1. Biological Molecules Links to GCSE  Nutrition & balanced diet  Digestion  Bonding

2. State the functions of biological molecules in organisms. State the functions of biological molecules in organisms. Define metabolism. Define metabolism. Explain how atoms may be bonded to form molecules. Explain how atoms may be bonded to form molecules. © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

3. You are what you eat! Chemical group Role Carbohydrates Energy storage and supply, structure (in some organisms) Proteins Structure, transport, enzymes, antibodies, most hormones Lipids Membranes, energy supply, thermal insulation, protective layers/ padding, electrical insulation in neurones, some hormones Vitamins & minerals Form parts of some larger molecules and take part in some metabolic reactions, some act as co-enzymes or enzyme activators Nucleic acids Information molecules, carry instructions for life Water Takes part in many reactions, support in plants, solvent/ medium for most metabolic reactions, transport

4. Biological elements and compounds in the human body © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

5. The composition of biological molecules  Chemical element found in Biological molecules are:  Carbon  Hydrogen  Oxygen  Nitrogen  Some contain minerals-phosphorous, sulphur, magnesium, iron & iodine

6. Key definitions  Risk factor: increases your chance of developing a particular disease  Metabolism: the sum total of all the biochemical reactions taking place in the cells of an organism  Catabolic reactions: involve breaking larger organisms into smaller ones e.g. digestion  Anabolic reactions: involve building smaller molecules to make larger ones e.g. muscle growth  Organic chemistry: the study of chemical reactions that contain carbon

7. Carbon can make up to four possible bonds with other atoms - it has a valency of four, this means it can make a wide variety of chains and rings for example. © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

8. Types of bonds  Covalent: very strong bonds formed when electrons are shared between atoms to give new molecules  Ionic: electrostatic bonds formed between 2 atoms that are of opposite charge  Hydrogen: weak bond formed between 2 dipole molecules where the negative pole of a molecule is attracted to the another’s positive pole

9. Methane showing covalent bonding structure; carbon chains and hydrocarbon (butane) © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

10. Double bonds in ethene and carboxylic acid © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

11.  Ionic bonding in sodium chloride

12. Hydrogen bonds in water © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

13. Carbohydrates  Links to G.C.S.E   Structure of plant cells   Control of blood sugar   Bonding   Balanced diet & food tests

14. Name the monomers and polymers of carbohydrates. Name the monomers and polymers of carbohydrates. Describe the general features of condensation and hydrolysis reactions. Describe the general features of condensation and hydrolysis reactions. © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

15. Hydrolysis and condensation © Pearson Education Ltd 2008 This document may have been altered from the original Week 12

16. Describe the molecular structure of alpha-glucose as an example of a monosaccharide carbohydrate. Describe the molecular structure of alpha-glucose as an example of a monosaccharide carbohydrate. State the structural difference between α (alpha) and β (beta) glucose. State the structural difference between α (alpha) and β (beta) glucose. Describe the formation and breakage of glycosidic bonds in the synthesis and hydrolysis of a disaccharide. Describe the formation and breakage of glycosidic bonds in the synthesis and hydrolysis of a disaccharide. Explain how the structure of glucose relates to its function in living organisms. Explain how the structure of glucose relates to its function in living organisms. © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

17. Key definition: Carbohydrates  Make up a group of molecules containing carbon, hydrogen & oxygen in the ratio C n (H 2 O) n  For every carbon atom there is the equivalent of a water molecule also present.  They make up approximately 10% of the organic matter of a cell.  They act as:  An energy source e.g. glucose  An energy store e.g. starch  A structure e.g. cellulose

18. Monosaccharides  Contain between 3 and 6 carbons, triose (3), pentose (5), & hexose (6) sugars  They are all  Soluble  Sweet tasting  Crystal forming  The most common are hexoses, e.g. glucose & fructose or C 6 H 12 O 6

19. Chain and ring forms of glucose. In nature hexoses tend to occur in rings. © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

20. 2 forms of glucose  α glucose  β glucose

21. Alpha and beta glucose isomers (simplified) © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

22. How does the structure relate to the function of glucose?  OH groups means it dissolves in water  Contain a large number of bonds that can be broken (by hydrolysis reactions) to simple molecules to release energy  They can be bonded (by condensation reactions) together to form larger storage molecules e.g. starch or structural molecules e.g. cellulose  Versions of the molecule α/ β give structural variety

23. Making and breaking bonds © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

25. Describe the formation and breakage of glycosidic bonds in the synthesis and hydrolysis of a polysaccharide. Describe the formation and breakage of glycosidic bonds in the synthesis and hydrolysis of a polysaccharide. Compare and contrast the structure and functions of starch (amylose) and cellulose. Compare and contrast the structure and functions of starch (amylose) and cellulose. Describe the structure of glycogen. Describe the structure of glycogen. Explain how the structures of starch and glycogen relate to their functions in living organisms. Explain how the structures of starch and glycogen relate to their functions in living organisms. © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

26. 1,4-glycosidic bond  2 α glucose molecules bond together to form a disaccharide called maltose.  If this happens repeatedly (up to many thousands of times) a larger molecule called amylose is formed.  The bond always happens between carbon 1 of one molecule and carbon 4 of the next, so is often referred to as a 1,4-glycosidic bond  Sometimes these chains become branched (bonds between a glucose carbon 1 and a glucose carbon 6) which results in amylopectin  When similar but more numerous shorter chains form the result is glycogen which is more compact and has more ‘free ends’

27. Starch: Amylose & amylopectin

28. Glycogen

29. Subunit structure of amylose and glycogen © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

30. Compare and contrast the structure and functions of amylose and cellulose. Compare and contrast the structure and functions of amylose and cellulose. Explain how the structure of cellulose relates to its function in living organisms. Explain how the structure of cellulose relates to its function in living organisms. © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

31. Orientation of β-glucose and chain formation © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

32. Cellulose chain, microfibrils and macrofibril (fibre)‏ © Pearson Education Ltd 2008 This document may have been altered from the original Week 13

33. Other structural carbohydrates  Peptidoglycan (murein)

34.  Chitin