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Which Cell Parts Can You See With the Microscope?

Which Cell Parts Can You See With the Microscope?

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Name: _________________________________________________ Date: ________________ Period: ____<br />

<strong>Which</strong> <strong>Cell</strong> <strong>Parts</strong> <strong>Can</strong> <strong>You</strong> <strong>See</strong> <strong>With</strong> <strong>the</strong> <strong>Microscope</strong>?<br />

Introduction: Living things are made of cells. All cells have parts that do certain jobs. <strong>Cell</strong>s have an outer covering called <strong>the</strong> cell (plasma)<br />

membrane. The cell membrane controls what can enter/exit a cell. The clear jellylike material inside <strong>the</strong> cell is <strong>the</strong> cytoplasm. The nucleus is <strong>the</strong><br />

control center of <strong>the</strong> cell. Plant cells have a thick outer covering called <strong>the</strong> cell wall. It is found on <strong>the</strong> outside of <strong>the</strong> cell membrane.<br />

<strong>Cell</strong> parts can be studied by making wet mounts slides. A wet mount slide is a temporary slide. It is not made to last a long time. <strong>You</strong> can make<br />

wet mount slides of living and once living materials to study cell parts.<br />

Materials:<br />

• Glass slides<br />

• Droppers<br />

• Onion skin<br />

1. Place <strong>the</strong> specimen in<br />

<strong>the</strong> center of a CLEAN<br />

slide.<br />

1. Place a drop of stain at one end of <strong>the</strong><br />

cover slip.<br />

• Cover slips<br />

• Forceps<br />

• Various prepared slides<br />

Procedures: Making a Wet Mount Using Water<br />

2. Place a drop of water<br />

on <strong>the</strong> specimen.<br />

3. Place a cover slip on <strong>the</strong><br />

slide. Put one edge of <strong>the</strong><br />

cover slip into <strong>the</strong> drop of<br />

water, and slowly dower<br />

<strong>the</strong> cover slip over <strong>the</strong><br />

specimen.<br />

Procedures: Staining a Specimen<br />

Identify <strong>Microscope</strong> <strong>Parts</strong>: Read page R8 of your textbook and label <strong>the</strong> microscope picture below.<br />

1. <strong>Which</strong> two parts do you think should be held when carrying a microscope?<br />

___________________________<br />

2. <strong>Which</strong> microscope part:<br />

a. Adjusts <strong>the</strong> amount of light that enters <strong>the</strong> microscope?<br />

_____________________<br />

b. Focuses <strong>the</strong> image under high power?<br />

_____________________<br />

c. Holds and turns <strong>the</strong> objective lenses?<br />

_____________________<br />

• <strong>Microscope</strong>s<br />

• Elodea leaf<br />

• 50 ml beaker<br />

4. Remove any air<br />

bubbles from under<br />

<strong>the</strong> cover slip by gently<br />

tapping <strong>the</strong> cover slip<br />

Filter paper<br />

5. Dry any excess<br />

water before placing<br />

<strong>the</strong> slide on <strong>the</strong><br />

microscope stage for<br />

viewing.<br />

2. Hold a piece of filter paper with forceps at <strong>the</strong><br />

o<strong>the</strong>r end of <strong>the</strong> cover slip. The stain will flow<br />

underneath <strong>the</strong> cover slip and stain <strong>the</strong> specimen.


Specimen #1: Prepare a wet mount of onion cells.<br />

1. Obtain a clean slide and place a drop of iodine in <strong>the</strong> middle of <strong>the</strong> slide. If needed, rinse your slide with water and wipe dry<br />

to clean.<br />

2. Peel a thin layer of cells from <strong>the</strong> inside of an onion as seen in <strong>the</strong><br />

picture to <strong>the</strong> right. If <strong>the</strong> onion layer is not thin, peel ano<strong>the</strong>r layer.<br />

3. Place <strong>the</strong> onion peel in <strong>the</strong> drop of iodine.<br />

4. Add a cover slip over your onion.<br />

5. Examine <strong>the</strong> onion under medium and high power and using a pencil,<br />

draw your observations below.<br />

6. Be sure to find and label <strong>the</strong> <strong>Cell</strong> wall, Nucleus, Cytoplasm, and Nucleolus (optional).<br />

Onion Analysis: Best Writing Skills (complete sentences)<br />

1. Onion cells (and skin cells) are flat and seem to overlap. Explain why this arrangement is beneficial.<br />

____________________________________________________________<br />

____________________________________________________________<br />

Specimen #2: Prepare a wet mount of Elodea cells.<br />

1. Obtain a clean slide and place a drop of water in <strong>the</strong> middle of <strong>the</strong> slide. If needed, rinse your slide with water and wipe dry to<br />

clean<br />

2. Pick a leaf from <strong>the</strong> Elodea plant and place <strong>the</strong> leaf in <strong>the</strong> drop of water. Make sure <strong>the</strong> leaf is flat.<br />

3. Add a cover slip over your elodea cell.<br />

4. Examine <strong>the</strong> elodea under medium and high power and using a pencil, draw your observations below.<br />

5. Be sure to find and label <strong>the</strong> <strong>Cell</strong> wall, Chloroplast, and <strong>the</strong> Cytoplasm.


Elodea Analysis: Best Writing Skills (complete sentences)<br />

1. In what particular process do <strong>the</strong> chloroplasts function?<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

2. Using <strong>the</strong> fine adjustment with high power, focus up and down on one particular cell. As you focus, some of <strong>the</strong> chloroplasts go<br />

out of view and o<strong>the</strong>rs come into view. How can you explain this?<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

3. Why do you think it is important to have plants like Elodea in a balanced aquarium?<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

Specimen #3: Prepare a wet mount of your cheek cells.<br />

1) Obtain a clean slide and add a drop of methylene blue in <strong>the</strong> middle of <strong>the</strong> slide. If needed, rinse your slide with water and wipe dry to<br />

clean.<br />

2) GENTLY rub <strong>the</strong> flat end of <strong>the</strong> toothpick against <strong>the</strong> inside of your cheek.<br />

3) Rub <strong>the</strong> used toothpick in <strong>the</strong> drop of methylene blue to transfer your cheek cells.<br />

4) Add a coverslip and observe under medium and high power of your microscope.<br />

5) Draw a picture of your cheek cells and label <strong>the</strong> parts you can see.<br />

Cheek Analysis: Best Writing Skills (complete sentences)<br />

1. Review your drawing of an elodea cell. What differences do you notice between an animal cell and a plant cell that can carry on<br />

photosyn<strong>the</strong>sis?<br />

____________________________________________________________<br />

____________________________________________________________<br />

____________________________________________________________<br />

Specimens 4 and 5: Examine prepared slides of cork and blood.<br />

1. Obtain a prepared slide of cork and blood from your teacher.<br />

2. Place <strong>the</strong> slides under <strong>the</strong> microscope and observe. Draw <strong>the</strong> power that best shows <strong>the</strong> cells.<br />

3. Draw and label <strong>the</strong> parts you can see on <strong>the</strong> next page.


Cork Analysis: Best Writing Skills (complete sentences)<br />

1. Knowing that cork is <strong>the</strong> remains of dead plant cells, which part (or parts) were you able to see? What is <strong>the</strong> function of this<br />

(<strong>the</strong>se) part(s)?<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

Blood Analysis: Best Writing Skills (complete sentences)<br />

1. What is <strong>the</strong> function of red blood cells? How does <strong>the</strong>ir shape allow <strong>the</strong>m to do <strong>the</strong>ir job?<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

General Analysis: Best Writing Skills (complete sentences)<br />

1. When first viewing an object under <strong>the</strong> microscope, explain why you should always find it under <strong>the</strong> lowest power available.<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

2. Why do cells have different shapes?<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________<br />

_____________________________________________________________________

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