KVPY Class-XII ...

Let a, b, c, d and e be real numbers such that a + b < c + d, b + c < d + e, c + d < e + a, and d + e < a + b. Then,

A carrot looks orange in colour because of the β- carotene molecule in it. This means that the β- carotene molecule absorbs light of wavelengths

Which of the following is NOT an oxidation-reduction reaction?

The thermal stability of alkaline earth metal carbonates MgCO₃, CaCO₃, SrCO₃ and BaCO₃ follows the order:

Among the following metals, the strongest reducing agent is

The molecule which is NOT hydrolysed by water at 25°C is

Among the following compounds, the one which does NOT produce nitrogen gas upon heating is

Interferons combat viral infection by

Leydig cells synthesise

Glucagon increases the blood glucose concentration by

Which among the following is/are NOT essential for polymerase chain reaction (PCR)?

CO₂ acts as a greenhouse gas because

A graph of species richness vs area on log-log axes is

Concentration of Na⁺ ions outside a nerve cell is ~ 100 times more than that inside. The concentration of K⁺ ions is more inside the cells. The levels of Na⁺ ions and K⁺ ions are maintained by

In a chemical reaction, enzymes catalyse the reaction by

The rigidity of cellulose is due to

Antigen-antibody reactions

Which of the following combinations of molecular masses of polypeptides are obtained from purified human IgM when analysed on sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions?

Two genetic loci controlling two different traits are linked. During the inheritance of these traits, the Mendelian law(s) that would be affected is/are:

Which of the following statements is INCORRECT?

Which of the following statements is INCORRECT about restriction endonucleases?

The number of net ATP molecules produced from 1 glucose molecule during glycolysis is

Which of the following co-enzymes is required for the conversion of L-alanine to a racemic mixture of D-and L-alanine?

The cyclic electron flow during photosynthesis generates

Match the type of cells given in Column I with organisms given in Column II. Choose the appropriate combination from the options below.

Compared to the atmospheric air, the alveolar air has

Let x, y, z be positive integers, such that HCF (x, y, z) = 1 and x² + y² = 2z². Which of the following statements is/are true?

I. 4 divides x or 4 divides y.
II. 3 divides x + y or 3 divides x - y.
III. 5 divides z(x² - y²).

A mixture of toluene and benzene boils at 100^oC. Assuming ideal behaviour, the mole fraction of toluene in the mixture is closest to [Vapour pressures of pure toluene and pure benzene at 100^oC are 0.742 and 1.800 bar, respectively. 1 atm = 1.013 bar]

The genetic distance between genes A and B is 10 cm. An organism with Ab combination of the alleles is crossed with an organism with aB combination of alleles. What will be the percentage of the gametes with AB allele combination by an F1 individual?

Proteins P, Q, and R are associated with intact organellar membrane in a cell. If the intact organelle is treated with a high ionic strength buffer, only protein R remains associated with the membrane fraction. Based on this, one could conclude that

In photosynthesis, oxygen is produced by

How many different proteins consisting of 100 amino acids can be formed from 20 different amino acids?

Which of the following options is TRUE with respect to emigration?

Choose the CORRECT statements from below related to cysteine residue in proteins:

i. Cysteine can be linked to tyrosine by S-O bond.
ii. Cysteine can be linked to another cysteine by S-S bond.
iii. Cysteine can complex with Zn²⁺.
iv. Cysteine can be linked to methionine by S-S bond.

The minimum number of plants to be screened to obtain a plant of the genotype AabbCcDd from a cross between plants of genotypes AaBbCcDd and AABbCCDd is

When a pure bred, red flower-producing plant of genotype RR is crossed with a pure bred, white flower-producing plant of genotype rr, all the plants produce pink flowers. If all the plants in each generation from F₁ to F₆ are selfed, then what will be the percentage of plants with red and white flowers in the final population consisting of a large number of individuals? (Consider that flower colour has no effect on reproduction and survival)