Question 511 Mark
Write the constituents of sucrose.
Answer
View full question & answer→D-(+)- Glucose and D-(-)- fructose.
Questions · Page 2 of 2
1 Marks Question
Question 521 Mark
Name the enzyme that breaks large protein into small peptides.
Answer
View full question & answer→Pepsin, trypsin.
Question 531 Mark
Deficiency of which vitamin causes beri-beri and pain in joints?
Answer
View full question & answer→Vitamin B1.
Question 541 Mark
What are glycosidic linkages? In which type of biomolecules are they present?
Question 551 Mark
Amino acids can be classified as $\alpha-, \beta-, \delta-,$and so on depending upon the relative position of amino group with respect to carboxyl group. Which type of amino acids form polypetide chain in proteins?
View full question & answer→
Question 561 Mark
Why must vitamin C be supplied regularly in diet?
Answer
View full question & answer→Vitamin C are soluble in water. Water soluble vitamins must be supplied regularly in diet because they are readily excreted in urine and cannot be stored in our body.
Question 571 Mark
How do enzymes help a substrate to be attacked by the reagent effectively?
Answer
View full question & answer→Enzymes arehighly specific. They react with substrate molecule and form intermediate complex. They reduce the magnitude of activation energy.
Question 581 Mark
Why is cellulose not digested in human body?
Answer
View full question & answer→It is due to the fact that human beings do not have enzyme to digest cellulose.
Question 591 Mark
Answer the following questions.
Which of the following biomolecules is insoluble in water? Justify. Insulin, Haemoglobin, Keratin.
Which of the following biomolecules is insoluble in water? Justify. Insulin, Haemoglobin, Keratin.
Answer
View full question & answer→Keratin being a fibrous protein insoluble in water.
Question 601 Mark
Write biological importance of nucleic acid.
Answer
View full question & answer→- To transmit genetic material to their offsprings.
- Protein synthesis.
Question 611 Mark
What are oligosaccharides?
Answer
View full question & answer→Carbohydrates which on hydrolysis give 2-10 molecules of monosaccharides are called oligosaccharides. For example, sucrose, raffinose, stachyose, etc.
Question 621 Mark
How do you explain the presence of five —OH groups in glucose molecule?
Answer
View full question & answer→Glucose gives penta-acetyl derivative on acetylation with acetic anhydride.
$\text{CHO}| (\text{CHOH})_4|\text{CH}_2\text{OH}|\text{CH}_2\text{OH}\xrightarrow{\ \ \ \ \ \ \ \ \ }\text{CHO}|(\text{CHOCOCH}_3)_4|\text{CH}_2\text{OH}_2\text{OCOCH}_3$
This confirms the presence of five -OH groups.
$\text{CHO}| (\text{CHOH})_4|\text{CH}_2\text{OH}|\text{CH}_2\text{OH}\xrightarrow{\ \ \ \ \ \ \ \ \ }\text{CHO}|(\text{CHOCOCH}_3)_4|\text{CH}_2\text{OH}_2\text{OCOCH}_3$
This confirms the presence of five -OH groups.
Question 631 Mark
Monosaccharides contain carbonyl group hence are classified, as aldose or ketose. The number of carbon atoms present in the monosaccharide molecule are also considered for classification. In which class of monosaccharide will you place fructose?
Answer
View full question & answer→Monosaccharides contain carbonyl group. Hence, are classified as aldose or ketose.
When aldehyde group is present, the monosaccharides are known as aldose. When ketone group is present, the monosaccharides are known as ketose. Fructose has molecular formula C6H12O6 containing six carbon and keto group and is classified as ketohexose.
When aldehyde group is present, the monosaccharides are known as aldose. When ketone group is present, the monosaccharides are known as ketose. Fructose has molecular formula C6H12O6 containing six carbon and keto group and is classified as ketohexose.
Question 641 Mark
The letters ‘D’ or ‘L’ before the name of a stereoisomer of a compound indicate the correlation of configuration of that particular stereoisomer. This refers to their relation with one of the isomers of glyceraldehyde. Predict whether the following compound has ‘D’ or ‘L’ configuration.
Answer
View full question & answer→The letters ‘D’ or ‘L’ before the name of any compound indicate the relative configuration of a particular stereoisomer. This refers to their relation with a particular isomer of glyceraldehydes.
D’ before the name of glucose represents the configuration whereas ‘(+)’ represents dextrorotatory nature of the molecule. It may be remembered that ‘D’ and ‘L’ have no relation with the optical activity of the compound. For assigning the configuration of monosaccharides, it is the lowest asymmetric carbon atom which is compared. The given compound has L-configuration.
D’ before the name of glucose represents the configuration whereas ‘(+)’ represents dextrorotatory nature of the molecule. It may be remembered that ‘D’ and ‘L’ have no relation with the optical activity of the compound. For assigning the configuration of monosaccharides, it is the lowest asymmetric carbon atom which is compared. The given compound has L-configuration.
Question 651 Mark
Give the chemical name of Vitamin B12.
Answer
View full question & answer→Cyanocobalamin.
Question 661 Mark
Under what conditions glucose is converted to gluconic and saccharic acid?
Answer
View full question & answer→Glucose is converted to gluconic acid by Br2 water and to saccharic acid by cone HNO3.
$\ \text{CHO} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH} \\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \text{(CHOH)}_4 + \text{O} \xrightarrow{\text{Br}_2/\text{H}_2\text{O}}(\text{CHOH})_4\\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \ \text{CH}_2\text{OH} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH} \\ \text{Glucose} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Gluconoc acid}$
$\ \text{CHO} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH} \\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \text{(CHOH)}_4 +3[ \text{O}] \xrightarrow{\text{Br}_2/\text{H}_2\text{O}}(\text{CHOH})_4\\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \ \text{CH}_2\text{OH} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH} \\ \text{Glucose} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Saccharic acid}$
$\ \text{CHO} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH} \\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \text{(CHOH)}_4 + \text{O} \xrightarrow{\text{Br}_2/\text{H}_2\text{O}}(\text{CHOH})_4\\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \ \text{CH}_2\text{OH} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH} \\ \text{Glucose} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Gluconoc acid}$
$\ \text{CHO} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH} \\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \text{(CHOH)}_4 +3[ \text{O}] \xrightarrow{\text{Br}_2/\text{H}_2\text{O}}(\text{CHOH})_4\\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \ \text{CH}_2\text{OH} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH} \\ \text{Glucose} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Saccharic acid}$
Question 671 Mark
What are the ultimate products of digestion of proteins?
Answer
View full question & answer→Amino acids.
Question 681 Mark
Name two diseases caused due to deficiency of enzymes.
Answer
View full question & answer→Albinism and phenylketonuria.
Question 691 Mark
How do you explain the presence of an aldehydic group in a glucose molecule?
Answer
View full question & answer→Glucose gets oxidised to six carbon carboxylic acid (gluconic acid) on reaction with a mild oxidising agent like bromine water. This indicates that the carbonyl group is present as an aldehydic group.
$\ \text{CHO} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH} \\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \text{(CHOH)}_4 \xrightarrow{\text{Br}_2/\text{H}_2\text{O}}(\text{CHOH})_4\\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \ \text{CH}_2\text{OH} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH} \\ \text{Glucose} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Glucose acid}$
$\ \text{CHO} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{COOH} \\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \text{(CHOH)}_4 \xrightarrow{\text{Br}_2/\text{H}_2\text{O}}(\text{CHOH})_4\\ \ \ {|} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ {|} \\ \ \text{CH}_2\text{OH} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_2\text{OH} \\ \text{Glucose} \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{Glucose acid}$
Question 701 Mark
What is function of 'fibrinogen' in the blood?
Answer
View full question & answer→It helps in protective blood clotting.
Question 711 Mark
Name the sugar present in milk. How many monosaccharide units are present in it? What are such oligosaccharides called?
Answer
View full question & answer→Lactose is present in milk. Two monosaccharide units (i.e., glucose and galactose) are present in it. Such oligosaccharides are called disaccharides.
Question 721 Mark
In nucleoside a base is attached at 1′ position of sugar moiety. Nucleotide is formed by linking of phosphoric acid unit to the sugar unit of nucleoside. At which position of sugar unit is the phosphoric acid linked in a nucleoside to give a nucleotide?
Answer
View full question & answer→Phosphoric acid unit is linked preferably at 5′-position of sugar moiety of a nucleoside to give a nucleotide.
Question 731 Mark
Aldopentoses named as ribose and 2-deoxyribose are found in nucleic acids. What is their relative configuration?
Answer
View full question & answer→Configuration assigned is O. Thus, ribose is $\beta-$D-ribose Deoxyribose is $\beta-$D-2-deoxyribose.
Question 741 Mark
Write IUPAC names of the following compounds and classify them into primary, secondary and tertiary amines.
(CH3)3CNH2
(CH3)3CNH2
Answer
View full question & answer→(CH3)3CNH2
Tert-butylamine (primary amine)
Tert-butylamine (primary amine)
Question 751 Mark
Answer the following questions.
Name the protein and its shape present in oxygen carrier in human body.
Name the protein and its shape present in oxygen carrier in human body.
Answer
View full question & answer→Globular protein and its shape is spherical.
Question 761 Mark
Give one example of a denaturated protein.
Answer
View full question & answer→Curdling of milk.
Question 771 Mark
Name two carbohydrates which act as biofuels.
Answer
View full question & answer→Starch and glycogen.
Question 781 Mark
Why does compound (A) given below not form an oxime?
Answer
View full question & answer→Glucose pentaacetate (structure A) doesn’t have a free —OH group at C1 and so can’t be converted to the open chain form to give —CHO group and hence doesn’t form the oxime.
Question 791 Mark
Name two of the different types of RNA molecules found in the cells of organisms.
Answer
View full question & answer→Messenger RNA (mRNA) and transfer RNA (tRNA).
Question 801 Mark
Among the amino acids phenylalanine, glutamine and alanine which one is an essential amino acid?
Answer
View full question & answer→Phenylalanine is an essential amino acid.
Question 811 Mark
Some enzymes are named after the reaction, where they are used. What name is given to the class of enzymes which catalyse the oxidation of one substrate with simultaneous reduction of another substrate?
Answer
View full question & answer→Oxidoreductase is class of enzymes which catalyse the oxidation of one substrate with simultaneous reduction of another substrate.
Question 821 Mark
Write IUPAC names of following and classify them into primary, secondary, tertiary amines:
CH3NHCH(CH3)2
CH3NHCH(CH3)2
Answer
View full question & answer→CH3NHCH(CH3)2
Methyl isopropyl amine (secondary)
Methyl isopropyl amine (secondary)
Question 831 Mark
Which moieties of nucleosides are involved in the formation of phosphodiester linkages present in dinucleotides? What does the word diester in the name of linkage indicate? Which acid is involved in the formation of this linkage?
Question 841 Mark
How do you explain the presence of all the six carbon atoms in glucose in a straight chain?
Answer
View full question & answer→On prolonged heating with HI, glucose gives n-hexane.
$\text{Glucose}\ \xrightarrow{\ \ \ \ \ \ \ \ \ \ \text{HI} }\text{CH}_{3}-\text{CH}_{2}-\text{CH}_{2}-\text{CH}_{2}-\text{CH}_{3}$
$\text{Glucose}\ \xrightarrow{\ \ \ \ \ \ \ \ \ \ \text{HI} }\text{CH}_{3}-\text{CH}_{2}-\text{CH}_{2}-\text{CH}_{2}-\text{CH}_{3}$
Question 851 Mark
Name the linkage connecting monosaccharide units in polysaccharides.
Answer
View full question & answer→Glycosidic linkage.
Question 861 Mark
Among B group vitamins B1, B2, B6 and B12 which vitamin can be stored in our body?
Answer
View full question & answer→Vitamin B12.
Question 871 Mark
Activation energy for the acid catalysed hydrolysis of sucrose is 6.22kJ mol–1, while the activation energy is only 2.15kJ mol–1 when hydrolysis is catalysed by the enzyme sucrase. Explain.
Answer
View full question & answer→Enzymes are biocatalysts. They reduce the magnitude of activation energy by providing alternative path. In the hydrolysis of sucrose, the enzyme sucrase reduces the activation energy from 6.22kJ mol-1 to 2.15kJ mol-1. As a result, enzyme catalysed reactions occur at a much faster rate than the ordinary chemical reactions using conventional catalysts.
Question 881 Mark
Name the vitamin whose deficiency is responsible for poor coagulation of blood.
Answer
View full question & answer→Vitamin K.
Question 891 Mark
Name the enzymes present in the saliva of human beings.
Answer
View full question & answer→Amylase.
Question 901 Mark
Structures of glycine and alanine are given below. Show the peptide linkage in glycylalanine.
$\text{H}_{2}\text{N}-\text{CH}_{2}-\text{COOH} :\text{H}_2\text{N}-\text{CH}_2-\text{COOH}\\\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_3$
View full question & answer→$\text{H}_{2}\text{N}-\text{CH}_{2}-\text{COOH} :\text{H}_2\text{N}-\text{CH}_2-\text{COOH}\\\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ |\\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{CH}_3$
Question 911 Mark
Out of lysine and leucine which one is a basic amino acid?
Answer
View full question & answer→Lysine.
Question 921 Mark
Deficiency of which vitamin causes scurvy?
Answer
View full question & answer→Vitamin C.
Question 931 Mark
The deficiency of which vitamin causes the disease 'pernicious anaemia'?
Answer
View full question & answer→Vitamin B12.
Question 941 Mark
Name the molecule which provides energy for all the activities of a cell.
Answer
View full question & answer→Adenosine triphosphate (ATP).
Question 951 Mark
During curdling of milk, what happens to sugar present in it?
Answer
View full question & answer→When milk is curdeled, its sugar get oxidize to form lactic acid.
Question 961 Mark
$\alpha-$Helix is a secondary structure of proteins formed by twisting of polypeptide chain into right handed screw like structures. Which type of interactions are responsible for making the $\alpha-$helix structure stable?
Answer
View full question & answer→In $\alpha-$helix, apolypeptide chain is stabilized by the formation of hydrogen bonds between NH— group of amino acids in one turn with the >C —O groups of amino acids belonging to adjacent turn.
Question 971 Mark
What is the major structural polysaccharide in higher plants?
Answer
View full question & answer→Cellulose.