Cellular Respiration, enzymes, and pineapples! Say what?????

Enzymes Are a type of protein that acts as a catalyst. A catalyst is something that speeds up a reaction but is not used in the reaction. Enzymes lower the activation energy. Activation energy is the energy required to cause the reaction to happen. Some reactions in our body would take 2.3 BILLION YEARS to happen if the right enzyme were not present.

Enzymes cont… Enzymes must have the right shape to bind to the substrate. Heat can change the shape and therefore the enzyme can not bind to cause the reaction. Enzymes can only work within certain pH ranges. Some like acid and some like basic. Depends on the enzyme.

Denatured enzymes Means the enzyme shape has been changed and therefore will not work. Ways enzymes can be denatured: Heat pH -Another chemical binds to the active site (like sticking chewing gum in a door knob so the key does not work)

Essential Amino Acids There are 22 amino acids but we can only make about half of them ourselves. The others must be obtained from our food. These are called essential amino acids. Vegetarians must be especially careful to include them in their diet.

Pineapple Lab Results Fresh pineapple has bromelain, an enzyme that breaks down proteins. Gelatin is a protein. Canned pineapple has been “cooked” before it is canned. The heat denatured bromelain. Apple cider vinegar is acidic. Acid denatured the bromelain. Meat tenderizer breaks down protein.

Cellular respiration has 3 main steps Glycolysis is the first step. Glycolysis is breaking glucose in half. The resulting chemicals are called pyruvates. So….Glucose split in half results in 2 pyruvates. THIS STEP REQUIRES 20 DIFFERENT ENZYMES!

Cellular Respiration overview Step 1 Step 2 Step 3

Glycolysis The breaking down of glucose.

Conclusion Questions: Why would cooking some foods not be as nutritious/ beneficial to us as eating steamed or fresh foods? Why should we not add fresh pineapple or kiwi fruit to gelatin when making desserts? Why do you think fatigue is a symptom for people lacking digestive enzymes? Is it natural for our bodies to produce fewer enzymes as we get older? How could food help people who are lacking digestive enzymes?