{"id":120209,"date":"2022-05-09T15:37:10","date_gmt":"2022-05-09T10:07:10","guid":{"rendered":"https:\/\/www.mapsofindia.com\/my-india\/?p=120209"},"modified":"2022-05-09T15:37:10","modified_gmt":"2022-05-09T10:07:10","slug":"chapter-9-biomolecules-questions-and-answers-ncert-solutions-for-class-11-biology","status":"publish","type":"post","link":"https:\/\/www.mapsofindia.com\/my-india\/education\/chapter-9-biomolecules-questions-and-answers-ncert-solutions-for-class-11-biology","title":{"rendered":"Chapter 9 – Biomolecules Questions and Answers: NCERT Solutions for Class 11 Biology"},"content":{"rendered":"

1. What are macromolecules? Give examples.<\/h2>\n

Solution:
\nMacromolecules are the biomolecules that are formed by the polymerization of a huge number of micromolecules possessing higher molecular weight. Micromolecules are found in the colloidal state in the intercellular fluid due to their insoluble nature. Protein is a macromolecule.<\/h3>\n

2. Illustrate a glycosidic, peptide and a phospho-diester bond.<\/h2>\n

Solution:
\nGlycosidic bond \u2013 The bond between the individual monosaccharides is called a glycosidic linkage. This bond is formed between two carbon atoms of two adjacent monosaccharide units.<\/h3>\n

\"\"<\/p>\n

Peptide bond \u2013 It is a covalent bond. The amino acids in proteins are linked to one another through peptide bonds. It is formed between when the carboxyl group (-COOH) of one amino acid interacts with amino group (-NH2 ) of the adjacent amino acid when condensed.
\nFormation of Peptide bond \u2013 Example<\/h3>\n

\"\"<\/p>\n

Phospho-diester bond \u2013 that joins successive sugar molecules in a polynucleotide. It is a strong covalent bond formed between two adjacent sugar groups and phosphate. These are the bonds that form the sugar-phosphate backbone of the nucleic acids<\/h3>\n

\"\"<\/p>\n

3. What is meant by tertiary structure of proteins?<\/h2>\n

Solution:
\nIt is a structure that forms when the secondary coiled polypeptides are folded to produce a hollow, wollen ball-like structure. It is folded such that the functional side groups appear on the surface while the inactive side groups are found inside.<\/h3>\n

\"\"<\/p>\n

4. Find and write down structures of 10 interesting small molecular weight biomolecules. Find if there is any industry which manufactures the compounds by isolation. Find out who are the buyers.<\/h2>\n

Solution:<\/h3>\n

\"\"<\/p>\n

\"\"<\/p>\n

\"\"<\/p>\n

Compound
\nManufacturer
\nBuyer
\nStarch
\nPremier starch products private limited
\nResearch institutes and laundries
\nLiquid Glucose
\nImperial liquid glucose
\nUsed in making flavored drink and in research
\nEnzymes like amylase, protease, and cellulase
\nPlanet Biotech India
\nUsed in research<\/h3>\n

5. Proteins have primary structure. If you are given a method to know which amino acid is at either of the two termini (ends) of a protein, can you connect this information to purity or homogeneity of a protein?<\/h2>\n

Solution:
\nPositional information of a protein is called the primary structure of the protein. The first amino acid in a protein is called N-terminal amino acid, and the last amino acid in a protein is called the C-terminal amino acid.
\nYes, we can connect this information to check the purity or homogeneity of a protein. On the basis of carboxyl and amino groups, amino acids can be acidic, basic and neutral. Proteins can be acidic, basic and neutral.<\/h3>\n

6. Find out and make a list of proteins used as therapeutic agents. Find other applications of proteins (e.g., Cosmetics etc.)<\/h2>\n

Solution:
\nFollowing are the list of proteins used as therapeutic agents.
\nInsulin, Oxytocin, Immunoglobin, Antidiuretic Hormone( ADH), Thrombin, Fibrinogen, Renin and streptokinases.
\nSome other applications are:
\nAre used as artificial sweeteners. Thaumatin is a low-calorie sweetener.
\nProteins are used as dietary supplements to maintain health
\nThey are used in creams and shampoos<\/h3>\n

7. Explain the composition of triglyceride.<\/h2>\n

Solution:
\nWhen glycerol combines with three fatty acids on each of the OH groups through ester bonds, it is known as triglyceride.<\/h3>\n

\"\"<\/p>\n

All the three fatty acids of triglyceride in pure fat are similar while in mixed fat, they are dissimilar.<\/h3>\n

8. Can you describe what happens when milk is converted into curd or yoghurt, from your understanding of proteins<\/h2>\n

Solution:
\nDuring fermentation, milk protein such as casein is denatured which transforms globular proteins into fibrous proteins. This change is responsible for the production of curd or yoghurt.<\/h3>\n

9. Can you attempt building models of biomolecules using commercially available atomic models (Ball and Stick models).<\/h2>\n

Solution:
\nYes, Biomolecules can be represented by ball and stick model. Here bonds which hold the molecule are
\nindicated by sticks while the atoms are represented by balls.
\nThe figure below is a model of D-glucose where atoms of hydrogen are indicated by green balls, oxygen atoms are represented by pink balls and carbon atoms are represented by grey balls.<\/h3>\n

\"\"<\/p>\n

10. Attempt titrating an amino acid against a weak base and discover the number of dissociating
\n(ionizable) functional groups in the amino acid.<\/h2>\n

Solution:
\nThe pH of the amino acid is recorded, and the weak base is slowly supplemented to the amino acids while continuously noting the pH. The number of changes recorded indicates the number of ionisable functional groups \u2013COOH in the acidic range and \u2013NH2in the alkaline range.<\/h3>\n

11. Draw the structure of the amino acid, alanine.<\/h2>\n

Solution:
\nThe structure of Alanine is as follows:<\/h3>\n

\"\"<\/p>\n

12. What are gums made of? Is Fevicol different?<\/h2>\n

Solution:
\nGums are heteropolysaccharides formed by different monosaccharide units associated by glycosidic bonds. On
\nthe other hand, fevicol is different from gums as it is made up of synthetic polymers.<\/h3>\n

13. Find out a qualitative test for proteins, fats and oils, amino acids and test any fruit juice, saliva, sweat and urine for them.<\/h2>\n

Solution:
\nQualitative test for proteins
\nBiuret test: Biuret test identifies the presence of proteins by turning the colour of the solution to light blue to purple.
\nQualitative test for fats and oils
\nGrease test for oils: Certain oils give a translucent stain on blue paper. This test can be used to detect the presence of oils and fats.
\nQualitative test for amino acids
\nNinhydrin test:
\nUpon adding ninhydrin reagent to the solution, colour of the solution turns to pink, purple or blue based on the type of amino acid.
\nTest
\nName of item
\nProcedure
\nResult
\nConclusion
\nBiuret\u2019s test
\nFruit juice
\nJuice + biuret\u2019s reagent
\nChange of color from light blue to purple
\nPresence of protein<\/h3>\n

Saliva
\nSaliva + biuret\u2019s reagent
\nChange of color from light blue to purple
\nPresence of protein<\/h3>\n

Sweat
\nSweat + biuret\u2019s reagent
\nColour does not change
\nAbsence of protein<\/h3>\n

Urine
\nDrops of urine + biuret\u2019s reagent
\nChange of color from light blue to purple
\nPresence of protein
\nGrease test
\nFruit juice
\nFew drops of juice on brown paper
\nTranslucent spot not observed
\nAbsence of oils and fats<\/h3>\n

Saliva
\nFew drops of saliva on brown paper
\nTranslucent spot not observed
\nAbsence of oils and fats
\nSolubility test
\nSweat
\nWater added with sweat
\nOil presence
\nFats or oils can be present<\/h3>\n

Urine
\nWater added to a few drops of urine
\nSlight oily presence
\nFats may or may not be present
\nNinhydrin test
\nFruit juice
\nJuice+ninhydrin reagent (boil for few minutes)
\nChange of color from no color to purple, pink or blue
\nPresence of amino acids<\/h3>\n

Saliva
\nsaliva+ninhydrin reagent (boil for few minutes)
\nChange of color from no color to purple, pink or blue
\nPresence of amino acids<\/h3>\n

Sweat
\nsweat+ninhydrin reagent (boil for few minutes)
\nNo color change
\nAbsence of amino acids<\/h3>\n

Urine
\nurine+ninhydrin reagent (boil for few minutes)
\nDepending upon type of amino acid, colourless solution changes to purple, pink or blue color
\nPresence of amino acids<\/h3>\n

14. Find out how much cellulose is made by all the plants in the biosphere and compare it with how much of paper is manufactured by man and hence what is the consumption of plant material by man annually. What a loss of vegetation!<\/h2>\n

Solution:
\nBiosphere produces about 100 billion tonnes of cellulose out of 170 billion tonnes of total organic matter. Production of paper consumes about 0.5 billion tonnes of wood. Trees are also utilized for other purposes including food, medicines, timber, spices etc. An approximate estimate of 1.5 billion tonnes of food is required. Wood requirement for various purposes includes 2 billion tonnes. Therefore, it is difficult to gauge the annual consumption of plant material by man. Thus, the use of cellulose led to a great loss to the vegetation.<\/h3>\n

15. Describe the important properties of enzymes.<\/h2>\n

Solution:
\nAlmost all the enzymes are proteins. Important properties of enzymes are as follows:
\nThey have a higher molecular weight and are complex macromolecules
\nThey catalyse the biochemical reactions involved in the cell, assisting in breaking down larger molecules into simpler molecules or getting together two smaller molecules to form a larger one
\nEnzymes do not initiate but accelerate a reaction
\nThey affect the rate of biochemical reaction and do not influence the direction of the reaction
\nThey are action-specific
\nHigher turnover of enzymes causes an increase in the efficiency of a reaction. Most of the enzymes have high turnover number.
\nEnzymes are affected by temperature. As the temperature increases, enzymatic activity decreases. Maximum activity is observed at 30-40 degree Celsius.
\nMaximum activity is observed at 6-8 pH level
\nWith an increase in substrate concentration, the enzymatic velocity also increases reaching maximum velocity<\/h3>\n","protected":false},"excerpt":{"rendered":"

Class 11 Biology NCERT book solutions for Chapter 9 – Biomolecules Questions and Answers.<\/p>\n","protected":false},"author":21830,"featured_media":120091,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":{"0":"post-120209","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-education"},"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/120209","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/users\/21830"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/comments?post=120209"}],"version-history":[{"count":1,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/120209\/revisions"}],"predecessor-version":[{"id":120238,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/posts\/120209\/revisions\/120238"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/media\/120091"}],"wp:attachment":[{"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/media?parent=120209"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/categories?post=120209"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.mapsofindia.com\/my-india\/wp-json\/wp\/v2\/tags?post=120209"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}