Tuesday, May 10, 2016

GRAM STAINING

 Introduction:
Gram staining is a method of differentiating bacterial species into two large groups: Gram positive and Gram negative.

Objectives:
1. Differentiate yogurt bacteria (Streptococcus and Lactobacillus)
2. Relate the staining procedure with the structure of the cells.

Material:
- Slide
- Cover slip
- Tongs
- Needle
- Gram stain: crystal violet, iodine and safranin
- Decolorize reagenti: ethanol 96%
- Microscope
- Yogurt

Procedure:
1. Fix the piece go yogurt
2. Add crystal violet (1 minute and 30 seconds)
3. Add water
4. Add Lugol (1 minute)
5. Add water
6. Add ethanol
7. Add safranin (1 minute)
8. Add water




Observations:
We can see the bacteria of the yogurt 

Tuesday, May 3, 2016

MITOSIS IN AN ONION ROOT

Introduction: 
In this experiment we will see the parts of the mitosi (interfase, profase, metafase, anafase and teloface) in a onion root.



















Material:
- Microscope
- Slide
- Coverslip
-Dropper
-Needles emmanegades
- Watch glass
- Beaker
- Thin tongs
- lighter
- Cellulose paper

Quemical products: distilled water, Orceine A and B and normal water.
Natural products: Onion

Procedure: 

1). Put the onion in a beaker with water one week (the roots need to touch the water). 
2). When the roots grow up 3cm, cut the final 4 mm and put in the watch glass with orceine A. 
Then, you need to put in  the heater with the flame of the lighter until you see vapor (In this process the temperature can't pass the 60 C). 
3). With the tongs take the piece of the root and put in a slide and put the orceine B with the dropper. 
4). Put the coverslip and with a piece of cellulose paper you need to push and turn in the coverslide to extend de cells. 
5). Observe with the microscope with 600 increases and you will see the parts of the mitosi. 







Observations: 


In this experiment we can't see very well the different parts of the mitosis. 


Monday, April 25, 2016

NANOENCAPSULATION

Material: 
- Sodium alginate
- Sodium chloride
- Coca-Cola
- Beaker
- Pipet
- Strainer

Procedure: 
- We need to mix the sodium chloride with the sodium alginate (contain the coca-cola).
- You will see a gelatinous form that precipitated and you will have the pill.
- Take the strainer and the coca-cola is inside.

Process of nanoencapsulation:













APLICATIONS OF NANOENCAPSULATION:
1. The first aplication is with the food industry: incorporation food ingredients, enzymes, cells or other materials in small devices (nano- scale or micrometer). These devices are obtained
coating or Entrapment of a material or a mixture.




2. In the second aplication we see the development of new materials,  including biomaterials and biocomposites for food, pharmaceutical, biomedical, chemical and hydrocarbon packaging applications.

3. Development of new micro and nanoencapsulation systems for the protection of various bioactive ingredients

BIOTEST

Material:
- Nanoparticles of gold
- Watch glass
- Distilled water
- Water with sugar
- NaCl

Procedure: 
We need to know that the nanoparticles of gold change their color when we change the aggregation.
- Take the watch glasses with nanoparticles.
- In the first one put distilled water (don't change the color).
- In the second one put water with sugar (don't change the color).
- In the third one put NaCl (the color change).


Question: 
Why change the color when we put NaCl?
Because the nanoparticles of gold do the aggregation (recombination of the nanoparticles).

BIOTOXICITY

Material:
- Nanoparticles of silver
- Sugar and yeast
- Distilled water
- Erlenmeyer
- Hot plate
- Ballon
- Spatula
- Pipet

Procedure:
We need to know that the nanoparticles damage the live cells and toxit activity.
- Take three erlenmeyer:
                            1r: Control: One spoon of sugar, yeast and water.
                            2n: The same quantity of sugar, yeast, water and 1ml of nanoparticles of                                               silver.
                            3r: The same quantity of sugar, yeast, water and 3ml of nanoparticles.

- Put the Erlenmeyers in the hot plate.




Conclusions:
We see that the experiment produce CO2 and we see that the ballon inflate.

Question:
Why not inflate the last ballon?
Because the nanoparticles kill the yeast and there isn't fermentation.


NANOSCALE

Material: 
- Two beakers
- Mortes
- Two effervescent tablet

Procedure: 
1. We need to take the two effervescent tablet.
2. We need to brake one of the effervescent tablet using the morter.
3. In each beaker put a little bit of water.
4. In the first beaker put the effervescent tablet, and in the second beaker put the broken one.
















Conclusions: 
We can see that the broken effervescent tablet have a quickly reaccion than the other one.

Question: 
Why the crushed table was faster? 
Because there are more surface and the nanoparticles react more quickly.

Monday, March 14, 2016

LEAF PIGMENT CHROMATOGRAPHY

Introduction: In this experiment we will see different plants pigments. That pigments are: chlorophyll, xanthophyll and carotens.

Objective: 
To do the process of chromatography (separate the pigments with ethanol)

Material: 
- Mortar ans Pestle
- Funnel
- Scissors
- Graduated Cylinder
- Sand
- Beaker (250ml) or a petri dish
- Ethanol
- Calcium carbonate
- Spinachs
- Cellulose paper

PROCEDURE:
1. Take 6/7 leafs of spinacks and cut in small pieces with the scissors.
2. Put the small pieces inside the mortar with the spatula and put a little bit of sand inside de mortar.
3. With the spatula take calcium carbonate and put inside with the leafs and the sand.
4. Add 50 ml of ethanol.
5. You need to grind
6. Finally, you need to filter the mixture and extract the liquid.



- Cut a paper strip with the cellulose paper and put inside the beaker (with the liquid that we extract)
- Do the same with the petri dish, but you need to bend the cellulose paper.
- The liquid that you have in the graduated cylinder put in front of the light.


QUESTIONS: 
1. Why do we add sand?
To brake the cells, we brake the cloroplast.
2. Why do we add calcium carbonate?
Prevents the pigments degradation.
3. Which is the color of every pigment?
 chlorophyll (verd), xanthophyll (yellow) and carotens (orange).
4. What adaptative purpose do different colored pigments serve for a plant?
to capture different light wavelengths
5. Why do they separate on the cellulose paper?
For the solubility

CALCULATE: