Fall2011_Lab6

=LAB 6 - Digestion=

The first person to arrive gets a piece of gum. Then they have to fill up a vial with 10mL of saliva. This is the 'spitter' Next, someone needs to label beakers. This is the 'labeler' Then, someone needs to prepare the protein and cut up an egg into small sliver-pieces. This is the 'cutter' The fourth person needs to help the other. This is the 'gopher'. You will go-for whatever they need. --> Read the lab manual instructions for creating your different test tubes and follow the recipe. I will go around and make sure you know what's going on, but always read the manual. - the chemicals you need will be on the lab bench in the back.

OVERALL:
This lab will involve setting up three experiments of different solutions and observing the reactions that take place.
 * //Grading the experimental results on your worksheet//: I won't grade your results, but I will grade your interpretations of your results. If you understand the experimental setup and why you need the different chemicals in the different combinations, it will make interpretation much easier. Also, ask me and I will help.

MINI-LECTURE:
- Survival of an individual organism. All organisms need energy and nutrients. What is energy? What is a nutrient? Why do organisms need this stuff, anyway? All organisms need to get energy and nutrients in order to keep their internal cells from running out of energy. If their cells are 'happy', the organism is 'happy'. From where do organisms get energy? Heterotrophs, specifically, use the energy and nutrients that are available in the environment (sometimes by eating other organisms). - Enzymes. These biological machines help break down ingested food into energy and nutrients. What are enzymes? How do they work, in general. In a microscopic sense, what influences the actions of these biomolecular machines? - What is the hypothesis of the lab for the different experiments? What do we expect to see, knowing what we know about the enzymes we are using and the stuff that's in the different test tubes? What is a control? What kind of control do we use in the different experimental setups?

Enzyme action.
Enzymes are bio molecules. Imagine each atom in the molecule as a little magnet (this is an "ion" pronouced "eye-on"). Some of parts of the enzyme are strong magnets, and some have a 'north' or 'south' attraction. Like attracts like in magnets (north attracts north). Opposites repel. With this magnetic structure, an enzyme can attach to other atoms in other (food) molecules. When the enzyme and the molecule come in contact, the enzyme can use the magnetic force to break apart (digest) or join molecules (build muscle) together. We'll only think about this in terms of digestion, but it works in all biological processes.

Environmental affects.
Enzymes are affected by things like the temperature and the amount of ions in the environment. Ions in a liquid environment, such as your saliva or your stomach juice, create an acidic or basic (also called alkaline) enviroment. Acids and bases are another way to describe how the liquid can be 'charged' or not. This is described as pH.

Imagine tiny magnets in the enzyme. Now imagine there are other magnets floating around the liquid in which the enzymes is acting (such as in the blood or in some tissue cytoplasm). These external magnets can change how the magnets in the enzyme works. The same goes with temperature, as the temperature in the liquid changes (in the blood, or cytoplasm, or the stomach juice), the enzyme may or may not work as quickly, which can alter whether something happens in a couple of minutes or a couple of months. If this is a digestive enzyme, then there will be no significant digestion, since food exits your digestive track in a couple of days, and at a low temperature the enzyme would not work that fast.