitive reactance in the path of A.C. current.

Answer is : (d) Polarisation

Polarisation is a process of alignment of electric vectors (or plane of oscillation of particles) in a particular direction when an electromagnetic wave (or a mechanical transverse wave) passes through a narrow slit. Sound waves in air are longitudinal waves, so they cannot be polarised. Polarisation is shown only by transverse waves.

Correct option: (D) Polarization

Answer is : (d) filled with CS₂ and immersed in water

When medium outside a lens is denser than medium of lens, then a concave lens will acts like a convex lens and vice-versa.

Now, when hollow lens is filled with CS₂ (η = 1.6) and immersed in water (η = 1.33), its nature remains diverging as refractive index of medium of lens is more than refractive index of surrounding medium.

Answer is : (a) CO, N₂ and (d) F₂, HCl

Isoelectronic species are those species, which have same number of electrons. The total number of electrons in each pair given in the options are as follows

(a) CO, N₂

No. of electrons in CO = 6+8 = 14

No. of electrons in N₂ = 7+7 = 14

(b) O₂, NO

No. of electrons in O₂ = 8+8 = 16

No. of electrons in NO = 7+8 = 15

(c) C₂, HF

No. of electrons in C₂ = 6+6 = 12

No. of electrons in HF = 1+9 = 10

(d) F₂, HCl

No. of electrons in F₂ = 9+9 = 18

No. of electrons in HCl = 1+17 = 18

Thus, CO and N₂, F₂ and HCl are isoelectronic pairs.

Answer is : (c) Acetaminophen

Acetaminophen, also known as paracetamol is not produced by plant or fungi, it is artificially formed. The starting material for the manufacturing of paracetamol is phenol which is nitrated to give a mixture of the ortho and para-nitrotoluene.

Other drugs are obtained as, penicillin is an antibiotic obtained from ascomycetous fungi Penicillium notatum. Reserpine is an alkaloid derived from the roots of Rauwolfia serpentina plant. Quinine comes from the bark of the Cinchona tree.

Correct option  (A) arginine, lysine

Explanation:

Histone is basic protein and it is rich in lysine and arginine

Correct option is (c) A part of the transfer RNA molecule which recognises the triplet code on the messenger RNA

The triplet codon is made up of 3 nucleotide bases and is located at the centre of the middle loop of tRNA molecule and base pairs with the complementary bases on an mRNA molecule during protein synthesis.

Correct option is (b) ATP and reduced NADP are not produced

Only the electron transport system produces ATP and reduced NADP in the plant. Without these compounds, the Calvin cycle cannot proceed and carbon-fixation cannot occur and their is no respiratory substrate available for respiration.

Correct option is (a) Parietal bone and the temporal bone of the skull are joined by fibrous joint

Immovable / fixed / fibrous joints are present between the skull bones. So, between parietal bone and the temporal bone of the skull are joined by fibrous joint. Other statements can be corrected as First cervical vertebra is atlas not axis. The 11th and 12th pairs of ribs are called floating ribs. Glenoid cavity is located at the end of scapula close to coracoid process.

Answer is : (b) Hydathodes

Hydathodes are involved in guttation. Hydathodes are specialised pore located along the leaf margins and tip which secrets water droplets. The exudation of water droplets from the tip or margin of the leaves is called guttation. Hydathodes mediated guttation occurs under high humidity and in the absence of transpiration.

Cuticle is an extracellular layer which covers the epidermis of plants which provides protection against dessication and external environmental stress.

Lenticels and stomata both regulates gaseous exchange between internal plant tissues and atmosphere and also regulates water movement through transpiration.

Answer is : (b) K > Mg > Zn > Au

The reactivity of K, Mg, Au and Zn with water can be determined by the reactivity series of metals. According to reactivity series, the decreasing order of reactivity will be

K > Mg > Zn > Au

Correct option (A) 1/8 and 1/2

Explanation:

Corner ⇒ 1/8 

Face ⇒ 1/2

Correct option(b)

Explanation:

E⁰_red = K < Mg < Zn < Au

Answer is : (a) pH decreases when solid ammonium chloride is added to a dilute aqueous solution of NH₃

Dil.aqueous solution of NH₃ is NH₄OH.

NH₄OH ⇌ NH₄⁺ + OH^-

On adding solid ammonium chloride

NH₄Cl → NH₄⁺ + Cl^-

The reaction moves backward due to common ion effect. The concentration of OH⁻ decreases and hence the pH decreases.

Answer is : (d) Cs > K > Na > Li

On moving down the group, as the atomic number of alkali metal increases, their atomic radii also increases because here shielding effect predominates over nuclear charge. Thus, the correct order of atomic radii of alkali metal is

Cs > K > Na > Li

Answer is : (d) Na > Li > Si > F

Among the given elements Li and Na belong to group 1, i.e. they are alkali metals. So, they will have maximum atomic radii. Between Li and Na, Na will have the largest atomic radii. This is because as we move down the group atomic radii increases.

Si belongs to group 14 and F belongs to group 17. So, as we move from left to right in period the atomic radii decreases. Thus, Si will have large atomic radii than F but less than Li.

So, the correct order of atomic radii of given elements is, Na > Li > Si > F.

Answer is : (a) K < Na < Li < H

As the atomic number increases, the energy of orbital decreases. This is because the atomic radii decreases (nuclear charge increases) with increase in atomic number. The atomic number of H, Li, Na and K respectively, are 1, 3, 11 and 19. Thus, the correct order of energy of 2s-orbitals is

K < Na < Li < H.

Answer is : (a) i and ii

(i) Energy of the 2s orbital of different elements decreases as nuclear charge (equal to atomic number) of atom increases.

(ii) There are n² orbitals in a shell with principal quantum number n.

∴ total number of electrons = 2n².

(iii) Extra stability of half-filled orbitals is due to greater exchange energy.

(iv) For two electrons will be in the same orbital, their spin quantum numbers must be different.

It is not irrespective of their spin.

Correct option is (c) auxins

Auxin delays abscission of leaves and fruits at early stages. Whenever leaf or fruit fall occurs, the organ concerned stops producing auxin. However, it promotes abscission of older, mature leaves and fruits.

Correct option is (b) Formation of acetyl Co-A

If O₂ is not available, pyruvic acid undergoes anaerobic respiration / fermentation, but under aerobic condition, the pyruvic acid enters into mitochondria and converted to acetyl Co-A. Acetyl Co-A functions as substrate entrant for Krebs’ cycle. So, it is a connecting link between glycolysis and Kreb’s cycle.

The Correct option is (C) ~30 percent 

Answer is : (c) ~ 30 per cent

The energy assimilated by the herbivores is used in respiration and a fraction of unassimilated energy is transferred to decomposers (e.g. faecal matter). With increasing trophic levels, the respiration cost also increases sharply. On an average, producers consume about 20% of their gross productivity in respiration. The herbivores consume about 30% of assimilated energy in respiration. In carnivores, the proportion of assimilated energy consumed in respiration rises to about 60%.

Correct option  (D) HF 

Explanation:

μ∝ ΔE.N

So HF has highest value of dipole moment

Correct option  (C) Al 

Explanation:

Aluminium form amphoteric oxide with oxygen (Al₂O₃) 

Answer is : (d) Chain isomerism

As pentan-2-one (CH₃COCH₂CH₂CH₃) and 3-methyl butanone (CH₃COCH(CH₃)CH₃) have similar molecular formula, but different carbon skeletons. Thus, they are chain isomers and will exhibit chain isomerism.

Correct option  (A)  IgD : viral pathogen

Explanation:

IgD activates , B- lymphocyte

Correct option  (B) Ninhydrin

Explanation:

Ninhydrin stain is used to detect primary or secondary amino acid and ammonia. 

Ninhydrin used to detect amino acids.

The correct option is (A) IgD: viral pathogen.

A solid expands upon heating because  the potential energy of interaction between atoms in the solid is asymmetric about the equilibrium positions of atoms

Correct option  (B) move with greater speed and are larger in size than in the rest of the pipe 

Explanation:

According to Bernoulli theorem In the region of narrow cross section of pipe, KE of fluid will be greater and pressure energy will be lesser. ⇒ less pressure results into larger in size of air bubble and greater KE results its greater speed. 

Correct option is (d) chitin

Cell wall of the most fungi is made up of chitin. Chemically it is N-acetyl glucosamine. It is found in the exoskeleton of insects.

Correct option  (A) it absorbs longer wavelengths of the electromagnetic spectrum while transmitting shorter wavelengths.

Explanation:

Absorbs infrared radiation thus it absorbs longer wavelength of EM wave spectrum while transmitting shorter wavelength.

Answer is : (a) it absorbs longer wavelengths of the electromagnetic spectrum while transmitting shorter wavelengths

Heat through sun reaches earth in form of infrared radiations of higher frequency range approx 10¹⁴ Hz. This heat is absorbed by solids on earth’s surface and they re-radiate this heat in form of infrared radiations of lower frequency range approx 10¹⁰ Hz. These radiations are absorbed by greenhouse gases like methane and does not escapes into space causing warming of earth’s atmosphere.

Correct option  (B) photosystem II from carbon dioxide. 

Explanation:

photosynthesis at Ps II in lumen of thylakoid

Correct option  (D) Alleles are non-heritable.

Explanation:

Alleles are alternate form of gives of one character present on same locus. 

Correct option   (C) Only Law of independent assortment 

Explanation:

Linkage in exception of law of independent assortment

Correct option  (B) 6

Explanation:

n(n + 1)/2  =  3(3 + 1) =  6

(B)Bag in 'P' becomes turgid due to endosmosis 

Answer is : (c) mitochondria

A mature RBC lacks nucleus, mitochondria and endoplasmic reticulum. In humans, mature RBCs are flexible and oval biconcave disks. They lack a cell nucleus and most organelles, in order to accommodate maximum space for haemoglobin.

Answer is : (a) Bowman’s capsule

Podocytes are cells of squamous epithelium of Bowman capsule of nephron. The Bowman’s capsule filters the blood, retaining large molecules such as proteins while smaller molecules such as water, salts and sugars are filtered as the first step in the formation of urine.