Download LAB-Plastids - hrsbstaff.ednet.ns.ca

Biology 11: Lab #1
Plastids
Some terms to know:
Plastid – membrane-bound cell organelle, mostly pigmented but may be
colorless.
Leucoplast – a colorless plastid that is involved in the metabolism and storage
of starches.
Anthocyanin – a red, purple or reddish-blue water-soluble pigment found in the
cell vacuole.
Chromoplasts – plastids responsible for pigment synthesis and storage.
Materials:
Tomato
Potato
Celery
Toothpick
Slide & cover slip
Procedure:
Tomato:
1. Using a toothpick, scrape a few cells off the “meaty” part of the tomato and
smear it on to the slide and a small portion of the skin and smear it on the
slide beside the “meaty” part. Add 1 drop of water then place the cover slip
over the top.
2. Using the high power objective, make a detailed drawing of the cells in the
field of view.
3. Label the cell wall, cell membrane, nucleus, cytoplasm, chromoplast and any
other part of the cell that is visible.
Potato:
1. Using a toothpick, scrape a few cells off the potato and smear it on the slide,
Add 1 drop of water then place the cover slip over the top.
2. Using the high power objective, make a detailed drawing of the cells in the
field of view.
3. Add 1 drop of iodine to the edge of the cover slip and draw the dye through
by placing a piece of tissue on the other side of the cover slip. Iodine turns
blue-black in the presence of starch.
4. Label the cell wall, cell membrane, nucleus, cytoplasm, leucoplast and any
other part of the cell that is visible.
Celery:
1. Using a toothpick, scrape a few cells off the celery and smear it on the slide,
Add 1 drop of water then place the cover slip over the top.
2. Using the high power objective, make a detailed drawing of the cells in the
field of view.
3. Label the cell wall, cell membrane, nucleus, cytoplasm, chloroplast and any
other part of the cell that is visible.
Questions:
Conclusion:
1. What is the colour of the tomato cell? What is responsible for the tomato’s
colour?
2. What is the shape of the tomato cell?
3. Compare the cell wall of the “meaty” part with the cell wall of the tomato skin.
Why is there a difference in their structure?
4. How are the chromoplasts arranged in the cell? Are they moving?
5. What is the colour of the potato cell? What is responsible for the potato’s
colour?
6. Did you see chromoplasts or chloroplasts in the potato cells? Why or why not?
7. Is there starch in the potato cells? If so, where is it located?
8. What is the colour of the celery cell? What is responsible for the celery’s
colour?
9. How are the chloroplasts arranged in the cell? Are they moving?
What is the function of the chromoplast, leucoplast and chloroplast? What
differences did you see that would distinguish each plastid from another?