NCERT Solutions for Class 11 Biology Chapter 9 Biomolecules
NCERT Solutions for Class 11 Biology Chapter 9 Biomolecules covers the chemical composition of living tissues, structure and classification of carbohydrates, proteins, lipids, nucleic acids, and the concept of enzymes.
Overview of Topics & Subtopics (Click to Jump)
1. Biomacromolecules
Short Note:
• Carbohydrates: classified as monosaccharides (e.g., glucose), oligosaccharides (e.g., sucrose), and polysaccharides (e.g., starch, cellulose, glycogen) — primarily provide energy and structural support.
• Proteins: polymers of amino acids linked by peptide bonds; perform structural, enzymatic, transport, hormonal, and defence functions.
• Lipids: fats, oils, and phospholipids; primarily used for energy storage and forming cell membranes.
• Nucleic Acids: DNA and RNA, polymers of nucleotides, carry and express genetic information.
2. Structure of Proteins
Short Note:
• Protein structure is described at four levels: primary (linear sequence of amino acids), secondary (alpha helix or beta pleated sheet), tertiary (3D folding), and quaternary (arrangement of multiple polypeptide subunits).
3. Enzymes
Short Note:
• Enzymes are biological catalysts, mostly proteins, that speed up biochemical reactions without being consumed, by lowering the activation energy required.
• Enzyme activity is affected by factors such as temperature, pH, substrate concentration, and the presence of inhibitors or cofactors.
NCERT Textbook Exercise Questions
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