Download Cells Lab - District 279

Name: ____________________________ Hr: _____
CELLS & CELL ORGANELLES LAB
Purpose: In this lab, you will learn to identify different cell types and certain organelles.
NOTE: When drawing cells seen
Objectives: Students should be able to:
though the microscope, draw only a
1. Recognize the major visible organelles of the cell.
few, large cells accurately. All
2. Give the function of the major organelles.
drawings must be labeled.
3. Draw animal and plant cells.
4. Tell the difference between animal and plant cells.
5. Demonstrate good lab technique and explain the techniques used.
PART A: Onion Skin.
1. Using the procedure used in the microscope lab to prepare a microscope slide of an
onion skin. (Thin skin layer only!)
2. Do not forget to add one drop of Iodine to your slide before adding the cover slip.
3. Draw and Label what you see, include these parts: cell wall, nucleus, and cytoplasm
Question #1: Why do we put stain on the onion?
Onion
PART B: Potato.
1. Cut an extremely thin piece of potato and place it on your slide.
2. Add 1 drop of Iodine to the slide and then cover slip the slide.
3. Examine the slide under low power and then high power.
4. Draw and Label what you see, include these parts: cell wall, cytoplasm, plastid
Potatoes are an underground stem. Next years new potatoes will grow from these stems.
The new potatoes will need a source of energy to live off of until they can grow leaves.
This energy comes from starch stored in the potato’s plastid. You can see how much
starch there is because starch will turn the plastid dark purple when Iodine solution is added to it.
Potato
Question #2: What is the organelle that is responsible for changing the glucose from photosynthesis into the
long term storage molecule starch?
Describe the shape of the potato cells:
QUESTION #3: Are these cells thin or thick? ______________________ Explain how you can tell.
Tomato
PART C: Tomato Skin.
1.
2.
3.
4.
Cut a small piece of skin from a tomato.
Scrape all of the “meat” off and place the skin on a slide skin side up.
Add 1 drop of water and cover slip. Do not add stain.
Draw and Label what you see, include these parts: cell wall, and plastid.
Name: ____________________________ Hr: _____
NOTE: There is color in these slides, even though there is no stain added. This color is called a “pigment.”
QUESTION #4: What organelle is responsible for making and storing this pigment?
QUESTION #5: What is the major function of the cells in the tomato skin?
Describe the shape of the tomato cells:
Cheek
Part D: Cheek Cells.
1. Using a clean toothpick, gently scrap the inside of your mouth as demonstrated by
your teacher.
2. Place these cells on a clean slide and a add 1 drop of methyl blue stain.
3. Put a cover slip on and examine the slide under low power, then under high power.
4. Draw and Label what you see, include these parts:
cell membrane, cytoplasm, and nucleus.
Question #6: Are these slides animal or plant?
Describe the shape and thickness of the cheek cells:
Question #7: What is the relationship between the cell’s shape and its function?
Part E: Elodea Leaf.
1.
2.
3.
4.
Place a young leaf from an elodea plant on a slide upside down.
Add a drop of water and then cover with a cover slip.
Examine the slide under low power, then under high power.
Draw and Label what you see, include these parts:
cell wall, cytoplasm, chloroplast, and nucleus.
5. Using low power, slowly turn the fine adjustment back and forth so you can observe
the various layers of the leaf.
6. Count and record the number of cell layers in the leaf. __________
Elodea
Question #8: Is there any evidence that this cell is living? _________________ If so, What?
Question #9: What organelle is the green color located in?
What chemical is responsible for the green color?