AIIMS Chemistry Biomolecules Class 12 Questions

Assertion: Two sugar units joined by 1,2-glycosidic bond in sucralose.

Reason: It contains 1 C-glucose and 2 C -fructose glycosidic bond

Assertion : Glucose does not gives 2,4-DNP test

Reason : Glucose exists in cyclic hemiacetal form

Which is the chemical test for polysaccharide?

Select the correct set of answer:

Assume that a particular amino acid has an isoelectric point of $6.0$. In a solution of $\text{pH } 1.0$, which of the following species will predominate?

In the primary structure of proteins, the amino acids are interconnected by-

Assertion : The penta-acetate of glucose does not react with hydroxylamine.

Reason : This is because free aldehyde group is not present in penta-acetate.

1. Match the column-I and column-II

Amylopectin is

Polysaccharides can be tested by

Protein on reaction with which yields Ruhemann's purple?

Which of the following are all Nucleotides

Match the column

Which of the following is a nucleoside?

Nucleoside is:

Which of the following linkage is found in sucrose?

Assertion: Glycosidic bonds are formed by dehydration.

Reason: In polysaccharides, individual monosaccharide is linked by glycosidic bond.

Assertion : Human diet should compulsorily contain glycine, serine and tyrosine.

Reason : Essential amino acids cannot be synthesized in the human body.

$2\text{ICl} \rightarrow \text{I}_2 + \text{Cl}_2 \quad K_c = 0.14$If initial concentration of $\text{ICl}$ is $0.6\text{ M}$,

then equilibrium concentration of $\text{I}_2$ is:

Structure of Guanine is

Assertion : Boiling point of $\alpha\text{-D-glucose}$ is less than $\beta\text{-D-glucose}$.

Reason : $\beta\text{-D-glucose}$ is more stable than $\alpha\text{-D-glucose}$.

Assertion: Tyrosine behave as a acidic at pH = 7 Reason: pKₐ of phenol is mole than 7.

Assertion: A solution of sucrose in water is dextrorotatory but on hydrolysis in presence of little hydrochloric acid, it becomes laevorotatory. Reason: Sucrose on hydrolysis gives unequal amounts of glucose and fructose as a result of which change in sign of rotation is observed.

Assertion : Proteins are made up of $\alpha$-aminoacids.

Reason : During denaturation, secondary and tertiary structures of proteins are destroyed.

How many polypeptide chains are there in 1 Hb molecule?

Which of the following is incorrect?

Examples of essential amino acids are –

Select the option having correct matching of structure and sequence of the molecules given below –

Which of the following is/are essential fatty acid(s)?

The nitrogen base which is present in RNA and absent in DNA is

In the following questions a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the correct answer out of the following choice.

Assertion (A) Glucose gives reddish brown precipitate with Fehling solution.

Reason (R) Reaction of glucose with Fehling solution gives CuO and gluconic acid.

Read the Assertion and Reason carefully to mark the correct option from those given below Assertion The structure given is the most important animal steroid which is insoluble in water and chemically unreactive.

Glucose → HCN → Hydrolysis → HI, heat → A, A is

Among the following, the achiral amino acids is

Assertion: A solution of sucrose in water is dextrorotatory. But on hydrolysis in the presence of a little hydrochloric acid, it becomes laevorotatory. Reason: Sucrose on hydrolysis gives unequal amounts of glucose and fructose. As a result of this, change in sign of rotation is observed.

Identify the given structure.

Assertion (A) A solution of sucrose in water is dextrorotatory while on hydrolysis in presence of little hydrochloric acid, it becomes laevorotatory.

Reason (R) Sucrose on hydrolysis gives unequal amounts of glucose and fructose as a result of which change in sign of rotation is observed.

Which one of the following is a conjugated protein?

Which of the following is a non-reducing sugar?

Assertion: All enzymes are made up of proteins and all proteins have three dimensional structures. Reason: Secondary structures of protein are sequence of amino acids.

Which of the following is a homopolysaccharide?

Find the hydrolysis product when a phosphodiester bond of nucleotide breaks.

Find the hydrolysis product of maltose.

Assertion : β-pleated sheet structure of protein shows maximum extension.

The element which is the most abundant in the earth crust is

Assertion : Alpha (α)⁻amino acids exist as internal salt in solution as they have amino and carboxylic acid groups in near vicinity.

Reason : H⁺ ion given by carboxylic group (–COOH) is captured by amino group (–NH₂) having lone pair of electrons.

The pair in which both species have iron is

Among the following L⁻serine is

Thymine is

Lysine is least soluble in water in the pH range