Chemistry of life

1. Chemistry of life Chapter 2

2. Lesson 1 Basic Chemistry

3. DO NOW • Define, in your own words: • Atom • Element • Proton • Neutron • Electron

4. Elements and Atoms • All matter is made up of substances called elements. • Only 92 naturally occurring elements • Body is composed of only a few elements • Carbon • Nitrogen • Oxygen • Hydrogen • Phosphorous • Calcium • Atoms – smallest unit of an element • Made up of: • Protons – + charge, nucleus of atom • Neutrons – 0 charge, nucleus of atom • Electrons – ( - ) charge, orbit around nucleus

5. Isotopes • Same element differs in the number of neutrons in the nucleus and weight. • Carbon has 2 common isotopes • Carbon-13 and Carbon-14

6. Radioactive Isotopes • As isotopes break down they release energy in the form of rays and subatomic particles • Carbon-14 is a common Radioactive isotope • Unstable and breaks down over time http://science.howstuffworks.com/environmental/earth/geology/carbon-14.htm

7. Molecules and Compounds Molecule – 2 or more of the same atoms bonded together to form a chemical unit Compound – 2 or more different atoms bonded together to form a chemical unit. Types of Bonds: Ionic – created by an electrical attraction Covalent – sharing of electrons

8. Bonds

9. Bonds Chemical Bonds • Polar Covalent – electrons spend more time with the more electronegative element • Non-polar Covalent – equally shared electrons

10. In class assignment • Elements in Living Things Coloring Handout

11. Homework • Study Questions pg 39 # 1-4

12. Lesson 2 Water, Acids and Bases

13. Do Now • What is the difference between ionic and covalent bonds? • What elements make up the human body?

14. Organic vs Inorganic • Organic Molecules – contain carbon • Carbohydrates, proteins, lipids • Inorganic Molecules – do not contain carbon • Most important molecule is WATER

15. Water • Polarity and Hydrogen bonding gives water all of it’s unique and beneficial properties. • Solvent for polar molecules • Cohesive – water molecules stick together • Adhesive – water molecules stick to other surfaces • High Specific Heat Capacity/Heat of vaporization Video

16. Acids and Bases • Acids – substance that separates in water • Bases – takes up hydrogen ions or releases hydroxide ions • pH scale – ranges from 0-14, indicates the acidity and basicity of solutions pH scale Acids and bases

17. Content Check • Depending on what you’ve eaten recently, the pH of your urine can vary from 5 to 8. • Which is more acidic – urine at pH 5 of pH 8

18. Homework • Study Guide Questions pg 39 # 6-7

19. Lesson 3 Molecules of Life

20. Do Now • Name the 4 important molecules of life Macromolecules

21. Molecules of Life

22. Molecules of Life • ^ Dehydration Synthesis • remove water, make bigger molecules • < Hydrolysis – add water, break down molecules

23. Carbohydratesquick, short-term cellular energy • Monosaccharide – one carbon ring. Ex: Glucose, Fructose • Dissaccharide – two carbon rings. Ex: sucrose • Polysaccharide – three or more carbon rings. Ex: starch, cellulose

24. Carbohydrates • Made up of C, H, O in a 1:2:1 ratio • Glucose – used as an immediate source of energy • Maltose is 2 glucose molecules, found in alcoholic beverages • Sucrose – glucose & fructose together, this is table sugar • Lactose – glucose and galactose, this is found in milk

25. Polysaccharides • Means many sugars, LONG chains of sugar molecules • Starch – energy storage in plants • Glycogen – energy storage in animals • Cellulose – what cell walls are made up of • We cannot digest this, this helps to scrape the walls of our intestines

26. Common Polysaccharides

27. Lipidslong-term energy storage, part of membranes Saturated Fats - have only single covalent bonds, solid at room temperature. Ex: Butter (usually of animal origin) Unsaturated Fats – have double/triple bonds, liquid at room temperature. Ex: Oils (usually of plant origin)

28. Lipids Made of a glycerol molecule and a triglyceride, or three fatty acids. Can be emulsified – mixed with water, molecules position themselves around a droplet so that their nonpolar ends stick out and the droplet disperse in water Phospholipids – contain phosphate group, important for cell membranes Steroids – different structure than fats, back bone of 4 carbon rings, with differing side chains cholesterol is an example of a steroid

29. Proteinswide range of functions • Macromolecules made up of 20 different Amino Acids • Amino acids are arranged as follows • Central carbon atom • An amino group • An R Group

30. Structure of Proteins • Composed of amino acids • When two amino acids join, called a dipeptide • Polypeptide contains 3 or more amino acids • Primary Structure • Sequence of Amino acids in a polypeptide • Secondary Structure • Coiling or folding of the protein • Tertiary Structure • Hydrogen, ionic, covalent bonding all occur in polypeptides • Quaternary Structure • Protein that has more than 1 polypeptide, arrangement of individual polypeptides • When proteins are exposed to extreme heat and pH they denature, and this is irreversible

31. Protein Structure

32. Content Check • The sequence of amino acids found in a protein is that protein’s __________ structure a. primary b. secondary c. tertiary d. quaternary

33. Enzymes • Protein catalysts • Enable particular metabolic reaction to occur at the body’s normal temperature • Energy activation – energy needed to start a reaction • Substrates – reactants in an enzymatic reaction • Enzymes are very specific this is caused by the shape and chemical composition of it’s active site.

34. Enzyme Substrate Complex

35. Nucleic Acidscontain hereditary information • Two Classes: • RNA – ribonucleic acid, bases are AUGC • DNA – deoxyribonucleic acid, bases are ATGC

36. Nucleic Acids

37. ATP • Adenosine plus 3 phosphate groups • PRIMARY ENERGY CARRIER IN CELLS • Cells require a constant supply  continually break down glucose • Some uses: • Synthesizing macromolecules • Muscle contraction • Conduction of nerve signals

38. In Class Assignment/Homework • Macromolecules Worksheet #2 • Study Questions # 9,10,11,12,15,18