1. Chemistry of Life

2. Chemistry of Life I. Nature of Matter A. Atoms B. Chemical Bonding
II. Water and Solutions
A. Cohesion & Adhesion
B. Polarity
C. Acid & Bases

3. More Chemistry…. Chemistry of Cells A. Carbohydrates B. Lipids
C. Proteins
D. Nucleic Acids
Energy and Chemical Reactions
A. Energy
B. Enzymes

4. Atoms
Smallest unit of matter that cannot be broken down by chemical means.
Protons – (+)
Neutrons – (0)
Electrons – (-)

5. Element v. Compound Element – one kind of atom
Compound – two or more different elements

6. Periodic Table…..

7. Bonding….
Covalent: share electrons
Shells….

8. More bonding… Hydrogen: occurs between polar molecules
Water is a polar molecule: opposite ends of the molecule have opposite charges

9. Even more bonding…
Ionic: gaining or losing electrons; become charged and…we know…opposites attract!

10. Recap… http://www.youtube.com/watch?v=QqjcCvzWwww

11. Cohesion, Adhesion, and Surface Tension
Cohesion: molecules attracted to each other – causes surface tension
Adhesion: molecules
attracted to others – end
up with capillary action.
Cohesion and adhesion responsible for Giant Redwoods

13. Aqueous Solutions
Solution: mixture where one or more substances are evenly distributed in another substance.
Ex. Salt dissolves in water
Polarity: polar easily
dissolves in water;
nonpolar does not dissolve well in water (oil
and water)

14. Acids and Bases
When a hydrogen is stripped away from a covalent bond it leaves as an ion H+ (called a hydrogen ion), if it is stripped from a water molecule it leaves OH- a hydroxide ion
Covalent bonds of water often break spontaneously-ionization
H2O → H OH-

15. pH Scale
Changes in acidity (or basicity) due to an increase or decrease in hydrogen ions are measured with the pH scale
pH scale is used to determine the acidic or basic nature of a solution compared to pure water
Pure water has an equal concentration of hydrogen and hydroxide ions pH = 7

17. Chemistry of Cells
Organic compounds are found in living things – contain carbon and are covalently bonded.
Four types: carbohydrates, lipids, protein, and nucleic acids.

18. Organics…
Carbohydrates: C, H, O 1:2:1 (ex. Glucose – source of energy)
Lipids: aka fats – nonpolar (remember the oil and water)… stores energy
Proteins: chains of amino acids
Nucleic acids: store and transmit heredity information – DNA, RNA
ATP is the main source of energy in a cell.

19. Enzymes
Starting a chemical reaction requires activation energy (energy to start “activate”).
Enzymes speed up reactions by lowering activation energy.

20. More enzymes…
Enzymes bind only certain substrates (in other words…they are picky!)
pH and temperature affect enzyme activity…
HOW?