Photosynthesis Virtual Lab

Question:  What is the effect of temperature on the rate of photosynthesis

Hypothesis: If higher temperatures make reactions faster, then higher temperatures will increase the rate of photosynthesis.

Independent variable: temperature

Dependent variable: amount of oxygen bubble present

Control: 10 degrees centigrade

The experiment will have 30 second trials. The temperatures will be 10 degrees, and 40 degrees.  All trials will have white light, with 25 light, and 1 scoop of dissolved carbon dioxide.

Degrees ( 0C)	Amount of Bubbles (Measure of Oxygen)
	Trial 1	Trial 2	Trial 3	Average
10	9	9	9	9
25	27	28	30	28 1/3
40	22	21	22	21 2/3

Conclusion

In this lab, I asked, “What is the effect of temperature on the rate of photosynthesis.” I found out that a higher temperature does increase the rate of photosynthesis, but when the temperature increased too much, then the rate of photosynthesis decreased. I found out that at 10 degrees centigrade, the average amount of bubbles in 30 seconds., which quantifies the rate of photosynthesis, was 9. At 25 degrees centigrade, there was an average of 28 ⅓ bubbles per 30 seconds. At 40 degrees centigrade, there was an average of 21 ⅔ bubbles per 30 seconds. This was expected, because the enzymes that drive photosynthesis cannot work at too hot or too cold temperatures. If the temperature is not ideal, then the enzyme will denature, and photosynthesis will not work as fast.

This lab was done to demonstrate the effect of temperature on photosynthesis. From this lab, I reviewed the concept of enzymes and photosynthesis. The lab demonstrated how temperature can denature enzymes and slow down reactions such as photosynthesis. I also learned how to design a simple experiment and identify parts such as controls and variables. Based on my experiences with this lab, I can easily design another lab and identify its parts. I could also test a different variable, such as amount of light.

Unit 3 Reflection

    This unit was all about the cell. We first learned about the cell, then how the cell evolved, We also learned what was in a cell, movement in the cell, and photosynthesis and cellular respiration. The main idea of this unit was that the cell is the most basic unit of life.
    In the first vodcast, we earned about how the cell was discovered and the cell theory. We then learned about the levels of organization of life and the differences between prokaryotes and eukaryotes. Finally, we learned and that macromolecules are present in cells and where. In the next vodcast. we learned about membranes. We found out about their structure and function and the different methods that molecules use to get in and out of the cell. In the next vodcast, we learned about osmosis and diffusion. We reviewed some terms and learned about what happens when water leaves and enters the cell. In the following vodcast, we learned how proteins are made and other various functions of cells. We briefly talked about mitosis, cellular respiration, and photosynthesis. In the next vodcast, we toured the cell. We learned about the different functions of organelles and where they are located. We also looked at the differences between plant and animal cells. Next, we learned about the story of cells. We learned how cells gradually evolved to be more complicated. The following vodcast was about photosynthesis. We learned what photosynthesis is, its products and reactants, where it takes place, and how it is performed. Finally, we learned about cellular respiration. We learned about the exact things about it as we did for photosynthesis.
     This unit was slightly difficult because there was a lot of concepts. There were a lot of different ideas and concepts. Also, there was a lot of memorization, especially in the photosynthesis and cellular respiration vodcasts. I understand most of the concepts, but I have trouble remembering all the terms and details of them. In addition, we did a lot of labs. I learned various skills from them, such as team work and how to use a microscope. From these experiences, I can do more types of labs.
     I want to learn more about the cell. I am interested in how cells communicate with each other. I am interested in learning more about organelle functions and functions of the cell.

Plant Cell

Animal Cell 

Egg Diffusion Lab

     In this lab, we first put two eggs in vinegar and left them for 48 hours. This was to insure that that the shell of the egg broke down. Next, we measured the circumference and the mass of both eggs. We submerged one egg in dark corn syrup (sugar water) and another in deionized water. We left the eggs in their respective solutions for 48 hours. After 48 hours, we measured the circumference and the mass of both eggs.
   Looking at the class data, the mass and circumference of the egg in sugar water went down. On average, the mass decreased by 51.7% and the circumference decreased by 23.67%. This was because of diffusion. There was more solute, sugar, than solvent, water, in the outside of the egg. The opposite was true inside the egg. Diffusion involves the moving of stuff from high to low concentration. The solute cannot move through the membrane, so water from the egg had to move out. 
     A cell's membrane changes as a result of its external environment because of its semi-permeable membrane, and forces such as passive diffusion acted on it. When we put the egg in vinegar, there was no change because the egg shell prevented stuff from moving out. However, once we put the egg in deionized or sugar water, the egg shell was gone because the vinegar caused the shell to erode. When we put the egg in sugar water, water diffused out, When we put the egg in deionized water, water diffused into the egg. 
     This lab demonstrates the biological concept of diffusion. In the egg with sugar water, there was a low concentration  of water outside and a high concentration inside. The solution was hypertonic. In order to keep the concentration the same, water needed diffuse out. Since sugar cannot move through the membrane, only water could diffuse out. With the egg in deionized water, there was a high concentration outside and a low concentration inside. The water diffused in, and as a result, the egg got bigger. 
     This lab can be applied to real life solutions. Have you ever wondered why water is sprinkled on vegetables? The principles of diffusion easily explain this. Since there is less water on the outside of the cells than on the inside, through diffusion,water will move into the vegetable cells, expanding them. This creates the impression of a larger vegetable. Also, roads are sometimes salted to melt ice. Salt mixes with the water to form salt water. This effects plants on the side of the road. Since the water on the outside has salt, water diffuses out of the plant to balance it out. This results in shriveled up plants. As you can see, diffusion is everywhere.
     Based on this experiment, I would want to test whether fruits with a thin skin, such as apples perform diffusion. The shell or skin sometimes blocks diffusion, but what happens if the skin is thick. The setup would be the exact same thing. A whole apple would be placed in corn syrup and a whole apple would be placed in deionized water. 

Control (DI Water)

Group #	2	3	4	5	6	7	AVG
% Change in Mass	-0.54	-1.47	10.5	.74	-4.2	-5.1	.176
% Change in Circumference	-2.89	0	2.1	0	-12.9	-4	.201

Sugar Water

Group #	2	3	4	5	6	7	AVG
% Change in Mass	-49.77	-55	-52	-44.6	-52.4	-56.7	-51.7
% Change in Circumference	-23.6	-28	-20.6	-29.4	-37.5	-37.5	-23.6

Before

After

Egg Cell Macromolecule Lab Conclusion

           In this lab, we asked the question," Can macromolecules be identified in an egg cell? We found out that in the egg membrane, polysaccharides and lipids were found, in the egg white, polysaccharides and proteins were found, and in the egg yolk, monosaccharides, polysaccharides, and lipids were found. We figured this out through indicators. If benedicts solution and boiling water are placed in a solution containing monosaccharides, the benedicts solution will change from blue to green or orange. If iodine is placed in a solution containing polysaccharides, the the sample will change from brown to black. If Sudan III is placed in a solution containing lipids, then the sample will turn from red to orange. If sodium hydroxide and copper sulfate are mixed into a solution containing proteins, the sample will turn from blue to purple. This evidence supports my claim because when the indicator was added, the sample would turn positive for the macromolecules that I listed.
      However, our data was unexpected because some of the macromolecules that were suppost to be present were tested negative for. A possible error that could have caused this was because the indicators were not properly mixed into the different parts of the egg. For example, there was suppost to be protein in the egg yolk, but since the indicator was blue and the yolk was yellow, it looked green because they were not properly mixed. Another error was that not enough indicator was put it. This would have led to not a full color change. Since the color did not change enough on various tests, we marked them not having a particular macromolecule, while in reality they could have if more indicator was put in. In order to stop these problems, the indicator needs to be put in greater amounts and mixed better.
     The purpose of this lab was to find what macromolecules are present in the different parts of an egg. This lab relates to what we learned in class because many of the places that macromolecules we were taught that appeared also were tested positive for in the lab. For example, we were taught that lipids are formed in membranes. In the lab, the egg membrane tested positive for lipids. We essentially verified what we were taught. Finally, this lab could be applied to other labs by using the same indicators to test for macromolecules in other foods.