The Basic Unit of Life: The Cell
NAME_______________________PER____
Introduction: The cell is the basic unit of structure and function in organisms. Everything that is alive is
composed of at least one cell. In this lab, you will look at several different cells and identify specialized
structures within the cells.
Materials:
Microscope
Slides
Coverslips
Razor
Toothpicks
Iodine
Water dropper
Cork
Onion
Prepared blood slide
Elodea
Part A:Cork Cells
Robert Hooke was a scientist who, in 1665, observed cork and named the box-like compartments inside the
cork “cells.”
 Using a razor, shave thin slivers of cork onto a microscope slide. Be very careful!
 Add one drop of water and a coverslip.
 Focus on low, medium, and high power and try to find cells.
 Draw the cells as they appear on high power. Label the cell wall on one of your cork cells.
Questions:
1. Is cork from a plant or animal? What proof do you have?
2. What is the function of a cell wall?
Part B: Cheek Cells
 Using the flat end of a toothpick, gently scrape the inside of your cheek. Scrape lightly- you won’t be
able to see anything on the toothpick.
 Rub the end of the toothpick you scraped on a blank slide.
 Add 1 drop of iodine and a coverslip to the slide.
 Examine areas of cells that are not clumped together.
 Focus on high power and draw the cells. Label the cell membrane and the cytoplasm on one of the cells.
Questions:
3. Why did you add iodine to the cheek cells?
4. What is the outermost structure of the cheek cell?
How is this different from a plant cell?
5. Why might the shape of a cheek cell be less
uniform (boxy) than the shape of a cork cell?
Part C: Onion Cell
 Using your fingernail, remove the inside membrane of a piece of onion.
 Lay the membrane on a slide perfectly flat, add 1 drop of iodine and a coverslip.
 Examine the cells under medium power and look for cells with dark dots in the center. The dot
is the nucleus.
 Focus on high power on the cells where you can see a nucleus and look for another dot inside the
nucleus. This structure is the nucleolus.

Draw 1 cell in detail, labeling the cell wall, nucleus, and nucleolus.
Questions:
6. What is the main function of the nucleus?
7. Does the nucleus have a membrane around it?
8. What is the main function of the nucleolus?
9. What is the scientific term for a cell with a nucleus?
Part D: Elodea Cells
 Elodea is the scientific name for a freshwater plant commonly used in Biology.
 Obtain one leaf from the Elodea plant.
 Add the leaf to a slide, add 1 drop of water and a coverslip.
 Examine the cells under low or medium power and try to find green, oval-shaped chloroplasts.
 Draw the cells under high power and label the chloroplasts and cell wall.
Questions:
10. What is the purpose of chloroplasts?
11. Why does this plant appear green?
Part E: Blood Cells
 Using the prepared slide, look at human blood. DO NOT TAKE ANY BLOOD FROM
YOURSELF!
 Focus on high power and draw the cells.
Questions:
12. What shape are blood cells?
13. Do blood cells have a cell wall?
Wrap- up Questions:
Check the box that applies to the correct cell type. You may check both boxes or no boxes.
Characteristic
Plant Cells
Animal Cells
14
Autotroph
15
Heterotroph
16
Cell wall
17
Cell membrane
18
Nucleus
19
Chloroplasts
20
Cytoplasm
21
Rectangular-shaped cells
22
Round or blob-shaped cells
23
Nucleolus
24
Eukaryotic cells
25
Prokaryotic cells