Don’t Be Cheeky! 1. Using a tooth pick, gently scrape the inside of your cheek. 2. Place the cells on to the slide. 3. Place one drop of iodine onto your specimen. 4. Place a cover slip over your specimen. 5. View your specimen under both low power (small objective) and high power (larger objective) and diagram what you see.

Step #1: Behave In Lab

Step 2: Your Cells are Quite Small We will be using microscopes to view these mini structures.

The Onion Cell

1. Get a thin slice using your finger tips. 2. Place the thin onion slice onto the slide. 3. Place one drop of iodine onto your specimen. 4. Place a cover slip over your specimen. 5. View your specimen under both low power and high power and diagram what you see.

Adding a drop of Iodine

Plasmolysis Prepare a slide with one fresh water seaweed (Elodea) leaf. Diagram what you see. Identify the chloroplasts (site of photosynthesis) and the cell wall. Do not use the iodine indicator for this lab. Add saltwater (Hypertonic solution) and describe what you see.

Plasmolysis with an onion cell

Plasmolysis

Go Banana’s: Go Green! Banana cells are also useful. Smear a little (less than the size of a sesame seed) on a glass slide. Rub the cells apart, then put in a drop of Iodine solution. Cover the glass slide with a cover-slip. These cells contain starch grains.

Three Banana Cells

Coming Soon: Cell Division Lab

Complete the entire lab packet. 1. Each person is responsible for turning in a completed lab packet. 2. You may work in groups of four. 3. When you are finished with your lab, please clean your slides for the next group and make sure you turn off the power source to your microscope.