L19: CELLS ORGANELLES

 

Tomato Chromoplasts: 4 x 10= 40X

  

Potato amyloplasts, stained with lugol: 10 x 40 = 400X

Potato amyloplasts, stained with lugol: 10 x 100 = 1000X

Chromoplasts red cabbage: 15 x 10 = 150X

Chromoplasts red cabbage; 15 x 40= 600X

Stoma of a red cabbage; 15 x 40= 600X

Carrot Chromoplasts : 100X

Chloroplasts of Vallisneria

L18: LIFE IN A DROP OF WATER

In this picture we can see flagel, that moves throught water.
The flagel moves very quickly. Thanks to its movement, causes current of water.

We can see the video: http://www.youtube.com/feature=player_embedded#t=30


In this pic

L17: GRAM STAINING

1. OBJECTIVES

- Differenciate yogurt bacteria.
- Relate the staining procedure with the structure of the cells.

2. MATERIAL:

- 1 Slide
- 1 Cover slip
- Tongs
- Needle
- Gram stain: crystal violet, iodine and safranin.
- Descolorize reagent: ethanol 96%
- Microscope
- Yogurt

3. PROCEDURE

- PROKARIOTIC CELL OBSERVATIONS: GRAM STAINING

1. Prepare a heat-fixed sample of the bacteria to be stained.
2. Cover the smear with crystal violet for an exposure of 1 min.
3. Rinse with distilled water.
4. Apply Iodine solution for 1 min.
5. Rinse the sample with distilled water.
6. Decolorize using ethanol. Drop by drop until the purple stops flowing. Wash immediately with distilled water.
7. Cover the sample with the safrain stain for an exposure time of 45 seconds.
8. Rinse the sample with distilled water.
9. Gently dry the slide with paper.

Gram-negative: stain pink of reddish color.
Gram-positive: stain purple color.

4. RESULTS AND OBSERVATIONS

L16: EPIDERMIS CELLS

1. OBJECTIVES

- Identify the shape of epidermis cells.
- Identify and explore the parts of stoma.
- Measure dimensions of the entire cell and stoma.

2. MATERIAL

- 1 Slide
- 1 Cover slip
- Distilled water
- 10% Salt water
- Scissors
- Needle

3. PROCEDURE

- PLANT CELLS OBSERVATION:

1. Cut the stalk of the leek.
2. In the place of the cut, pull out the transparent part of the epidermis using forceps.
3. Using the brush, place the peel onto the slide containing a drop of tap water.
4. Take a cover slip and place it gently on the peel with the aid of a needle.
5. View it in the microscope.
6. Describe the change in the shape of the cells.
7. Draw a diagram with the parts of a stome: stoma,cell guards,epidermis cells.

- SALT TREATMENT:

1. Prepare a 10% of salt solution.
2. Put the salt with a dropper on the left part of the slide.
3. Place a piece of cellulose paper in the opposite part of the cover slip, and let the dissolution to go though you sample.

4. RESULTS AND OBSERVATIONS

L15: ANIMAL CELLS vs PLANT CELLS

1. OBJECTIVES

- Identify the major components of cells.
- Differenciate between animal and plant cells,
- Measure dimensions of the entire cell and the nucleous.

2. MATERIALS

- Toothpick
- 2 Slides
- 2 Covers slips
- Distilled water
- Methylene blue
- Iodine
- Onion
- Glycerine
- Two whatch glasses
- Dropper
- Needle

3. PROCEDURE

- PLANT CELLS OBSERVATION:

1. Pour some distilled water into watch glass.
2. Peel off the leaf from half a piece of onion and using forceps, pull out a piece of transparent onion peel (epidermis) from the leaf.
3. Put the epidermis in the watch glass containing distilled water.
4. Take a few drops of iodine solution ( or safranin) in a dropper and transfer into another watch glass.
5. Using a brush ( or a needle), transfer the peel into the watch glass containing the dye, Let this remain in the safranin solution (or iodine) for 30 seconds, so that the peel is stained.
6. Take the peel from the iodine solution and place it in the watch glass containing distilled water.
7. Take a few drops of glycerine in a dropper and pour 2-3 drops at the center of a dry glass slide.
8. Using the brush, place the peel onto the slide containing glycerine.
9. Take a cover slip and place it gently on the peel with the aid of a needle.
10. Remove the extra glycerine using cellulose paper.
11. View it in microscope.

- CHEEK CELLS OBSERVATION:

1. Gently scrape the inner side of the cheek using a toothpick, wich will collect some cheek cells.
2. Place the cells on a glass slide that has water on it.
3. Mix the water and the cheek cells using a needle and spread them.
4. Dry the sample under the light to fix the sample on the slide,
5. Take a few drops of methylene blue solution using a dropper and add this to the mixture on the slide,
6. After 2-3 minutes remove any excess water and satin from the slide using cellulose paper.
7. Take a clean cover slip and lower it carefully on the mixture with the aid of a needle.
8. Using the top of the needle, press the cover slip gently to spread the epithetial cells,
9. Remove any extra liquid around the cover slip using cellulose paper.

4. RESULTS AND CONCLUSIONS

PLANT CELLS:

MRcell: 6,9/400= 0,017cm
0,17x10000= 172,5microns

MRnucleous; 400=0,7x10000/X
X=7000/400=17,5 microns


CHEEK CELLS:
400= 1,5x10000microns/X
X=1,5x10000microns/400=37,5

400=0,3x10000microns/X
X= 0,3x10000microns/400=7,5microns