ACTIVITAT ENZIMÀTICA DE LA CATALASA EN ELS DIFERENTS TEIXITS ANIMALS I VEGETALS.

1. INTRODUCCIÓ

Valorem de forma quantitativa l'activitat enzimàtica de la Catalasa del fetge del pollastre. Dividirem la pràctica en dues parts. En la primera observarem la diferència d'activitat de la catalasa en diferents teixits animals i vegetals. Per aquesta part utilitzarem la patata, el tomàquet i el fetge de pollastre. En la segona part veurem l'influència de determinants factors en l'activitat enzimàtica.

La catalasa és un enzim present en els peroxisomers de les cèl·lules animals i vegetals que s'encarrega d'eliminar l'aigua oxigenada que es forma en algunes reaccions del metabolisme. La reacció química és la següent:


                                          H2O2----------------------> 2H2O + O2

2. MATERIAL

- Fetge i cor
- Patata, tomàquet i pastanaga
- Tub d'assaig
- Termòmetre
- Pinces
- Bisturí
- Aigua oxigenada al 3%

3. PROTOCOL

1.- Experiment 1.

- Tallem 2 trossos de patata i el tomàquet que pesin més o menys el mateix (mateixa mida) (1cm3 aprox.)

- També tallarem un tros de fetge de la mateixa mida i pes.

- Ho posarem en tres tubs:

1er tub: patata + 5mL aigua destil·lada
2on tub: tomàquet + 5mL aigua destil·lada
3er tub: pastanaga + 5mL aigua destil·lada
4art tub: fetge + 5mL aigua destil·lada
5è tub: cor + 5 mL aigua destil·lada

- Posarem 2mL d'aigua oxigenada i marcarem l'alçada que assoleixen les bombolles en cada tub. Mesurarem aquesta alçada en mm.

4. PREGUNTES

- Variable dependent i independent?
Dependent: L'alçada de les bombolles
Independent: Diferents teixits
- Problema que vol investigar?
Quin teixits presenta més activitat de la catalasa?
- Explicació del resultasts:
Els texts animals presenten més activitat que els vegetals.

5. RESULTATS

Teixit	Alçada bombolles (mm)
Patata	45mm
Tomàquet	45mm
Pastanaga	47mm
Fetge	98mm
Cor	60mm

Experiment 2.

1er tub: Tros de teixit animal a temperatura ambient

2on tub: Tros de teixit animal amb 10 mL d'HCL al 10%

3er tub: Tros de teixit animal congelat

4at tub: Tros de teixit animal bullit

5è tub: Tros de teixit submergit en una dissolució saturada de NaCl

- Afegirem 2mL d'aigua oxigenada i anotarem l'alçada de les bombolles

1. RESULTATS

Tubs	Alçada de bombolles (mm)
Tub 1	60mm
Tub 2	41mm
Tub 3	58mm
Tub 4	44mm
Tub 5	42mm

L21: MITOSI

1. OBJECTIVES

- Find the phases of cell divisions onion.

2. MATERIAL

- Onion
- Orceine A and B
- Dropper
- Whatch glass
- Forceps
- Beaker
- Bunser burner
- Lighter
- Microscope

3. PROCEDUCE

1. A week ago we left an onion in a beaker with some water, (only the tip of the onion touched it) so its roots will grow so we can see the process of mitosis.
2. To start our experiment we took the onion and cut the tip of a root and put it in the watch glass.
3. Then with the dropper we took the orceine A and put some drops on the root and we took the watch glass with the wooden forceps and put it on the bunsen burner so the orceine and the root would heat. Some acid fumes began to evaporate. We had to be careful to not to burn the root so the watch glass could not be too hot, we should be able to touch it with our hand!!
4. After that we took the root with the forceps and put it on a slide and added a couple of drops of orceine B, we waited a couple of minutes.
5. Then with the scalpel we cut 3mm leaving the tip, and always knowing where the tip is. 
6. Finally we added a coverslip and used the squash method so we could observe the cells on the microscope.

L20: PHOTOSYNTHESIS

1. OBJECTIVES

- Relate the light intensy with the photosynthesis process.
- Measure the rate of photosynthesis.
- Identify the products of the process and the variables that can affect it.

2. MATERIAL

- Algae (Elodea)
- 600 mL beaker
- Test tube
- Tap water
- Funnel
- Light souce
- Metric ruler

3. PROCEDUCE

1. First we assigned the different distances to do the experiment and compare the results to each group.
2. We took the 600 ml beaker and placed 7 g of an algae under a clear funnel inside the beaker. The funnel was raised off the bottom on pieces of blue-tack to allow unhampered diffusion of CO2 to Elodea. 
3. We didn't have sodium bicarbonate so we filled the beaker with tap water, the algae and the funnel should be completely under the water.
4. Then we filled a test tube with tap water and placed the thumb over the end of the test tube. We turned the test tube upside down taking care that no air enters and no water comes out and we put this test tube over the end of the funnel (the skinny part)
5. We marked the level of the water on the surface of the test tube with a marker pen.
6. Each group placed the preapartion close to a light source, each group placed the preparation in a different distance 5, 10, 20 and 25 cm, and one with no light source.
7. We also measured the temperature.
8. Finally we left this preparation for and hour and a half. After this time we measured the difference of gas accumulation on the top of the test tube. 

4. QUESTIONS 

1. Identify the dependent and independent variable of this experiment?

The dependent variable is the gas accumulation and the independent is the distance of the light.

2. Using the data from your results prepare a graph and describe what happened to amount of gas in the test tube.

 Andrea's blog.

3. How much gas produced in the test tube after 1 hour? And 1 hour and half?

4. Write the photosynthesis equation. Explain each part of equation. Which substances are produced by photosynthesis? Wich gas is produced that we need in order to live? 

6 CO2 + 6 H2O--------> C6H12O6+ 6 O2

O2------------>CO2

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