Question 1

Q1: What are macromolecules? Give examples.

Accepted Answer

Biomacromolecules are large, complex chemical compounds found in living organisms. They are polymers with high molecular weights, typically in the range of ten thousand daltons (Da) and above. They are found in the acid-insoluble fraction when a living tissue is chemically analysed. Based on the cha...

Question 2

Q10: 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...

Accepted Answer

This is a research-based question that requires gathering data from external sources, as the textbook chapter does not provide these specific quantitative figures. The chapter states that plant cell walls are made of cellulose and that paper is cellulosic, highlighting its abundance and importance....

Question 3

Q11: Describe the important properties of enzymes.

Accepted Answer

Enzymes are biological catalysts that accelerate the rate of chemical reactions in living organisms. Based on the chapter, their important properties are as follows: 1.  Proteinaceous Nature: Almost all enzymes are proteins. They have a complex three-dimensional tertiary structure which is crucial f...

Question 4

Q2: What is meant by tertiary structure of proteins?

Accepted Answer

The tertiary structure of a protein refers to its overall three-dimensional (3-D) shape. It is formed when the long polypeptide chain, which may already have secondary structures like helices, is folded upon itself, much like a hollow woolen ball. This folding is stabilized by various interactions b...

Question 5

Q3: Find and write down structures of 10 interesting small molecular weight biomolecules. Find if there is any industry which manufactures the compounds b...

Accepted Answer

The chapter describes several small molecular weight biomolecules (micromolecules). Here are the structures of 10 such compounds based on the information and diagrams in the text: 1.  Glucose (a sugar): A hexose monosaccharide.     Formula: $C_6H_{12}O_6$ 2.  Ribose (a sugar): A pentose monosacchari...

Question 6

Q4: Find out and make a list of proteins used as therapeutic agents. Find other applications of proteins (e.g., Cosmetics etc.)

Accepted Answer

Based on the provided chapter, we can identify some proteins with therapeutic applications from their functions listed in Table 9.5: 1.  Insulin: Listed as a hormone. It is widely used as a therapeutic agent to manage diabetes mellitus by regulating blood sugar levels. 2.  Antibody: Listed as fighti...

Question 7

Q5: Explain the composition of triglyceride.

Accepted Answer

A triglyceride is a type of lipid, commonly known as a fat or oil. Its composition is based on two types of building blocks: glycerol and fatty acids. 1.  Glycerol: A simple three-carbon molecule with three hydroxyl (–OH) groups. Its chemical name is trihydroxy propane. 2.  Fatty Acids: These are lo...

Question 8

Q6: Can you attempt building models of biomolecules using commercially available atomic models (Ball and Stick models).

Accepted Answer

Yes, building models of biomolecules using commercially available atomic model kits (ball and stick models) is a practical and effective way to understand their three-dimensional structure. Procedure: 1.  Assign Colors: Use the standard color code for atoms: black for Carbon (C), white for Hydrogen...

Question 9

Q7: Draw the structure of the amino acid, alanine.

Accepted Answer

Alanine is an α-amino acid. Its structure consists of a central carbon atom (the α-carbon) bonded to four different groups: 1.  An amino group ($-NH_2$) 2.  A carboxyl group ($-COOH$) 3.  A hydrogen atom ($-H$) 4.  A variable R group, which for alanine is a methyl group ($-CH_3$) The structure is as...

Question 10

Q8: What are gums made of? Is Fevicol different?

Accepted Answer

According to Table 9.3 in the chapter, gums are classified as 'Polymeric substances' and are examples of secondary metabolites found in plants. Composition of Gums: Gums are natural complex polysaccharides. Polysaccharides are long chains of monosaccharide units. Therefore, gums are primarily compos...

Question 11

Q9: Find out a qualitative test for proteins, fats and oils, amino acids and test any fruit juice, saliva, sweat and urine for them.

Accepted Answer

This question describes a practical laboratory activity. The textbook chapter focuses on the chemical composition and structure of biomolecules but does not detail the procedures for these qualitative tests. However, some common standard tests are:    Test for Proteins (Biuret Test): Add a few drops...

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