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Right OPTION is (a) α-amino ACIDS

Explanation: Amino acids CONTAIN amino (NH2) and carboxyl (COOH) FUNCTIONAL groups. α-amino acids contain the NH2 group on the carbon adjacent to the COOH group. Proteins on hydrolysis yield only α-amino acids.

The correct option is (c) C2 and C5

To explain I would say: The fructofuranose structure is obtained by the internal ketal formation by combining the keto GROUP at C2 carbon and the OH group at C5 carbon.

The correct choice is (c) It has ‘L’ configuration

To explain: FRUCTOSE is an important ketohexose that naturally occurs in fruits and honey. It has a ketonic GROUP at C2 carbon with six carbon in a straight chain. It belongs to D-series (with respect to glyceraldehyde) and is LAEVOROTATORY.

The correct CHOICE is (a) Deoxyribose

Best explanation: MONOSACCHARIDES are the simplest carbohydrates which cannot be HYDROLYSED into SIMPLER UNITS. Deoxyribose (C5H10O4) is a monosaccharide.

Right choice is (a) STARCH

Explanation: An aqueous SOLUTION of corn starch is acidified with dilute H2SO4. This is then heated under pressure (2-3 bar) for hydrolysis to take place. After this, the liquid is neutralised with sodium carbonate and the resulting solution is concentrated under reduced pressure to get glucose crystals. This process is ALSO USED for obtaining glucose from cellulose.

Right option is (a) sucrose

Explanation: When sucrose (C12H22O11) is boiled with dilute HCL or H2SO4 in an ALCOHOLIC solution, glucose and fructose are obtained in equal AMOUNTS. This is one the METHODS used for preparation of glucose.

The correct choice is (d) Pancreas

Explanation: STEROID HORMONES are produced by adrenal cortex and GONADS. Hormones released by the adrenal cortex PLAY a very important role in the FUNCTIONS of the bod.

The correct answer is (b) C

The best I can explain: B GROUPS vitamins and vitamin C ae soluble in water and are grouped TOGETHER. These must be supplied regularly as they are readily excreted and cannot be stored in the BODY.

Right answer is (a) Peptide bond is formed by the loss of water molecule

Easy explanation: The reaction between two molecules of same of different amino ACIDS proceeds through the linking of COOH group of one and the NH2 group of the other ALONG with the loss of H2O and formation of a peptide bond. The PRODUCT is called a DIPEPTIDE.

Correct OPTION is (d) Histidine

Best explanation: Amino ACIDS can be AROMATIC only if their side chain consists of an aromatic COMPOUND. Methionine has a sulphur containing straight chain. Isoleucine has an isobutyl side group. PROLINE has a complex cyclic side chain. Histidine has a basic aromatic side group, imidazole.

Right CHOICE is (b) Mineralocorticoids

The best I can explain: Mineralocorticoids are steroid HORMONES which control the level of excretion of water and salt by the kidney, thus BALANCING the water and MINERAL LEVELS as required.

Correct choice is (B) tocopherols

For explanation I would say: VITAMIN E is ALSO known as tocopherol. Other compounds that behave like vitamin E also belong to this group. Deficiency of this causes muscular weakness and fragility of red blood CELLS. Its main source is vegetable oils.

The correct choice is (a) MESSENGERS

The explanation: Hormones are CHEMICAL substances produced by the ENDOCRINE glands in the human body. They are carried to DIFFERENT parts of the body through the blood stream. Because of the action of hormones as intercellular COMMUNICATORS, they are called chemical messengers.

Correct choice is (a) A

The explanation: RETINOL, also known as vitamin A, is a vitamin FOUND in food. It is a fat-soluble vitamin also CALLED bright eye vitamin. It helps in the prevention of conditions LIKE XEROPHTHALMIA and night blindness.

The CORRECT ANSWER is (b) False

Easiest explanation: The egg white gets COAGULATED on boiling. The GLOBULAR proteins in egg white (albumin) change to a RUBBER like insoluble mass. This is irreversible denaturation as the protein cannot return to its original state.

The correct option is (a) True

For explanation I would SAY: In an aqueous solution of AMINO acid, COOH loses a proton and NH2 accepts a proton, giving rise to a dipolar zwitter ion. This is neutral but contains both POSITIVE and negative terminals. In this FORM, amino acids react both with acids and bases, and HENCE show amphoteric behaviour.

Correct choice is (B) Sucrose

Best EXPLANATION: Sucrose is widely distributed among plants, particularly sugarcane and SUGAR BEET. The sugar obtained from sugar beet is known as beet sugar, whereas that obtained from sugarcane is cane sugar.

Correct answer is (a) Arabinose

The best I can explain: Arabinose CONSISTS of an aldehydic group (CHO) at the end of its chain which has a total of five carbon atoms (including the CHO group), HENCE it is an aldopentose. XYLULOSE, ribulose and sorbose are examples of KETOSES.

The correct choice is (d) Oxytocin

The best explanation: Oxytocin controls the CONTRACTION of the uterus during child BIRTH and helps in the release of milk from mammary GLANDS. Progesterone is RESPONSIBLE for the preparation of uterus for IMPLANTATION of fertilised egg.

Right choice is (a) EPINEPHRINE

The explanation: Epinephrine and NOREPINEPHRINE are amine HORMONES that mediate response to external stimuli. Adrenaline plays an important role in fight or flight situations by increasing blood FLOW to muscles, blood SUGAR level and pulse rate.

Right option is (d) hypervitaminoses

To ELABORATE: When there is a high DOSE of vitamin intake, there is an APPEARANCE of toxic symptoms, which LEADS to a condition called hypervitaminoses. On the other HAND, the condition of vitamin deficiency is called avitaminoses.

The CORRECT answer is (C) Cellulase

To explain: The ENZYME cellulase hydrolyses cellulose into glucose and THEREBY digests it. However, the human stomach does not produce any enzyme capable of digesting cellulose, and hence it cannot be DIGESTED.

Correct ANSWER is (C) polypeptides

The best I can explain: Almost all enzymes are GLOBULAR proteins, which are nothing but very long CHAINS of amino acids RESIDUES (>100) and higher molecular mass, or polypeptides.

Correct answer is (B) laevulose

The best EXPLANATION: DUE to its laevorotatory BEHAVIOUR, FRUCTOSE is known as laevulose. On the other hand, glucose is known as dextrose for the opposite reason. Fructose can exist as furanose or pyranose depending on its state (free or combined).

The correct CHOICE is (a) PRIMARY

For explanation: Proteins have one or more POLYPEPTIDE CHAINS, in which each chain consists of a specific sequence of amino acids linked with each other. This is called the primary structure and is the most basic level. Any CHANGE in primary structure creates a different protein.

Correct choice is (a) Maltose

For EXPLANATION I WOULD say: When any CARBOHYDRATE UNDERGOES hydrolysis and produces two SEPARATE units of monosaccharides, it is a disaccharide. The used units that are produced may be same. Maltose on hydrolysis gives two units of glucose itself.

The correct answer is (B) INSULIN

The BEST explanation: Insulin consists of a CHAIN of 51 amino acids and HENCE is a polypeptide. Estrogen and androgen are steroids, whereas epinephrine is an amine.

Right CHOICE is (d) OXYTOCIN

Explanation: Amine hormones are water-soluble compounds which have amino groups and are STRUCTURALLY DERIVED from amino acids. Oxytocin is a peptide hormone.

The correct answer is (d) amylopectin; C1-C6

The BEST explanation: Amylopectin is the WATER insoluble branched constituent of starch which makes up 80-85% of its structure. It CONSISTS of straight chains of glucose through C1-C4 linkage, with the C1 of the terminal glucose of each CHAIN linking with the C6 of ANOTHER glucose unit in the next chain.

Correct OPTION is (a) Amino ACID

Explanation: RNA and DNA are nucleic acids which on complete hydrolysis yield a pentose sugar, phosphoric acid and NITROGEN containing heterocyclic COMPOUNDS CALLED bases.

The correct option is (b) α-D-glucose, β-D-fructose

Easy EXPLANATION: SUCROSE is composed of α-D-glucose and β-D-fructose. These TWO are held together by an α,β-glycosidic linkage between C1 of glucose (pyranose) and C2 of fructose (furanose).

Right ANSWER is (d) Tyrosinase

Easy EXPLANATION: Deficiency of tyrosinase results in insufficient production of melanin. This causes a condition of white SKIN and hair called albinism. It can be prevented by including the REQUIRED supply of enzyme through diet.

The correct choice is (d) β-D-(-)-fructopyranose

For explanation I would say: This is the PYRANOSE structure of fructose, where the C2 keto group and C6 OH group are involved in cyclisation. The α and β FORMS in this structure differ based on the arrangement of CH2OH and OH groups around the C2 carbon. Since in this compound, the OH at C2 is in the same side as the OH at C3, it is the β-form.

The CORRECT option is (a) compound on which they work

Easy explanation: Enzymes are GENERALLY NAME after the compound or class of COMPOUNDS on which they work. For example, the catalyst that hydrolyses the REACTION of starch (amylum) to glucose is called as amylase.

Right choice is (a) True

The EXPLANATION: For EXAMPLE, the ACTIVATION energy for acid hydrolysis of SUCROSE is 6.22kJ/mol, while the activation energy is only 2.15kJ/mol when it is HYDROLYSED in the presence of sucrase.

The correct choice is (d) ALBUMIN

The BEST I can explain: Keratin is a FIBROUS protein found in skin, nails, hair and wool. Myosin is present in muscles and COLLAGEN in tendons. Albumin is a GLOBULAR protein.

The CORRECT option is (d) Guanine

To explain I would SAY: The compound shown is β-D-2-deoxyribose which is a PENTOSE SUGAR. It has no oxygen (in the form of HYDROXY) attached to the C2 carbon. It is the sugar moiety in deoxyribonucleic acid (DNA).

Correct answer is (c) D

For explanation I would say: The skin is capable of producing large AMOUNTS of vitamin D when the skin is exposed to sunlight. The part of sunlight that is IMPORTANT is ultraviolet B rays. The DEFICIENCY of vitamin D CAUSES rickets and osteomalacia.

Right CHOICE is (b) dextrorotatory; LAEVOROTATORY

For explanation I would say: Sucrose is dextrorotatory but on hydrolysis GIVES a mixture dextrorotatory glucose and laevorotatory fructose. Since, the specific rotation of fructose is greater than that of glucose, the RESULTANT mixture is laevorotatory.

The correct OPTION is (c) native PROTEIN

Easy explanation: Native state of a protein is its most energetically STABLE state. When a native protein is subjected to PHYSICAL change, the hydrogen bonds are disturbed, and the globules unfold.

Correct option is (c) glycosidic

For explanation: Two monosaccharide units TOGETHER lose a molecule of water and COMBINE by an oxide linkage. Such a BOND between two monosaccharide units through OXYGEN atom is CALLED glycosidic linkage.

The CORRECT option is (a) Sucrose

Easiest explanation: INVERTASE is an enzyme that specifically acts on sucrose. It is NAMED so because it forms invert SUGAR which is a mixture of glucose and fructose.