1. Ch 2 The Chemistry of Life Students know most macromolecules (polysaccharides, nucleic acids, proteins, lipids) in cells and organisms are synthesized from a small collection of simple precursors. Students know enzymes are proteins that catalyze biochemical reactions without altering the reaction equilibrium and the activities of enzymes depend on the temperature, ionic conditions, and the pH of the surroundings.

2. The Nature of Matter Atoms Atoms –The basic unit of matter –The subatomic particles that make up atoms are protons, neutrons, and electrons. Elements Elements –A pure substance that consists entirely of one type of atom.

3. Chemical Compounds A substance formed by the chemical combination of two or more elements in definite proportions. A substance formed by the chemical combination of two or more elements in definite proportions.

4. Chemical Bonds Covalent Bonds Covalent Bonds –Form when electrons are shared by atoms. Ionic Bonds Ionic Bonds –Form when electrons are transferred from one atom to another.

5. Properties of Water A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms. A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms. Cohesion is an attraction between molecules of the same substance. Cohesion is an attraction between molecules of the same substance. –Water is extremely cohesive. Adhesion is an attraction between molecules of different substances. Adhesion is an attraction between molecules of different substances.

6. Solutions and Suspensions A mixture is a material composed of two or more elements or compounds that are physically mixed together but not chemically combined. A mixture is a material composed of two or more elements or compounds that are physically mixed together but not chemically combined. All the components of a solution are evenly distributed throughout the solution. All the components of a solution are evenly distributed throughout the solution. –Solute – the substance that is dissolved. –Solvent – the substance in which the solute dissolves

7. Acids, Bases, and pH pH scale is a measurement system to indicate the concentration of H+ ions in a solution. pH scale is a measurement system to indicate the concentration of H+ ions in a solution. Acids Acids –Solutions containing higher concentrations of H+ ions than pure water and have pH values below 7. Bases (Alkaline) Bases (Alkaline) –Solutions containing lower concentrations of H+ ions than pure water and have pH values above 7.

8. Organic Compounds Organic compounds are compounds that contain carbon. Organic compounds are compounds that contain carbon. Carbon is special Carbon is special –Carbon atoms have four valence electrons. –Carbon can bond with many elements, including hydrogen, oxygen, phosphorus –Carbon can bond to other carbon atoms.

9. Macromolecules Carbohydrates Carbohydrates Lipids Lipids Nucleic Acids Nucleic Acids Proteins Proteins

10. Macromolecules

11. Carbohydrates Monosaccharides, Disaccharides, and Polysaccharides 1. Monosaccharides are simple sugars. Examples are Glucose and Fructose. 1. Monosaccharides are simple sugars. Examples are Glucose and Fructose. 2. Disaccharides contain two monosaccharides. Examples are sucrose and Lactose. 2. Disaccharides contain two monosaccharides. Examples are sucrose and Lactose. 3. Polysaccharides include Starch, Glycogen, Cellulose and Chitin. 3. Polysaccharides include Starch, Glycogen, Cellulose and Chitin.

12. Function of Carbohydrates Main source of energy Main source of energy Structural support Structural support

13. Carbohydrates

14. Lipids Fats and Oils Are Similar. Fats and Oils Are Similar. – Fats function in long-term energy storage in organisms. –WaxesThey form a protective covering that stops water loss in plants. Each fatty acid is a long hydrocarbon chain with a carboxyl (acid) group at one end. Each fatty acid is a long hydrocarbon chain with a carboxyl (acid) group at one end.

15. Lipids

16. Proteins Made of amino acids. Made of amino acids. Function Function –Enzymes are proteins that act as organic catalysts to speed chemical reactions within cells. –Regulate cell processes. –Form bones and muscles. –Help fight diseases.

18. Nucleic Acids Monomer – Nucleotides Monomer – Nucleotides Function – store and transmit hereditary (genetic) information. Function – store and transmit hereditary (genetic) information. Examples – DNA and RNA Examples – DNA and RNA

19. Enzyme Proteins that act as biological catalysts. Proteins that act as biological catalysts. Cells use enzymes to speed up chemical reactions that take place in cells. Cells use enzymes to speed up chemical reactions that take place in cells. 3 factors that affect the way an enzyme works: 3 factors that affect the way an enzyme works: –Temperature –pH –Concentration of substrate