Jeremy+L.


 * Bio Investigation: Investigating Photosynthesis**


 * Question:**

How do different colors of light affect starch synthesis during photosynthesis?


 * Expectations:**

I would think that different colored light will have different effects on the photosynthesis and starch synthesis of the leaves. I am not absolutely sure what will happen yet, but I think that the darker color the light is, the less starch would be produced in photosynthesis. Photosynthesis may only occur with direct sunlight, so the colored cellophane may prevent the leaves from using photosynthesis. But again, I am not sure, and this experiment will help me find out what truly happens. The Chloroplast is the most important organelle in a plant cell, because it is where photosynthesis occurs. The sugars and starches and all the things that are essential to the plants survival are created in photosynthesis. The different colored light may have an effect on the chloroplast, and if we have time, we may check if it changed in any way.

- Scissors - Black construction paper - Potted plant - Tape - Cellophane of different colors - Test tubes - Forceps - 400-mL beaker - Petri dishes - Iodine solution - Paper towels
 * Materials:**

1. Cut out pieces of black construction paper and different colored pieces of cellophane that is large enough to wrap around a leaf. 2. Cover leaves with the black construction paper and cellophane and tape them on firmly. 3. Leave your plant in a sunlit area for 2 days. 4. Cut off one leaf that was not treated as well as each of the experimental leaves. Roll up each leaf and put them in large test tubes. Label each tube correctly, according to the leaf inside. 5. Fill the test tubes with alcohol so that it covers the leaf. 6. Place the test tubes into a beaker half-filled with water and heat it up. 7. Wait for about 10 minutes and then check if most of the chlorophyll has been removed from the leaves. 8. Remove the leaves from the test tubes and swirl them around in a beaker of clean water, then place them in a Petri dish and cover them with iodine solution. Wait about 2 minutes. 9. Swirl the leaves around gently in the beaker of clean water and then place it on a paper towel. 10. Observe the color and appearance of the leaves and record your observations. - In my experiment, I cover the leaves in Iodine solution and then I rinse them off; I will then be able to see the amount of starch in the leaf - The darker the leaf, the more starch there is in it
 * Procedure:**
 * Results:** (//photos are with my partner: Forrest Zhao)//

Normal leaf: - The normal leaf is the one that we did not cover with any paper or cellophane - Our observations show that the whole leaf is a light shade of brown

Red-covered leaf: - The whole leaf was a light brown; lighter than the normal leaf

Half-covered with black leaf: - Dark shade of brown - The leaf was only half-covered, so I think that the sunlight still got to it, and photosynthesis occurred normally

Yellow-covered leaf: - Mostly covered with dark brown - There were several small patches of light brown

Green-covered leaf: - The top half of the leaf is a lighter color than the bottom - A few white spots on the leaf


 * Discussion:**

My expectations and predictions on what would happen to the leaf were quite correct. The different colors of light had different effects on the leaves. For example, the yellow-covered leaf had a dissimilar appearance from the other leaves; it was dark brown and had several patches of light brown. As of now, I am not sure how to fully explain the reaction of the leaves to the colored light. This creates curiosity, so further experimentation may be done. One thing that I had said did not turn out to be true. I had assumed that the darker color the light is, the less starch would be produced; but the leaf that was half-covered with black turned to be a dark shade of brown. We could go further with this experiment and actually look at the cells of the leaves under a microscope. I can then see if the colored light actually changed the cells or organelles in any way. We may make some interesting and useful discoveries to our experiment.

A chemical that stores and releases energy in a cell. The energy created from the light-based reactions is carried by ATP.
 * Appendix I:**
 * ATP:** //(adenesine=a white, crystalline, water-soluble nucleoside, C10H13N5O4, of adenine and ribose. Tri=three Phosphate=a salt of phosphoric acid)//

A large protein that uses energy from hydrogen ions to bind ADP and a phosphate group to form ATP.
 * ATP synthase:** //(synthase=any of various enzymes that catalyze the synthesis of a substance without involving the breaking of a high-energy phosphate bond)//

Organisms which make their own food, such as plants. All plants are autotrophs, because they make their own food through photosynthesis.
 * Autotroph:** //(autos=self, trophe=nutrition)//

Organelles that capture energy from sunlight and convert it into chemical energy in a process called photosynthesis. By depriving the plant of sunlight, we are disabling the chloroplast’s function.
 * Chloroplast**: //(chloro: green, plast: small structure/body)//

The plant cell’s principle light absorbing molecule. Essential for photosynthesis. Chlorophyll is an important molecule in the process of photosynthesis.
 * Chlorophyll**: //(chloro:green, phyll: leaf)//

An instrument, as pincers or tongs, for seizing and holding objects, an in surgical operation. Forceps can be used to handle hot materials so that you do not burn your hands.
 * Forceps:** //(came from Greek word: ‘formiceps’)//

A nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes. In our experiment, we are using iodine to detect starch in the plant which shows that photosynthesis has happened.
 * Iodine:** //(Iode=rust colored)//

One of the carrier molecules that transfers high-energy electrons from chlorophyll to other molecules. The NADP carries electrons with energy from the sun.
 * NADP:** //(nicotinamide=a colorless, crystalline, water-soluble solid, C6H6N2O, the amide of nicotinic acid dinucleotide= 2 building blocks of DNA/RNA)//

A process in which plants turn solar energy into chemical energy. We are depriving the plant of sunlight to prevent photosynthesis from occurring.
 * Photosynthesis:** (//photo=light, synthesis=putting together)//

The smallest structural unit in a plant that is capable of independent functioning. We are finding out how many plant cells die per square in the leaves of the plant.
 * Plant cell:** //(cell: small enclosed cavity or space)//

Light-absorbing molecules that plants use to gather the sun’s energy. Pigments are light-absorbing molecules which are in the inside of a plant cell.
 * Pigment:**

Clusters in the chloroplast that take in chlorophyll and other pigments. Photosystems, pigments, and chlorophyll are all light-absorbing molecules.
 * Photosystems:** //(phos=light, systema=assembly)//

The dense colorless framework of a chloroplast. The stroma is also inside the chloroplast, it is the space outside the Thylakoid membranes.
 * Stroma:**

Saclike photosynthetic membranes that is the structural unit of the grana in chloroplasts. Thylakoids are inside the chloroplasts of plant cells, they are normally in stacks call granum.
 * Thylakoid:** //(Greek word: thulakos)//


 * Appendix II:**

- Photosynthesis - Chloroplast - Light and Pigments - Light dependent reactions - Light (electromagnetic spectrum)
 * Big Ideas:**


 * Photosynthesis:**

//http://www.biologycorner.com/resources/photosynthesis-overview.gif//

My biological investigation is based on the process of photosynthesis, which all plants go through. The plant takes in energy from the sun, water, and carbon dioxide and creates sugars/starches and oxygen. Plants require the process of photosynthesis to survive. In my experiment, I am trying to discover how different colored light affects photosynthesis.


 * Chloroplast:**

// http://www.olympusmicro.com/primer/java/photosynthesis/javaphotosynthesisfigure1//

The chloroplast is a very important organelle in a plant cell. Without it, it is not possible for photosynthesis to occur. The Calvin cycle occurs inside the chloroplast and this is where the starches are created. The stacks of Thylakoid, the granum, are the main part of the chloroplast.


 * Light and Pigments:**

(Picture does not show up)

Chlorophyll is the main light-absorbing molecule in a plant. There are different kinds of chlorophyll which absorb different amounts of light. It is another thing in a plant that is essential for the process of photosynthesis to occur. The graph above shows the wavelength and the amount of light absorbed by the Chlorophyll a and Chlorophyll b.

//http://www.lcse.umn.edu/specs/labs/images/spectrum.gif//
 * Electromagnetic Spectrum:**

The image above shows the electromagnetic spectrum, which is made up of all the different kinds of light. The light that we are able to see is only a small part of the electromagnetic spectrum. As you can see in the image, different colors have different frequencies and wavelengths. So, different colors will probably have different effects on plants.