Biomolecules

Which one of the following statements is not true regarding (+) lactose?

1. On hydrolysis (+) lactose gives equal amount of D(+) glucose and D(+) galactose.
2. (+) Lactose is a -glucoside formed by the union of a molecule of D(+) glucose and a molecule of D(+) galactose.
3. (+) Lactose is a reducing sugar and does not exhibit mutarotation.
4. (+) Lactose, C12H22O11 contains 8 –OH groups

Fructose reduces Tollens' reagent due to

1. asymmetric carbons
2. primary alcoholic group
3. secondary alcoholic group
4. enolisation of fructose followed by conversion to aldehyde by base

Which one of the following does not exhibit the phenomenon of mutarotation?

1. (+) Sucrose
2. (+) Lactose
3. (+) Maltose
4. (−) Fructose

The segment of DNA which acts as the instructional manual for the synthesis of the protein is

1. ribose
2. gene
3. nucleoside
4. nucleotide

Which of the following hormones contains iodine?

1. Testosterone
2. Adrenaline
3. Thyroxine
4. Insulin

In DNA, the complementary bases are

1. adenine and guanine; thymine and cytosine
2. uracil and adenine; cytosine and guanine
3. adenine and thymine; guanine and cytosine
4. adenine and thymine; guanine and uracil.

Which of the following is an amine hormone?

1. Insulin
2. Progesterone
3. Thyroxine
4. Oxypurine

RNA and DNA are chiral molecules, their chirality is due to

1. chiral bases
2. chiral phosphate ester units
3. D-sugar component
4. L-sugar component

Which of the following vitamins is water-soluble?

1. Vitamin E
2. Vitamin K
3. Vitamin A
4. Vitamin B

The human body does not produce

1. enzymes
2. DNA
3. vitamins
4. hormones

Which one of the following is a peptide hormone?

1. Adrenaline
2. Glucagon
3. Testosterone
4. Thyroxine

During the process of digestion, the proteins present in food materials are hydrolysed to amino acids. The two enzymes involved in the process Proteins enzyme (A) Polypeptide enzyme (B) Amino acids are respectively

1. invertase and zymase
2. amylase and maltase
3. diastase and lipase
4. pepsin and trypsin

Which functional group participates in disulphide bond formation in proteins?

1. Thioester
2. Thioether
3. Thiol
4. Thiolactone

The cell membranes are mainly composed of

1. fats
2. proteins
3. phospholipids
4. carbohydrates

A sequence of how many nucleotides in messenger RNA makes a codon for an amino acid?

1. Three
2. Four
3. One
4. Two

The hormone that helps in the conversion of glucose to glycogen is

1. cortisone
2. bile acids
3. adrenaline
4. insulin

The correct statement in respect of protein haemoglobin is that it

1. functions as a catalyst for biological reactions
2. maintains blood sugar level
3. acts as an oxygen carrier in the blood
4. forms antibodies and offers resistance to diseases.

Number of chiral carbons in -D-(+)-glucose is

1. five
2. six
3. three
4. four

The helical structure of protein is stabilised by

1. dipeptide bonds
2. hydrogen bonds
3. ether bonds
4. peptide bonds

Which of the following structures represents the peptide chain?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

The enzyme which hydrolyses triglycerides to fatty acids and glycerol is called

1. maltase
2. lipase
3. zymase
4. pepsin

Glycolysis is

1. oxidation of glucose to glutamate
2. conversion of pyruvate to citrate
3. oxidation of glucose to pyruvate
4. conversion of glucose to haem

Phospholipids are esters of glycerol with

1. three carboxylic acid residues
2. two carboxylic acid residues and one phosphate group
3. one carboxylic acid residue and two phosphate groups
4. three phosphate groups

Chargaff's rule states that in an organism

1. amount of adenine (A) is equal to that of thymine (T) and the amount of guanine (G) is equal to that of cytosine (C)
2. amount of adenine (A) is equal to that of guanine (G) and the amount of thymine (T) is equal to that of cytosine (C)
3. amount of adenine (A) is equal to that of cytosine (C) and the amount of thymine (T) is equal to that of guanine (G)
4. amounts of all bases are equal

Enzymes are made up of

1. edible proteins
2. proteins with specific structure
3. nitrogen containing carbohydrates
4. carbohydrates

Which is not a true statement?

1. -carbon of -amino acid is asymmetric
2. All proteins are found in L-form
3. Human body can synthesise all proteins it needs
4. At pH = 7, both amino and carboxylic groups exist in ionised form

Cellulose is polymer of

1. glucose
2. fructose
3. ribose
4. sucrose

Which of the following give positive Fehling solution test?

1. Sucrose
2. Glucose
3. Fats
4. Protein

Which of the following is correct about H-bonding in nucleotide?

1. A-T, G-C
2. A-G, T-C
3. G-T, A-C
4. A-A, T-T

Which of the following is correct?

1. Cycloheptane is an aromatic compound.
2. Diastase is an enzyme
3. Acetophenone is an ether.
4. All of these.