Name:______________________
A STUDY OF VARIOUS CELL TYPES
The purpose of this lab is to examine various types of cells and become familiar with the structures
located in the cytoplasm. You will be making slides of several plant cells and one animal cell. Follow
the directions carefully. Make your drawings large, in pencil, and according to the teacher’s directions.
For each cell type, determine the cell size according to the following scale dimensions: *Some
textbook use/research may be needed to answer all questions
Diameter of 40X field of view
=
4500µm
Diameter of 100X field of view
=
1800µm
Diameter of 400X field of view
=
450µm
Estimate the number of cells that would span the field of view. Divide the appropriate dimension by that
number for approximate individual cell size.
*For each cell drawing, include the individual cell size and the magnification used for viewing.
PART 1- Study of an Onion Cell
Cut a small piece of onion. Peel the skin from the inner surface. This transparent paper-thin layer is the
epidermis and is one cell layer thick. Make a wet mount slide of the tissue. Be sure it is flat. Examine the
cells under 100X (low power) and 400X (high power).
1. What is the shape of the cell?
______________________________________________________________________________
______________________________________________________________________________
2. What color is the cytoplasm?
______________________________________________________________________________
______________________________________________________________________________
3. Do you see any movement inside the cell?
_____________________________________________________________________________
______________________________________________________________________________
Take the slide to the lab station. Remove the cover slip and add a drop of the Lugol’s iodine solution.
Wait about 30 seconds for the stain to take effect, replace the cover slip and examine under the
microscope.
4. What effect does this have on the cells?____________________________________________
5. What is the advantage of using iodine?____________________________________________
Find the cell walls. They resemble “lines” forming the network between the individual cells and are
composed chiefly of cellulose. The cell wall surrounds the cell/plasma membrane. Inside the membrane
is the cytoplasm.
6. What are cell walls composed of?________________________________________________
7. What do we call the fluid that fills most of the cell?__________________________________
Locate the nucleus. It appears as a rounded body in the cytoplasm. It is surrounded by the nuclear
membrane. Inside the nucleus, you may see one or several smaller round structures. Each one of these is
called a nucleolus.
8. Are the nuclei always in the center of the cell?______________________________________
In the space provided, draw a group of 4 or 5 onion cells. Make each cell about an inch long and half an
inch wide so that you can label the parts clearly. Label: Cell wall; cell membrane; cytoplasm; nucleus.
You need only label each part one time. Label magnification level and size.
Also draw the nucleus of one of the cells enlarged to the size of a quarter. Label: Nuclear membrane;
nucleoplasm (cytoplasm in the nucleus); and the nucleolus.
4-5 Cells (Onion Cell Drawings); Enlarged Nucleus drawing
Mag:_______________Av. Cell Size:______________(Use the chart on front/#across diameter)
PART II: Cells of Elodea Leaf
Elodea is a freshwater plant often used in aquariums. Its cells appear green because they contain a
pigment called chlorophyll. By the process of photosynthesis, this pigment enables the plant to make its
own food.
Remove a young leaf from the tip of an elodea plant. Make a wet mount slide of the entire leaf. It will be
several layers thick. Locate the cytoplasm, cell wall, and chloroplasts (small, round green structures).
1. What evidence can you offer that you are looking at more than one layer of cells?
2. What structures are present in these leaf cells that were not in the onion cells?
3. What special function can the cells of green plants carry out?___________________________
Draw one cell from the elodea plant. Make it about 2 inches long. Label: Cell wall; cytoplasm;
chloroplast; and color the chloroplast green.
Elodea Cell Drawing
Mag:_______________Av. Cell Size:______________(Use the chart on front/#across diameter)
PART III: Cells of the Potato
Shave a very thin piece of potato off the pieces provided. Make it as thin as possible so that light can
pass through. Make a wet mount slide and add a drop of iodine. Examine an area where the cells are
clearly visible-usually an area near the edge. Use low power (100X).
Locate the structures that are stained dark blue. These are the starch grains stored in the cell. Draw a
group of ~3 cells, each about ½ ″ in diameter. Label: Cell wall, starch grain. Color the starch grains blue.
3 Cells (Potato Cells)
Mag:____________ Av. Cell Size:__________________
PART IV: Cells of Tomato Skin and Pulp
Cut a small piece of skin from the tomato, scraping the pulp from it. Make a wet mount slide of this so
that the shiny side faces you. Examine under low power. There are very small yellowish-red structures
in the cytoplasm that give the tomato its red color. These are called chromoplasts.
1. Are the cells tightly or loosely packed together?____________________________
*You do not need to draw these cells, but estimate their cell size. Mag:
Av Cell Size:
Put a small piece of tomato pulp on a slide in a drop of water and tear it apart with dissecting needles.
Look at it under low power. The cells are very large and thin walled.
Are there as many chromoplasts as in the skin?
*You do not need to draw these cells, but estimate their cell size. Mag:
Av Cell Size:
PART V: Human Cheek Cells
Gently scrape the inside of your mouth with a clean toothpick. Smear the material on a slide. Add one
drop of water and one drop of Methylene Blue Stain and allow it to stain about 30 seconds. Throw the
toothpick away. Now examine the slide under low and high power.
1. What structures do the cheek cells have in common with the onion and elodea cells?
2. What structure is missing that was present in the onion and elodea cells?__________________
3. What structure was stained the darkest by the Methylene Blue Stain?____________________
Draw several cells. Remember to make the cells large. Color them the way they appear. Label: Cell
membrane; cytoplasm; and nucleus.
Mag:_________________ Av. Cell Size:___________________
NAME:
Microscope Cell Lab (Plant and Animal Cells)
DATE:
*Please use your textbook/research where needed
1. Compare and contrast similarities and differences between plant and animal cells. (chart form)
2. What are the advantages of plant cells having cell walls?
3. Why do animal cells lack cell walls?
4. What was the purpose of using stain (iodine and methylene blue)?
5. What cell types were packed together tightly, the tomato pulp cells or the tomato skin cells?
What function or purpose do all of these tightly packed cells serve?
6. Which cells had chloroplasts present?
7. What function do they serve? Why is this important?
8. Which cells had large, oval structures called starch granules?
9. What function do they serve?
10. If potatoes and onions are considered plants, then why were there no chloroplasts present?
11. Which cells had chromoplasts present?
12. What are chromoplasts? What function do they serve? Why is this important?