CBSE Class 12 Chemistry Biomolecules Assignment

Question. The correct statement in respect of protein haemoglobin is that it:
a. Acts as an oxygen carrier in the blood
b. Forms antibodies and offers resistance to diseases
c. Functions as a catalyst for biological reactions
d. Maintains blood sugar level
Answer : A

Question. The alcohol obtained by the hydrolysis of oils and fats is:
a. Glycol
b. Glycerol
c. Propanol
d. Pentanol
Answer : B

Question. Oleic, stearic and palmitic acids are:
a. Fatty acid
b. Amino acid
c. Nucleic acid
d. Essential acid
Answer : A

Question. The waxes are long chain compounds of fatty acids, which belong to the class of?
a. Esters
b. Ethers
c. Alcohols
d. Acetic acid
Answer : A

Question. Hydrolytic reaction of fats, with caustic soda, is known as:
a. Acetylation
b. Carboxylation
c. Saponification
d. Esterification
Answer : C

Question. An example for a saturated fatty acid, present in nature is:
a. Oleic acid
b. linoleic acid
c. Linolenic acid
d. Palmitic acid
Answer : D

Question. The 'acid value' of an oil or fat is measured in terms of weight of:
a. NH₄OH
b. NaOH
c. KOH
d. CH₃COOH
Answer : C

Question. Hardening of oils is caused by:
a. H₂
b. N₂
c. O₂
d. CO₂
Answer : A

Question. The base present in DNA, but not in RNA is:
a. Guanine
b. Adenine
c. Uracil
d. Thymine
Answer : D

Question. Identify the correct statement regarding enzymes:
a. Enzymes are specific biological catalysts that cannot be poisoned
b. Enzymes are normally heterogeneous catalysts that are very specific in their action
c. Enzymes are specific biological catalysts that can normally function at very high temperature (T ~ 1000K)
d. Enzymes are specific biological catalysts that possess well-defined active sites
Answer : D

Question. The energy change produced by the combustion of food is called the 'calorific value'. The highest calorific value is given by:
a. Proteins
b. Fats
c. Carbohydrates
d. Vitamins
Answer : B

Question. A nucleotide consists of:
a. Base and sugar
b. Base and phosphate
c. Sugar and phosphate
d. Base, sugar and phosphate
Answer : D

Question. The harmone that helps in the conversion of glucose to glycogen in:
a. Adrenaline
b. Insulin
c. Cortisone
d. Bile acids
Answer : B

Question. Which of the following is not a sex hormone?
a. Testosterone
b. Estrone
c. Estradiol
d. Cortisone
Answer : A

Question. The change in optical rotation, with time, of freshly prepared solution of sugar is known as:
a. Rotatory motion
b. Inversion
c. Specific rotation
d. Mutarotation
Answer : D

Question. Mutation of DNA occurs due to changes in the sequence of one of the following:
a. Bases
b. Ribose units
c. Phosphate units
d. Sugar units
Answer : A

Question. Vitamin B₁ is:
a. Riboflavin
b. Cobalamin
c. Thiamine
d. Pyridoxine
Answer : C

Question. An alternation in the base sequence of nucleic acid molecule is called:
a. Replication
b. Mutation
c. Duplication
d. Dislocation
Answer : B

Question. Vitamin B₆ is known as:
a. Pyridoxin
b. Thiamine
c. Tocopherol
d. Riboflavin
Answer : A

Question. Sugar can be tested in urine by:
a. Molisch test
b. Dunstan's test
c. Benedict's test
d. Legal's test
Answer : C

Question. A gene is a segment of a molecule of:
a. DNA
b. m-RNA
c. t-RNA
d. Protein
Answer : D

Question. Amide group is present in:
a. Lipids
b. Carbohydrates
c. Amino acids
d. Proteins
Answer : D

Question. An example of a disaccharide made up of two units of the same monosaccharides is:
a. Sucrose
b. Maltose
c. Lactose
d. None of these
Answer : B

Question. Glucose gives silver mirror with Tollen's reagent. It shows the presence of:
a. An acidic group
b. An alcoholic group
c. A ketonic group
d. An aldehydic group
Answer : D

Question. A certain compound gives negative test with ninhydrin and positive test with Benedict's solution. The compound is:
a. A protein
b. A monosaccharide
c. A lipid
d. An amino acid
Answer : B

Question. Which of the following does not show any reducing test of aldehyde?
a. Sucrose
b. Fructose
c. Maltose
d. Lactose
Answer : A

Question. The aqueous solution of a carbohydrate gives dark blue colour with iodine. It is:
a. Glucose
b. Fructose
c. Sucrose
d. Starch
Answer : D

Question. The ultimate product of oxidation of most of hydrogen and carbon in foodstuffs are:
a. H₂O alone
b. CO₂ alone
c. H₂O and CO₂O
d. None of these
Answer : C

Question. Raffinose is:
a. Trisaccharide
b. Monosaccharide
c. Disaccharide
d. None of these
Answer : A

Question. To become a carbohydrate a compound must contain at least:
a. 2 carbons
b. 3 carbons
c. 4 carbons
d. 6 carbons
Answer : B

Question. The intermediate compound formed in the conversion of starch to glucose is:
a. Lactose
b. Sucrose
c. Maltose
d. Fructose
Answer : C

Question. Glucose and mannose are:
a. Epimers
b. Anomers
c. Ketohexoses
d. Disaccharides
Answer : A

Question. A carbohydrate that cannot be hydrolysed to simpler forms is called
a. Disaccharide
b. Monosaccharide
c. Polysaccharide
d. Trisaccharide
Answer : B

Question. On heating glucose with Fehling's solution we get a precipitate whose colour is:
a. Yellow
b. Red
c. Black
d. White
Answer : B

Question. The charring of sugar, when treated with conc. H₂SO₄, is due to?
a. Oxidation
b. Reduction
c. Dehydration
d. Hydrolysis
Answer : C

Question. Optical activity is shown by
a. Glucose
b. Fructose
c. Sucrose
d. All of these
Answer : D

Question. Which of the following is the sweetest sugar?
a. Glucose
b. Fructose
c. Lactose
d. Sucrose
Answer : B

Question. Which is false?
a. Glucose is a disaccharide
b. Starch is a polysaccharide
c. Glucose and fructose are not anomers
d. Invert sugar consists of glucose and fructose
Answer : A

Question. General formula for carbohydrates is
a. C_nH_2nO_2n+2
b. C_x(H₂O)_2x
c. C_x(H₂O)_y
d. None of these
Answer : C

Question. The disaccharide present in milk is:
a. Maltose
b. Lactose
c. Sucrose
d. Cellobiose
Answer : B