Download Procedure Part 4: Examining Animal Cells

Lab: Cell Survey
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Lesson Title: Cell Survey Lab
Grade/Age Level: Middle school grades 6-8 (age 11-14)
Subject Area: Life Science
Number of Classes for Lesson Completion: (3) 45-Minute Class Sessions
Lesson Description
Students will use a compound microscope to examine a variety of cells from the plant, animal,
fungi, and bacteria kingdoms
Pennsylvania Standards for Science and Technology
The following Pennsylvania Standards will be addressed during the lesson
3.1.6.A4
Recognize that all organisms are composed of cells and that many organisms are
unicellular and must carry out all life functions in one cell
3.1.6.A6
Identify examples of unicellular and multi-cellular organisms
3.1.7.A5
Explain how the cell is the basic structural and functional unit of living things
3.1.7.A6
Identify the levels of organization from cell to organism
Instructional Objectives
o To view differences between prokaryotic and eukaryotic cells
o To gain experience using the microscope
o To view cells from the following kingdoms: Plant, Animal, Bacteria, Fungi
Lab: Cell Survey
Instructional Procedures
o Lesson Set
1. Use the diagram on
http://edtech2.boisestate.edu/pattymcginnis/506/Cell_Site/506_cellular_organization.
html to demonstrate cellular organization. Explain that they will be looking at
different types of cells.
2. Introduce students to the different types of cells by having them access
http://edtech2.boisestate.edu/pattymcginnis/506/Cell_Site/506_types_of_cells.html.
Ask students to use their textbook to identify several major cell parts.
3. Ask students to answer the following questions. Discuss answers and demonstrate
images of cells using interactive white board.

What does the cell theory say?

Why do you think we should study cells?

Define:

Prokaryotic Cells

Eukaryotic Cells

Give an example of a prokaryotic cell.

Give two examples of eukaryotic cells.
o Techniques and Activities
Students will use compound microscope to view a variety of cells; refer to lab sheet
following this lesson plan
o Lesson Closure
Ask students to use what they have learned to compare cells in different kingdoms
Adaptations for Learners with Special Needs
Have images of the required cells posted into a power point presentation which can be shown on
an interactive white board. Allow students to go up to the board to confirm their findings. This
accommodation will benefit both learners who have visual impairment and learners who are
having difficulty identifying organelles within the cells
Extension and Remediation Activities
o Extension
Have a variety of prepared slides available for students who finish early or would like
additional practice with the microscope
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Lab: Cell Survey
o Remediation
Reduce the number of required images to accommodate slower students. Partner with a
capable student or enlist “student helpers” to check to see if specimens are focused
properly
Assessment
o Lab activity will be collected and assessed for quality and accuracy of work (detailed and
labeled drawings)
o Lab quiz will be administered in which students will be expected to recognize, describe,
and label cells similar to the ones observed in lab
Learner Products
Learners will complete the following lab activity and submit their drawings for assessment
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Lab: Cell Survey
STUDENT HANDOUT
Lab: Cell Survey
OBJECTIVES
 To see the differences between prokaryotic and eukaryotic cells.
 To gain more experience using the microscope.
 To view cells from the following kingdoms: Plant, Animal, Bacteria, Fungi
Pre Lab Questions:
1. What does the cell theory say?
2. Why do you think we should study cells?
3. Define:
a. Prokaryotic Cells
b. Eukaryotic Cells
4. Give an example of a prokaryotic cell.
5. Give two examples of eukaryotic cells.
PROCEDURE
Part A: Observing Bacterial Cells
Bacterial cells can be round, spiral shaped, or rod shaped. Draw simple sketches of the bacteria
focusing on shape of the cells. Make the sketches in the spaces below. For each, note whether
the bacterium is round, rod-shaped, or spiral-shaped. Don’t forget to write in the magnification.
1.
Make a wet mount from the dilute yogurt by adding one drop to a slide.
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Lab: Cell Survey
2. Make a wet mount of the pickle juice by adding one drop to a slide.
Yogurt
Magnification _____
Shape: ______________
Pickle Juice
Magnification _____
Shape: _____________
Part B: Observing Fungi Cells
Prelab Questions:
1. What is a spore?
2. What is the purpose of a spore?
Procedure Part B:
1. Make a wet mount of the yeast solution by adding one drop to a slide. Add a drop of
stain and then cover with a cover slip. Draw in the space below.
2. Take a piece of mushroom gill and tap it onto the slide. Add a drop of water to make a
wet mount. Draw it in the space below. Look for the black circles; they are spores.
Yeast
_____Magnification
Mushroom
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_____ Magnification
Lab: Cell Survey
Part C: Observing Plant Cells
Background: In addition to chloroplasts, some plants have leucoplasts for storing starch (like
potatoes) or chromoplasts for additional colors. Note: things that have starch in them turn
BLACK when iodine is added.
Pre Lab Questions
1. What is a chloroplast?
2. What is the job of a chloroplast?
3. What color are chloroplasts?
4. What is a cell wall?
5. What is the job of the cell wall?
Procedure Part C:
Elodea Leaf
1. Prepare a wet-mount slide of an Elodea leaf. Find the cell wall, cytoplasm, nucleus, and
chloroplasts.
2. Draw and label one cell from the Elodea. Label the cell wall, cytoplasm, nucleus, and
chloroplasts.
3. Sketch a representative Elodea cell as observed under high power, and label its parts.
Specimen: Elodea
Magnification: ______________________
Shape and Description: ________________
_______________________________
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Lab: Cell Survey
4. Do the chloroplasts appear to move?
Describe their movement.
Onion Cells
5. Prepare a wet-mount slide of onion tissue OR use a prepared slide. Onions (Allium) have
layers of modified leaves (scales) that can easily be separated from one another. Peel off a
portion of one layer and examine the concave side of the piece you have obtained (the side
that curves inward). The surface is covered by a thin layer of cells, the epidermis.
6. Remove a small piece of the epidermis by breaking the scale (modified leaf) gently. Peel the
epidermis from one of the halves of the scale. Prepare a wet-mount slide of the isolated
epidermis.
7. Observe the onion cells using low power (10X objective) and then high power (40X
objective).
8. If it is difficult to see the cells, add a drop of iodine.
9. Sketch one of the onion cells under high power, and label the cell wall, nucleus, and
cytoplasm.
Specimen: Onion Cell
Magnification: ______________________
Shape and Description: ________________
_______________________________
8. Compare the onion cell with the Elodea cell. Since they are both plant cells, they should be
similar. You will note that onion cells lack one structure (organelle) that is very conspicuous in
Elodea cells.
9. What is this organelle missing in the onion cells?
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Lab: Cell Survey
10. List the similarities and differences between Elodea cells and onion cells.
Similarities
Differences
Potato Cells
1. Prepare a wet mount slide of a potato. Do this by using a plastic knife to scrape some
cells onto a microscope slide. Do not cut the potato!
2. Prepare a wet-mount slide by adding a drop of water and a drop of iodine to your slide.
3. Study the slide at low power (10X objective) and then at high power (40X objective).
Specimen: Potato Cells
Magnification: ______________________
Shape and Description: ________________
_______________________________
_______________________________
4. Do you see any chloroplasts?
Why or why not?
5. You will probably see some small oval-shaped blue-black structures. These
leucoplasts store starch. Why did they turn blue?
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Lab: Cell Survey
Banana Cells
1. If a banana is available, scrape a small amount of tissue from its surface and spread it
onto a slide. Add a drop of iodine and a cover slip. Observe the preparation using high
power (40X objective).
2. How do these observations compare with what you saw in the potato?
Specimen: Banana Cells
Magnification: ______________________
Shape and Description: ________________
_______________________________
_______________________________
Carrot Cells
1. Prepare a wet mount slide of carrot or red pepper. Use a plastic knife to scrape some cells
onto a slide. Prepare a wet-mount slide using a drop of water.
2. Can you see the chromoplasts? Sketch them.
Specimen: Carrot Cells
Magnification: ______________________
Shape and Description: ________________
_______________________________
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Lab: Cell Survey
Procedure Part 4: Examining Animal Cells
Animal cells can be studied using the light microscope, but most of the cellular organelles within
the cytoplasm are not visible without the use of special staining techniques. You can usually fine
the nucleus, the cell membrane, and the cytoplasm.
To study the structure of animal cells you will use prepared slides of animal tissues. These are
collections of cells that have a similar function. The cells are usually organized into sheets.
1.
Obtain a prepared slide of cheek cells. Sketch a few cells, and label the plasma membrane,
nucleus, and cytoplasm.
Specimen: Cheek Cells
Magnification: ______________________
Shape and Description: ________________
_______________________________
_______________________________
2. Do the cheek cells have a cell wall?
3. Do they have chloroplasts_________
4. List the similarities and differences between the plant cells and the animal cells you have
observed.
Similarities
Differences
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Lab: Cell Survey
REVIEW: For the lab quiz, be able to recognize, describe, and label the different types of cells
we have examined today. You should be able to discuss the similarities and differences
between the different cell types.
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