PART A: Plant Cells ( Onion Skin Wet Mount)
1. Peel the delicate transparent tissue from the
inner surface of a piece of onion using forceps (tweezers).
2. Make a wet mount by placing the tissue,
unwrinkled, in a small drop of water on a glass slide.
3. Add one small drop of iodine stain to
the tissue and cover with a cover slip as directed. (* be careful - the iodine
can stain your clothes!)
4. Examine the onion cells at low power, focus as
necessary.
5. Next examine the cells under HPO.
6. Prepare a diagram of onion skin tissue showing
three to four cells. Label the structures you can
identify from the microscope. (examples - cell membrane, nucleus, etc.)
Answer the following questions:
1. Describe the shape of the cells.
___________________________________________
2. What cell structures and organelles can you
see? ______________________________
3. How come there are no chloroplasts evident?
________________________________
PART B. Hydrilla Frond
1. Place a small piece of hydrilla frond on a clean glass slide with a cover slip.
2. Focus under LPO and HPO. Observe the greenish rounded bodies in the cytoplasm of each cell. Draw and label the parts.
Answer the following questions:
1.What are the greenish rounded bodies inside the cells?
2. What is the movement of the greenish rounded bodies inside the cell?
3. What does the movement of the greenish rounded bodies indicate?
PART C: Animal Cells ( Human Cheek Cell Wet
Mount)
1. Place a drop of water on a clean slide.
Gently scrape the inside of your cheek with the blunt end of a clean toothpick
and stir the material on the toothpick in the drop of water on the slide.
(properly dispose the toothpick)
2. Add one small drop of methylene blue stain to
the slide and then add a coverslip as directed.
3. Focus and examine the slide under low power
before moving to the higher magnifications.
4. Prepare a diagram showing 3 - 4 cells of the
cheek and label structures you can identify. (Don't forget to identify
magnification of the drawing.)
Answer the following questions.
4. What are the shapes of the cells?
_________________________________________
5. What cell structures can you
identify?______________________________________
6. Would the cells normally be attached to one
another? Explain. ____________________
7. Some of the cells may be folded or
wrinkled. What does this indicate to you about the thickness of the cells?
___________________________________________________
8. Explain how these cells differ from the plant
cells viewed previously._______________
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