Class 11 Biology — Chapter 9: BIOMOLECULES
Chapter 9: BIOMOLECULES is a chapter in Class 11 Biology (NCERT), part of the CBSE NCERT curriculum followed by over 25 million students across India. This chapter covers 6 topics including Chemical Analysis of Living Tissues, Amino Acids: Structure and Classification, Simple Lipids: Fatty Acids and Glycerol. BrainWeave provides free AI-powered explanations — by voice or text, in Hindi or English — with no signup required.
What you'll learn
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▸Chemical Analysis of Living Tissuestrichloroacetic acidacid-soluble poolacid-insoluble fractionash analysisfiltrate
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▸Amino Acids: Structure and ClassificationCore conceptα-amino acidR groupzwitterionproteinaceousglycine
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▸Simple Lipids: Fatty Acids and GlycerolCore conceptlipidsfatty acidglycerolsaturatedunsaturated
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▸Complex Lipids: Triglycerides and PhospholipidsCore concepttriglycerideesterifiedphospholipidlecithinfats and oils
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▸Nitrogenous Bases, Nucleosides, and NucleotidesCore conceptnitrogenous basesnucleosidenucleotideadenylic acidgenetic material
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▸Introduction to Carbohydrates (Sugars)Core conceptcarbohydratessugarsglucoseribosemonosaccharide
Chapter Summary
Understand the experimental methods to separate biomolecules from living tissues, including the use of trichloroacetic acid to obtain an acid-soluble pool (filtrate) and an acid-insoluble fraction (retentate). Also, understand how burning tissue to ash helps identify inorganic constituents.
Identify the fundamental structure of an α-amino acid, which includes a central carbon, an amino group, a carboxyl group, and a variable 'R' group. Understand how they are classified as acidic, basic, or neutral based on the R group, and learn about their zwitterionic form in solution.
Describe the structure of simple lipids, focusing on fatty acids (a carboxyl group attached to an R group) and glycerol (trihydroxy propane). Differentiate between saturated fatty acids (no double bonds) and unsaturated fatty acids (one or more double bonds).
Understand how fatty acids are esterified with glycerol to form complex lipids such as monoglycerides, diglycerides, and triglycerides (fats and oils). Describe the structure of phospholipids, like lecithin, which contain a phosphate group and are crucial components of cell membranes.
Identify the building blocks of nucleic acids. Differentiate between nitrogenous bases (adenine, guanine, cytosine, uracil, thymine), nucleosides (base + sugar), and nucleotides (base + sugar + phosphate group).
Recognize carbohydrates as a major class of biomolecules and identify the basic structures of common monosaccharides such as glucose (a six-carbon sugar) and ribose (a five-carbon sugar).
Practice Questions from this Chapter
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- Identify the main types of biomolecules? Get Solution →
- Unravel the secret of protein shapes? Get Solution →
- Discover how cells use different lipids? Get Solution →
- What chemical is used to grind a living tissue in order to perform a chemical analysis for organic compounds? Get Solution →
- The fraction obtained from chemical analysis that is acid-soluble is also known as what? Get Solution →
- Compared to the Earth's crust, what two elements have a higher relative abundance in living organisms? Get Solution →
- What is the term for the remaining substance after a living tissue is fully burnt, which contains inorganic elements? Get Solution →
- How many types of amino acids are mentioned to occur in proteins? Get Solution →
Did you know?
- 💡 Spider silk, a protein, is stronger than steel by weight.
- 💡 Your brain is about 60% fat, making it the body's fattiest organ.
- 💡 Humans cannot produce 9 essential amino acids; we must eat them.
- 💡 Every atom of carbon in your body originated from a star.
- 💡 Some fish prevent freezing using special antifreeze proteins in their blood.
Frequently Asked Questions
How many topics are covered in this chapter?
This chapter covers 6 key topics: Chemical Analysis of Living Tissues, Amino Acids: Structure and Classification, Simple Lipids: Fatty Acids and Glycerol, Complex Lipids: Triglycerides and Phospholipids, Nitrogenous Bases, Nucleosides, and Nucleotides, and more. The BrainWeave AI tutor explains each one with examples.
Is Chapter 9: BIOMOLECULES important for board exams?
Class 11 is a foundation year. Mastering this chapter now will help you build strong fundamentals for the higher classes.
Can I get NCERT solutions for this chapter in Hindi?
Yes. BrainWeave's AI tutor supports Hindi, English, and Hinglish for both voice and text chat. Just ask your question in your preferred language.
Is BrainWeave free for Class 11 - Science?
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Can I use voice chat for this chapter?
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