University:
Texas A&M University
Course:
BIOL 319 | Integrated Human Anatomy and Physiology I
Academic year:

2022
Views:

237

Pages:

6
Author:

Arielle Armstrong

Does Vitamin E Prevent Aging? To Do: ✓ Scientists make observations about what they see in the world around them. ✓ Today you are going to be the scientist and make observations about apple slices in the 4 petri dishes. ✓ The apple in the petri dish was subjected to one of four conditions: ✓untreated ✓coated with water ✓coated with oil ✓coated with vitamin E After treatment, look at the slice in each dish and then fill in the worksheet. WHAT IS SO SPECIAL ABOUT VITAMIN E? ✓ Vitamin E is a powerful antioxidant (= against oxidation). ✓ Antioxidants protect your cells against free radicals.* ✓ Free radicals can cause cell damage. *Free radicals are atoms or molecules in which there is an unpaired electron in the outer shell of electron orbits. Under these conditions, the molecule is very reactive chemically, because it binds so easily by sharing its electron with another another atom. An atom of oxygen is an example of a free radical. It has seven electrons in its outer orbit, whereas it should have eight. That is why it binds so readily with another oxygen atom, so that together they share one of the electrons, enabling both atoms to have eight electrons when they are bound as a molecule. You might think of this as an “attack” by the free radical on other molecule. Depending on the kind of molecule “attacked” by free radicals, the effect may be damaging to cells ✓ When you leave a sliced apple out, what happens to it? ✓ It turns brown, right? ✓ This is because iron-containing chemicals inside the apple react with oxygen in the air. ✓ This reaction is called oxidation. ✓ How do apple cells get exposed to oxygen? ✓ Apples are made up of millions of tiny cells. ✓ When you cut an apple, you damage the wall that protects each cell, and this exposes its contents to oxygen in the air. ✓ If vitamin E is an antioxidant what would you hypothesize about its ability to protect apple slices from oxidation? Name:____________ Date:____________ Period:____________ Data Recording Sheet 1. In each column write your observations (what do you see) for each petri dish. Apple + air Apple + water Apple + oil Apple + Vitamin E 2. In which treatment did the apple turn the brownest? 3. In which treatment did the apple look the lightest? 4. Did vitamin E protect the apple? Answer Key Data Recording Sheet 1. In each column write your observations (what do you see) for each petri dish. Apple + air Apple + water This is your control, it will likely be darker than the water or the Vit. E. It probably won’t be darker than the oil treatment. Comparable to the Vit. E or darker than the Vit. E but lighter than the air or oil treatment. Will be the brownest. Apple + oil Apple + Vitamin E Will be lighter than the air and water. Sometimes the water and Vit. E are comparable, it depends on the apple. 1. In which treatment did the apple turn the brownest? The apple + oil 2. In which treatment did the apple look the lightest? The apple + Vitamin E 3. Did vitamin E protect the apple? Yes