9/23/11

Today in class, we picked up where we left off in our yellow notes packet (from "What is an ENZYME?"). Some key vocabulary as defined in the packet:

1. Enzyme: specialized proteins which function as catalysts
2. Catalysts: speed up the rate of a chemical reaction without being used up itself (it is reused, or recycled)
3. Activation Energy: the amount of energy needed to stimulate the reactants to react in a chemical reaction.
   
4. pH: (potential hydrogen) the measurement of how acidic or basic a liquid solution is
5. Ion: a charged particle that has either gained or lost an electron
6. Acids: chemical compounds that give H+ ions to solutions
7. Bases: compounds that accept H+ ions and remove them from a solution
8. Neutral: a solution in which the concentration of H+ and OH- ions are equal
9. Substrate: a specific molecule that an enzyme recognizes to bind with

And then important ideas we discussed in class (also from the yellow notes packet):

• Protein Structure:

a. Primary Structure:

a SPECIFIC sequence of amino acids (any slight change could cause the protein to

not function properly)

b. Secondary Structure:

Held together by hydrogen bonds along the backbone (an alpha helix/pleated sheet)

c. Tertiary Structure:

Held together by chemical bonds between the side groups (3D in shape)

d. Quaternary Structure:

protein that consists of 2 or more polypeptide chains + the bonding of these chains

• Proteins are polymers of amino acid monomers
• Types of proteins= structural, storage, contractile, transport, defensive, signal, enzymes (important for our bodies to function)

• Ways to speed up a chemical reaction:
  

1. heat mixture in a lab (however, not for cells--too much heat may result in the shutting down of cells)
2. decrease in activation energy:

the enzyme binds to the reactant molecules making it easier to break their bonds

• Enzymes are affected by:
• temperature
• pH
• concentration
• specificity

Homework:

• UP p. 7-18 ("Enzymes are Everywhere" lab)
• Extra Credit Sheet
• Internet Biochemistry Tutorial p. 4 (for review)... Site on p. 5, #3 under "More Internet Activities"

Also, we got our Chapter 18 and 19 quiz back. Be sure to prepare for Monday's "Enzymes are Everywhere" lab!

Next Scribe: Michael