RVHS 4. Lipids

River Valley High School 1 2025 JC1 H2 Biology Lecture Topic 4: Biomolecules of Life - Lipids River Valley High School 2025 JC1 H2 Biology Lecture Topic 4: Biomolecules of Life - Lipids Name: ( ) Class: 25J__ Date: References Title Authors Biology (9th Edition) Campbell and Reece Longman A-Level Course in Biology: Core Syllabus Volume 1 Hoh Biological Science 1. Organisms, Energy and Environment (3rd Edition) Taylor, Green, Stout and Soper Understanding Biology for Advanced Level (4th Edition) Toole and Toole H2 Biology Syllabus 9477 (2025) Candidates should be able to use the knowledge gained in the following section(s) in new situations or to solve related problems. Related Topics Concepts Biomolecules of Life and Cellular Transport The structure of carbohydrates, lipids and proteins and their roles in living organisms Transformation of Energy between the Environment and Organisms The need for energy in living organisms Learning Outcomes 1B. Biomolecules of Life and Cellular Transport g. Describe the structure and properties of the following monomers: i. α-glucose and β-glucose (in carbohydrates) ii. glycerol and fatty acids (in lipids) iii. amino acids (in proteins) (chemical formulae of specific R-groups of different amino acids are not required) h. Describe the formation and breakage of the following bonds: i. glycosidic bond ii. ester bond iii. peptide bond i. Describe the structures and properties of the following biomolecules and explain how these are related to their roles in living organisms: i. starch (including amylose and amylopectin) ii. cellulose iii. glycogen iv. triglyceride v. phospholipid For practical, candidates should be able to: • carry out the emulsion test for lipids.

River Valley High School 2 2025 JC1 H2 Biology Lecture Topic 4: Biomolecules of Life - Lipids Lecture Outline I. Importance of Lipids II. Nature of Lipids III. Fats IV. Phospholipids V. Glycolipid VI. Cholesterol I. Importance of Lipids Lipids are a heterogonous group of compounds inclusive of fats, oils, waxes, steroids and phospholipids. In general, l ipids perform three biological functions (although certain lipids apparently serve more than one purpose in some cells): 1. Lipids containing hydrocarbon chains serve as energy stores. 2. Lipid molecules in the form of lipid bilayers are essential components of biological m embranes. 3. Many intra- and intercellular signaling events involve lipid molecules. II. Nature of Lipids • Lipids are a group of organic compounds whose molecules contain atoms of carbon, hydrogen, and oxygen only. • General formula: No general formula but t he ratio of hydrogen atoms to oxygen atoms is always much greater than 2:1. For example, tristearin: C57H110O6. • Structure-Property Relationship: o Although lipids are not polymers, they are large molecules assembled from smaller molecules by condens