YIJC [H2] CI1.2_Biomolecules (N) vf

JC1 BIOLOGY LECTURE NOTES 1 CORE IDEA 1: THE CELL AND BIOMOLECULES OF LIFE TOPIC 1.2: BIOMOLECULES Learning Outcomes You should be able to: (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) (knowledge of chemical formulae of specific R-groups of different amino acids is 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 (m) explain primary structure, secondary structure, tertiary structure and quaternary structure of proteins, and describe the types of bonds that hold the molecule in shape (hydrogen, ionic and disulfide bonds, and hydrophobic interactions) (n) explain the effects of temperature and pH on protein structure (o) describe the molecular structure of the following proteins and explain how the structure of each protein relates to the function it plays: i. haemoglobin (transport) ii. collagen (structural) iii. G-protein linked receptor (signalling) (knowledge of details of the number of amino acids and types of secondary structures present is not required) Textbooks and References Raven, P H, Johnson, G B, Mason, K A, Losos, J and Singer, S (2013) Biology (10th Edition) (McGraw-Hill) ISBN 007338307 Reece, J B, Urry, L A, Cain, M L, Wasserman, S A, Minorsky, P V and Jackson, R B (2011) Campbell Biology (10th Edition) (Pearson Higher Education) ISBN 0321739752 H2

1 1 INTRODUCTION Biomolecules are important components of cell structures, including membranes which are made up of phospholipids, cholesterol, carbohydrates and proteins. The different classes of biomolecules (carbohydrates, lipids, proteins and nucleic acids) function as molecular building blocks for macromolecules to be assembled. • In living organisms, large biological mo lecules can be classified into four major classes based on molecular structure: o Carbohydrates o Lipids o Proteins o Nucleic Acids (covered in Core Idea 2: Topic 2.1) • Carbohydrates, proteins and nucleic acids are polymers ( polys = many ). Polymers are long molecules made from smaller repeating units called monomers ( monos = single) in a process known as condensation. Prior Knowledge You should be able to: A. [syllabus 6093] list the chemical elements which make up • carbohydrates • fats • proteins B. describe and carry out tests for • starch (iodine in potassium iodide solution) • reducing sugars (Benedi