Cheek, Onion, and Elodea lab - Stumptown Academy

Name:________________________________________________________ Period:__________ Investigating Eukaryotic Cells

Pre-Lab Assignment: Answer the following questions using complete sentences before beginning the lab.

1. What is the function of a chloroplast?

2. Predict how the amount of chloroplasts in a leaf cell would compare to those in a root cell.

3. What structures are found only in plant cells?

4. What structures are found in all eukaryotic cells?

5. What is the purpose of a cell wall? Why do animal cells lack a cell wall?

Teacher Initials ______ ____________________________________________________________________________________________ Introduction: Today you will be viewing three types of Eukaryotic cells: Plant Cell (Elodea and Onion) and an Animal

Cell (Cheek Cell). You will need to use your microscope skills to focus in on each cell and draw conclusions from what you observe.

Part I: Plant Cell - Elodea

1. Gather one elodea leaf from the teacher and make a wet mount slide of the elodea. Place the slide under the microscope and focus it. Start with the low power objective and work your way until you have focused the leaf using the high power objective.

2. In the box below a. Draw and color at least 3 cells of the Elodea leaf, b. Label the cell wall and a chloroplast in your drawing. You may be able to see a nucleus. It would be larger that the chloroplast but colorless or perhaps a darker circular region. c. Write the total magnification in the lower right hand corner of the drawing.

_____X

Name:________________________________________________________ Period:__________ Part II: Animal Cell - Cheek

3. Prepare a stained slide of your cheek cells using the following procedure: a. Put a drop of methylene blue on a slide. Caution: methylene blue will stain clothes and skin. b. Gently scrape the inside of your cheek with the flat side of a toothpick. Scrape lightly. c. Stir the end of the toothpick in the stain and throw the toothpick away. d. Place a coverslip onto the slide e. Use the SCANNING objective to focus. You probably will not see the cells at this power. 6. Switch to low power. Cells should be visible, but they will be small and look like nearly clear purplish blobs. If you are looking at something very dark purple, it is probably not a cell. Once you think you have located a cell, switch to high power and refocus.

4. In the box below, a. Draw and color a few of your cheek cells, b. Label the nucleus and cell membrane and any other organelles you can see, c. Write the total magnification in the lower right lower right hand corner of the drawing.

_____X

Part III: Plant Cell ? Purple Onion

5. Prepare an onion slide by taking a small piece of onion and making a wet mount. Place this slide on the stage and under the stage clips. Start with the low power objective and work your way until you have focused the Onion cell using the medium power objective. If you can, try to focus it on the high power objective.

6. In the box below, a. Draw and color two or more onion cells, b. Label the cell wall and any other organelles you can see. c. Write the total magnification in the lower right lower right hand corner of the drawing.

_____X

When finished, clean up your station. Return the microscope to the lowest stage position with the low power objective in place. Make sure your station is set up for the next group and all trash is thrown away.

Teacher Initials ______

Name:________________________________________________________ Period:__________

Analyze and Conclude 1. What two differences did you see between the plant cell (Elodea) and animal cell (Cheek)? 2. The animal cell did not have chloroplast. What can you infer about the animal cell? How does it get energy?

3. The onion cell did not have chloroplasts. What can you infer about that part of the onion plant?

4. Why are chloroplasts so important to support human life?

5. Use what you have learned in this lab and in previous activities to complete the table

Part A: Mark each column below with a check mark for the cell or cells the words or phrases describe. More

than one choice may be used for some words and phrases.

Description

Onion

Elodea

Fish

Rectangular

Chloroplast

Nucleus

Round or circular

Cell wall

Cytoplasm

No cell wall

Animal cell

Plant cell

Cell membrane

Part B: Can you relate the parts of the cell to your school? Match each cell function wit the corresponding school area.

_____Cell Wall

a. Supply or storage room

_____Vacuole

b. Doors or windows

_____Chloroplast

c. Principal's office

_____Nucleus

d. Bricks of the building

_____Cell Membrane

e. Cafeteria

 ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download