1. Inorganic Compounds

2. Inorganic Compounds Usually small Lack carbon and/or hydrogen
Many contain ionic bonds
Examples:
Water, oxygen, carbon dioxide, many acids, bases and salts

3. Water The most abundant inorganic substance in the human organism
Makes up about 60% of body weight
Makes up most of the volume of cells and body fluids

4. Properties of Water Excellent solvent and suspending medium…huh?
It dissolves a lot of different things
Solvent – a liquid or gas in which some other gas is suspended
Solute – the material that is suspended in a solvent
Solution – combination of a solvent and solute
Water caries nutrients, oxygen, and wastes as well as suspends large organic molecules allowing for essential chemical reations to take place.

5. Water can participate in chemical reactions
In decomposition water helps break down large molecules. (hydrolysis)
Helps in the synthesis of hormones, enzymes, proteins, lipids and carbohydrates

6. Water absorbs and releases heat very slowly
Water requires a large input of energy to increase its temperature and a large release of energy to decrease its temperature
The large amount of water in the body helps to maintain a constant temperature

7. Water requires a large amount of heat to change from a liquid to a gas
When you sweat it takes a lot of energy to evaporate.

8. Water serves as a lubricant
As a major part of mucus, saliva and other body fluids, water allows internal organs to slide over each other and lubricates joints where bones, ligaments and tendons rub against each other

9. Acids, Bases and Salts Combination of Ions
Dissociation/Ionization – when an ionic substance dissolves in water and breaks apart into the ions that formed it
Acids dissociate into H+ ions
Bases dissociate into OH- ions
Salts form ions that are not H+ or OH-

10. Acids and Salts react with each other to form salts:
HCl + KOH  KCl + H2O

11. Acid/Base Balance
The more H+ in a solution the more acidic something is
pH is the measure of how acid something is

12. pH Scale
Runs from 0 – 14
Based on the amount of H+ dissolved in solution
0 = lots of H+ therefore acidic
14 = lots of OH- therefore basic (alkaline)
7 means the amount of H+ = OH- (neutral)
A change of 1 on the pH scale means a 10x change in concentration

13. Body’s pH
The pH range of blood is (you need to know these exact numbers!)
The body maintains pH through the use of buffer systems

14. Buffer Systems
Consist of a weak acid and a weak base that function to prevent drastic changes in the pH of body fluid by rapidly changing strong acids and bases into weak acids and bases

15. Negative Feedback and pH balance
Decreased blood pH  detected by chemoreceptors in the body  control center in the brain sends nerve impulses to the respiratory system  diaphragm contracts more forcefully to get rid of more CO2  increase in pH