LEAF PIGMENT CHROMATOGRAPHY

INTRODUCTION:

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

OBJECTIVES: 

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?

CHROMOPLAST & AMILOPLASTS OBSERVATION

INTRODUCTION: 

In this experiment observe the amyloplasts potato and tomato Chromoplast.

OBJECTIVES: 

- To see the pigments of the tomato and if all the cell is red. 

- With the potato, to see the aminoplasts

 PROCEDURE:

-Tomato

1. Peel the tomato and take a small part of the pulp. 

2. Prepare a procedure called squash. 

3. Observe with the microscope. 

4. Cut a small piece of paper (2cm) and you need to push and to turn with the finger to the tomato, and then take away the paper. 

OBSERVATIONS: 

The cells are transparent, and form red pigments that are the cloroplast. 

-Potato

1. You need to cut a small piece of potato and to take the white liquid that is insade of the potato with a dropper. 

2. You need to put the liquid with the light a few minutes (the liquid need to be dry). 

3. Put a few drops of lugol and wait 3 minutes. 

4. Observe with the microscope. 

Mirotome 

1. We need distilled water and with the microtome cut the piece of potato ant put inside the distilled water. 

2. Dye the piece of potato. 

3. Observe with the microscope.

 

OBSERVATIONS: 

You can see the aminoplasts. 

LIFE IN A DROP OF WATER

NTRODUCTION

In this experiment we took some drops of water of different places (water of a fishbowl, stagnant water... Etc)

OBJECTIVES:

- To see if there are organism alive.

MATERIAL:

- Dropper

- Microscope

- Coverslips

PROCEDURE:

1. We took with the dropper some drops of the different water.

2. We tried to see organisms alive with the microscope.

RESULTS:

16. RED ONION OSMOSIS

INTRODUCTION: 

In this experiment we will see the process called osmosis of a red onion, with different material (distilled water, salt water and a microscope).

OBJECTIVES:

- To see what happens to the piece of onion when we put distilled water and salt water.

PROCEDURE:

A) PHASE 1: NORMAL CELLS/DRY MOUNT 

1. Carefully slice away the colored layer of cells from the red onion. This should only be the thin purple layer. Trim to get a piece about this actual size.

2. Place the thin, purple onion layer on a dry microscope slide shinny side up-do not put on water or cover slip yet.

3. Scan the entire onion tissue on low power to find and center the most purple area and focus. Set the microscope to medium power and focus the view.

4. Take a picture

B) PHASE 2: SALT WATER ENVIRONMENT/WET MOUNT 

Now that you have observed the layer of normal cells which are the subject of this lab, make a wet mount using 2 or 3 drops of salt water solution on the onion tissue then install cover slip.

5. Watch the cells for approximately 2-3 minutes or longer as you again survey the entire onion tissue on low power. You should see changes within many of the cells intially near the perimeter of the onion tissue. As time passes all or most of the cells shoulb become affected by the salt water. Find some cells that have noticeably been affected and observe them under medium power.

Obervations: We can see the process of plasmolosis.

C) PHASE 3: DISTILLED WATER ENVIRONMENT/WET MOUNT 

6. After you have colored the diagram correctly above, you need to prepare for phase 3 of this lab by putting the entire salt water wet mount in the dish of tap water to rinse off the salt water from the slide, cover slip and onion tissue layer. Dry the slide and cover-slip then gently dab the onion tissue dry.

7. Make a wet mount of the onion tissue you just rinsed using 2 or 3 drops of distilled water on the onion tissue then install cover slip. Watch the cells for approximately 2-3 minutes or longer as you again survey the entire onion tissue on low power. You should see changes within many of the cells intially near the oerimeter of the onion tissue. As tine passes all or most of the cells should become affected by the distilled water. Find some cells that have noticeably been affected by the distilled water and observe them under medium power.

Observations: The cells become more bigger because they took the water

QUESTIONS:

1. When the salt solution was added to the onion cells, where was the greater concentration (most pure) of water? (inside or outside the cell membrane). How do know this? Explain:

Answer: Inside, because outside is the salt solution.

2. In the winter, grass often dies near the roads that have been covered in salt to remove the ice. Using what you have learned in this experiment, what do you think is the reason the grass dies?

Answer: The cells leaved water.

3. Which kinf of transport does water follow across the membrane?

Answer: Passive (membrane difussion)

15. ANIMALS CELLS vs PLANTS CELLS

INTRODUCTION:

In this experiment we will se the difference between animal cells and plant cells, using different food (onion).

OBJECTIVES:

1. Identify the major components of cells. 

2. Differemtiate between animal and plant cells. 

3. Measure dimensions of the entire cell and nucleus. 

PROCEDURE:

Plants cells observation

1.  Pour some distilled water into a watch glass. 

2. Peel off the leaf from half a piece of onion and using forceps, pull out a piece of transparent onion peel (epiderms) from the leaf. 

3. Put the epiderms 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 peel is stained. 

6. Take the peel from the iodine solution and place it in the watcg glass containing distilled water. 

7. Take a few drops of glycerine in a dropper and pour 2 or 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 in the microscope. 

RESULTS:

In this image we saw the nucleotids, stomas (to do the gases change: CO2 --> O2) and the cellular membrane.

12. DNA EXTRACTION

INTRODUCTION: 

Deoxyribonucleic acid (DNA) is a nucleic acid that encodes the genetic instructions used in the development and functioning of all known living organisms and many viruses.

Nucleic acids are biopolymers formed by simple units called nucleotides. Each nucleotide is composed of a nitrogen-containing nucleobase (G, T, C, A) as well as a monosaccharide and a phospate group.

OBJECTIVES: 
1. Study DNA structure.
2. Understand the process of extracting DNA from a tissue.

PROCEDURE:
- Prepare the buffer in a 0'5L beaker: Add 450mL of tap water, 25mL of a dish soap and 7g NaCl. Stir the mixture.

1- Peel the kiwi/banana and chop it to small pieces. Place the pieces of the kiwi in one 600mL beaker and smash with a fork until it becomes a juice puree. 

2- Add 8mL of buffer to the beaker. 

3- Mash the kiwi/banana puree carefully for 1 minute without creating many bubbles. 

4- Filter the mixture: put the funnel on top of the graduated cylinder. Place the cheesecloth on top of the funnel. 

5- Add beaker contain carefully on top of the cheesecloth to fill the graduated cylinder. The juice will drain through the chessecloth but the chucks of kiwi/banana will not pass through into the graduated cylinder. 

6- Add the pineapple juice to the green juice (you will need about 1mL of pineaplle juice to 5mL of the green mixture DNA solution). This step will help us to obtain a purer solution of DNA. Pineapple juice contains an enzyme that breaks down proteins. 

7- Tilt the graduated cylinder and pour in a equal amount of ethanol witg an automatic pipet. Put the ethanol through the sides of the graduated cylinder very carefully. You will need about equal volumes of DNA solution to ethanol. 

8- Place the graduated cylinder so that it is eye level. Using the stirring rod, collect DNA at the boundary of ethanol and kiwi/banana juice. Do not stir the kiwi juice; only stir in the above ethanol layer. 

9- The DNA precipitate looks like long, white and thin fibers. 

10- Gently remove the stirring rod and examine what DNA looks like.

RESULTS:

This is the final result when  took the DNA and we saw.

 

1.10 Protein desnaturalitation

Introduction

Desnaturalitation es a process in wich proteins or nucleicacids lose the quaternary, terciary and secondary structure that is present in their native State. Denaturatiom is the result of the application ofsome external stress (heat and pH change) or compounds such as a strong acid or base, a concentrated inorganic salt or organic solved.

Materials
-2x250mL beaker
-4 test tube
-Test tube rack
-10mL pipet
-Knife
-Glass marking pen
-Potato
-Distilled water
-Hydrogen perioxide
-NaCl
-HCl

Objectives

1-Study the relation between the structure and the function of proteins.                                                     
2-Understand how temperature, pH and salinity affect to the protein structure.

Catalasa activity

Caalasa is a common enzyme found in nearly all-living organisms exposed to oxygen. It catalyzes the decomposition of hidrogen perioxide (H2O2) to water an oxygen. It is a very important enzyme in protecting the cell from oxidative damage and preventing the accumulation of hidrogen perioxide.

2 H2O2 ----> 2H2O + O2

Procedure

In this experiment we are going to test the catalase activity in diferent environment situations. We  are going to measure the rate of enzyme activity under various conditions, such as different pH values and temperatures. We will measure catalase activity by observin the oxygen gas bubbles when H2O2 is destroyed. If lots of bubbles are producted, it means the reaction is happening quickly and the catalase enzyme is very active.

1-Prepare 30mL of H2O2 10% in a beaker (use a pipet).

2-Prepare 30mL of HCl 10% in a beaker.      à Solutions

3- Prepare 30mL of NaCl 50% in a beaker.

4-Peel a fresh potato tuber and cut the tissure in five cubesof 1cm3. Weigh them and equal the mass.

5-Label 5 test tubes (1, 2, 3, 4, 5)

6- Immerse 10 minutes your piece of potato inside the HCL beaker 

7- Immerse 10 minutes another piece of potato inside NaCL beaker.

8- Boil another piece of potato.

9- With a mortar, mash up the third piece of potato.

10- Prepare 5 test tubes as indicated below:

TUBE	TREATMENT
1	Raw potato
2	Boiled potato
3	Potato with HCl treatment
4	Potato with Nacl tratment
5	Mashed up potato

11- Add  5ml H2O2 in each test tube

12- With a glass-marking pen mark the heigh of the bubbles. Measure it with a ruler.

13- Compare the results of the 5 test tubes.

Table with the important parts of this experiment:

Parts:	In this experiment this was...
Independent variable	Treatment
Dependent variable	Bubble’s height
Experimental group(s)	2, 3, 4, 5 (test tube)
Control groups	1 (test tube)
Constant	Concentration of distilled water, the weight of the potato and oxigeneted water

Results

Observations

-We had to put more oxygenated water since almost no reaction occurs.

-The Mashed potato produced more activity.
-The boiled potato and tehe potato with HCl treatment produced less activity.

Questions

1.How did the temperature of the potato effect the activity of catalase? Temperature

desnaturated the catalase.

2.How did the change of the pH of the potato effects the activity of catalase? The change of the pH denaturate the catalase.

3.In wich potato treatment was catalase the most active? Why do you think this was? Mashed potato, because we had broken the cells and the catalase was more quikly.

4.An experiment was performed to test the effect of temperature and pH on the activity of Enzyme X. The following data was collected during the experiment:
a) What is the optimun pH of enzyme X? 8 (maximum activity).
b) What is the optimun temperature of enzyme X? 20 (maximum activity). c) Why do you tink enzyme X has low activity at a pH of 10? Because has been denatured.
d) Enzyme X performs critical life functions. Use the data above to explain why a fever of 40 degrees may be dangerous. Bacause is more lower than the maximum activity.

1.9 Protein identification

Introduction

Biuret's test is a chemical test used for detecting the presence of peptide bonds. Polypeptides as proteins, are chains of amino acids link together by peptide bonds.

A peptide bond can be broken by hydrolysis (the adding water). In organisms, protein molecules called enzymes facilitate the process.

Materials
-7x250mL beaker
-6 test tube
-Test tube rack
-6x10mL pipet

-Mortar
-Glass marking pen
-Gloves
-Goggles
-Milk
-Rice milk
-Egg
-Potato
-Distilleted water
-NaOH 20%
-10 drops of CuSO4 

Objectives

1. Identify peptide bonds.

2.Compare protein concentration in different foods.

Procedure

Firs of all we are going to dilute the protein

1. Add 100ml of distilled water to each 250ml beaker. Lebel them with M(milk), EW (egg white), EY (yolk), P (potato) and RM (rice milk)

2. Separate the egg white and the yolk in another beaker.

3. Smash the potato in a mortar and add some amount of the smashed potato to the P beaker.

Prepare the samples

4. Add 10ml of a dispersion of each food (M, RM, EY, EW and P) to the indicate beaker. Calculate the final concentration. All the groups will use the same dispersion from the beakers.

5. Prepare 6 test tubes (cleand and dry) and lebel (M, RM, EY, EW and P). Add 2ml of the every food dilution of each beaker.

6. Add 2ml of 20% NaOH dissolution. 

7. Shake gently and add 5 drops of CuSO4 in each tube. Allow the mixture 5 minutes. 

8. Note any colout change. Remember that proteins will turn solution pink or purple. 

9. Compare the test tubes.