Team+3

Team 3: Eva, Whitney, Lexi, Liz

Part A
 * Title**: The Effect of Temperature on Dissolved Oxygen of Water


 * Purpose**: The purpose of this lab is to test the effect of temperature on the saturation of dissolved water in temperatures.


 * Hypothesis**: As water becomes warmer, its ability to hold oxygen decreases; therefore if the algae culture is exposed to different temperatures, then it will hold more dissolved oxygen at colder temperatures.


 * Materials**: Please refer to Activity A of the Dissolved Oxygen and Aquatic Primary Productivity lab handout.


 * Methods**: Please refer to page 1 of the Dissolved Oxygen and Aquatic Primary Productivity lab handout.

Measurements of Dissolved Oxygen at Different Temperatures __Degrees__ Celsius || Group DO || Group % Saturation ||
 * Data and Observations:**
 * Temperature
 * 10 || 11 ppm || 99% ||
 * 20 || 9.5 ppm || 104% ||
 * 30 || 9.25 ppm || 122% ||


 * I can't figure out how to make a graph of this!


 * Analysis**: After measuring the amount of dissolved oxygen in the water at each temperature variable, the results indicated that the 10 __degrees__ Celsius water held the most oxygen at 11ppm. The 20 __degrees__ Celsius water held the next highest amount of oxygen at 9.5 ppm, followed by 30 degrees Celsius. These results indicate that water holds the most oxygen at colder temperatures. This may be because the gases in cold water have less kinetic energy and are less likely to escape the liquid as a gas, unlike the gases in warm water.


 * Conclusion**: Since the algae cultures were exposed to different water temperatures, more dissolved oxygen was held at at colder temperatures. The hypothesis was verified with the data found in the experiment previously done.

Part B
 * Title**: The Effect of Light on the Oxygen Production of //Choella//


 * Purpose**: The purpose of this lab is to test the effect of varying degrees of light on the oxygen production (photosynthesis) of Choella and then use this data to calculate net productivity, gross productivity, and the loss of oxygen during respiration


 * Hypothesis**: If the cultures of algae are placed under various degrees of light, then the cultures exposed to the brightest light will contain more dissolved oxygen due to the fact that photosynthesis will be occurring faster producing more oxygen.


 * Materials**: Please refer to page 5 of the Dissolved Oxygen and Aquatic Primary Productivity lab handout.


 * Methods**: Please refer to Activity B of the Dissolved Oxygen and Aquatic Primary Productivity lab handout.

Measuring The Dissolved Oxygen Under Different Light Conditions
 * Data and Observations:**
 * Bottle || DO || Net Productivity || Gross Productivity ||
 * Baseline (Initial) || 9.9 || --- || --- ||
 * Dark || 3.6 || --- || --- ||
 * Light (0 Screens) || 18.6 || 8.7 || 2.4 ||
 * 1 Screen || 19.7 || 9.8 || 3.5 ||
 * 3 Screens || 17.5 || 7.6 || 1.3 ||
 * 5 Screens || 9.1 || -0.7 || -7 ||
 * 8 Screens || 8.3 || -1.6 || -7.9 ||
 * I can't figure out how to make a graph of this either!


 * Analysis**: After measuring the amount of dissolved oxygen in the water of the varying samples, then determining the new productivity and the gross productivity at the different light intensities, the results show that the algae exposed to the light with only one screen was the most productive sample. The next most productive sample was the algae culture with no screens hindering the light penetration. Both samples had the highest net and gross productivity. This means that the samples exposed to the most light without the hindrance of screens were the most productive algae cultures. This is likely because they are undergoing photosynthesis at a higher rate, since more light is available to power the light reactions.


 * Conclusion**: Since the algae cultures were placed under varying degrees of light, the cultures exposed to the brightest light contained the most dissolved oxygen. The experiment verified the hypothesis previously made.