Monday, January 18, 1999
Announcements: There will be a review session tonight in 110 Wartick Lab.

Lecture notes:
 

Acids are substances that release hydrogen ions (H⁺) in solution.
Example: HCL becomes H⁺ and CL^-

Bases are substances that combine with H⁺ in solution or release OH^-.

Buffers combine with or release hydrogen ions in response to changes in pH.

pH is the measure of the hydrogen ion (H⁺) concentration of a solution.
* Human body pH level is 7.4

1. 100^oc liquid range.
2. Frozen state floats. (less dense)
3. High heat capacity.
4. High heat of vaporization.
5. High heat of fusion.
6. High surface tension.
7. Highly polar

How would visitors from outer space describe life on earth?
* "Carbon based units"
* "ugly bags of mostly water"

If we are 75%-85% water, why aren't we "mushy" like a water balloon?
* All of the water in our bodies is contained

93% of the ELEMENTS in our bodies are Carbon, Hydrogen, and Oxygen.

Even though oxygen is 65% of the weight of the body and carbon is 18%, carbon is still the most important structural element in the body.
* It forms the "core" of all classes of chemicals in the body.
* It has 4 available binding sites.
* It has the ability to bind with a wide variety of other elements.

Carbo = carbon (C)

Hydrate = water = H₂O

All pure carbohydrates have a ratio of 1 carbon atom to 2 hydrogen atoms to 1 oxygen atom (CH₂0)_n.

A single unit (monomer) of a carbohydrate is called a monosaccharide.
* Monosaccharides are also called simple carbohydrates or simple sugars.

Simple carbohydrates have between a 3 and 7 carbon backbone. There are over 200 known monosaccharides. Most have 3, 5, or 6 carbons in their backbones.

Glucose (6C) "blood" sugar

Fructose (6C) fruit sugar

Galactose (6C) part of lactose

Ribose (5C) RNA

Deoxyribose (5C) DNA

Common Disaccharides
(disaccharides are two monosaccharides bonded together by condensation)

Sucrose - table sugar
1 glucose, 1 fructose

Lactose - milk sugar
1 glucose, 1 galactose

Maltose - malt sugar (found in germinating seeds, breakdown product
2 glucose

(NOTE: all Disaccharides have 1 glucose)

Common Polysaccharides
(polysaccharides means many sugars)
(all common polysaccharides are polymers, which means many units of glucose)

STARCH - storage form of glucose in plants. The linkage between molecules is called an alpha linkage. We can digest
(break) this bond and use the glucose for energy.

GLYCOGEN - storage form of glucose in animals. It is highly branched.

CELLULOSE - structural form of glucose in cell wall of plants. The linkage is called a beta linkage. Humans and other animals cannot digest this bond. Some bacteria, fungi and protozoans can.

CHITIN - a polymer much like cellulose except that one OH group is changed to a nitrogen containing group.