Download Plant cell Lab Instructions

http://www.biologycorner.com/lesson-plans/cells/
SJB 10/2011 revised 5/5/2017
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Name: ____________________________________Lab Partner: _______________________________
Per. ________ Date: _______________
Learning Target: Plant Cell Lab
I Can… Observe, identify, compare and contrast cellular organelles of various plant eukaryotic cells
under the compound light microscope.
I Will…
 Illustrate structure of the cells and identify the visible organelles in the following cells; Elodea,
onion, potato, tomato, and lettuce.
Materials: Compound light microscope Microscope slide
Iodine stain
Methylene blue stain
Cover slip
Water with dropper
Toothpicks
NOTE: BE CAREFUL – IODINE AND METHYLENE BLUE WILL STAIN CLOTHES
PERMENANTLY!
Procedure:
Plant Cells: Onion
1. Obtain a small piece of onion.
Remove skin if present.
2. Use forceps/tweezers to remove a thin layer of epidermal
cells by gently pulling it away from the inner surface of the
onion piece.
3. Place the layer of epidermal cells on a microscope slide (Be
careful not to wrinkle or fold up epidermal layer).
4. Place a small drop of iodine on top of the cell layer on the
slide.
5. Cover with coverslip by placing the coverslip at a 45 degree
angle and dropping onto cells with iodine careful not to create
air bubbles.
6. Focus with scanning objective. (4x red)
7. Switch to Low Power Objective and view cells. (10x
yellow)
8. Switch to High Power Objective and view cells (40x blue)
9. Sketch and label onion cells. Cell wall, Cell membrane, Cytoplasm, Nucleus, and Nucleolus
10. Complete Lab Analysis questions for the onion cells.
Now you are a pro at making wet mount slides; follow similar techniques and provided
instructions for the following cells.
http://www.biologycorner.com/lesson-plans/cells/
SJB 10/2011 revised 5/5/2017
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Plant Cells: Elodea
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Obtain ONE leaf from the aquatic Elodea plant.
Prepare a wet mount using water only (no stain is needed since it is already green).
Focus with scanning objective (4x red).
Switch to Low Power (10x yellow), resolve focus.
Switch to High Power (40x blue), resolve focus.
Note the small green circular organelles inside the cells. These are chloroplasts. By shining the light
on them, they will begin to move around inside the cell. This movement is called “cytoplasmic
streaming”.
7. Sketch and label ONE CELL on High Power.
8. Label the following organelles: Cell wall, cell membrane, cytoplasm, chloroplasts
a. The nuclei of the plant cells here are difficult to see because the chloroplasts take up so
much space in the cell.
9. Complete Lab Analysis questions for the Elodea cell.
Plant Cells: Potato Cells
1. Prepare a wet mount; place a thin slice of potato on the slide and add a drop of IODINE then cover
with coverslip.
2. Focus with scanning objective (4x red).
3. Switch to Low Power (10x yellow), resolve focus.
4. Switch to High Power (40x blue), resolve focus.
5. Sketch ONE CELL on the High Power.
6. Note the dark purple or black circles; these are Amyloplasts.
7. Label the following organelles: Cell wall, cell membrane, cytoplasm, amyloplast
8. Complete Lab Analysis questions for the Potato cells.
Plant Cells: Tomato Cells
1. Prepare a wet mount; place a thin slice of tomato skin on a microscope slide, add a drop of water (no
need to add any stain) and cover with coverslip.
2. Focus with scanning objective (4x red).
3. Switch to Low Power (10x yellow), resolve focus.
4. Switch to High Power (40x blue), resolve focus.
5. Sketch ONE CELL on the High Power.
6. Note; plastids are organelles that give the tomato its color. A chloroplast is a plastid that contains
chlorophyll to give cells green color. Not all plastids contain chlorophyll so not all are green. The
plastids in tomatoes produce lycopene and carotene when mature, and the temperature is between
50°F and 85°F. This process is triggered by ethylene production that is produced when the tomato
matures
7. Label the following organelles: Cell wall, cell membrane, cytoplasm, plastids.
8. Complete Lab Analysis questions for the Tomato cells.
http://www.biologycorner.com/lesson-plans/cells/
SJB 10/2011 revised 5/5/2017
Plant Cells: Lettuce Cells
1. Prepare a wet mount; place a drop of water (no need to add any stain) on a
microscope slide.
2. Take a small piece of a lettuce leaf and bend it until it “snaps”. Slowly one side
under the other so that a clear, thin portion, or membrane, of the epidermis is
peeled off and hanging from the sides.
3. Use forceps to place the thin portion of the epidermis onto the drop of water on
the slide (make sure the membrane doesn’t fold over).
4. Cover with coverslip.
5. Focus with scanning objective (4x red).
6. Switch to Low Power (10x yellow), resolve focus.
7. Switch to High Power (40x blue), resolve focus.
Guard
8. Sketch a group of cells on the High Power.
cells
9. Label Cell Wall, Cell membrane, Cytoplasm, Stomata, and
Guard cells
a. Stomata are openings that allow gas exchange surounded by two guard cells.
Stomata
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