In Week Three through Week Eight, you conduct scientific experiments in an online lab environment. The content of the labs vary with each week but the structure remains the same. This week, review your Week Three lab instructions and assignment to become acquainted with the essential elements of each lab. You are not required to complete the actual lab this week, but rather to locate various pieces of information about the labs to help prepare for completion of the labs in Week Three through Week Eight.
Each week you are provided with two appendix documents to complete the lab. One appendix contains all assignment instructions. The other appendix is a lab report in which you answer questions and report your findings. Answer the following questions: Appendix G 1. According to the introduction in Appendix G, what three things must you do before starting the lab? 1.
Don’t waste your time!
Order your assignment!
Print out these lab experiment instructions. A printed copy of these instructions will aid in completing the lab accurately and effectively, because you will not need to switch back and forth between computer screens. 2. Disable your pop-up blocker. LeafLab and the LeafLab Online Notebook will open in new browser windows. If you have a pop-up blocker, they will be blocked. 3. Read the online introduction and background information related to this lab 2. What are the two major sections of the lab assignment? Self-Check Experiment and Exploration Experiment. 3.
What does the red text signify? The answers to the Self-Check Experiment questions are given to you (in red text). Appendix H: LeafLab Report 1. What is the purpose of the LeafLab Report? The LeafLab report document is use to report findings from the LeafLab Exploration Experiment. 2. What are the three major sections of the LeafLab Report? The lab report consists of three sections: Data, Exploration, and Lab Summary. • Data: copy any data, graphs, charts, or notes that you have saved in your LeafLab online notebook into this section. • Exploration: Answer the questions.
The questions in the Exploration section are the same questions in your LeafLab instructions. • Lab Summary: Write a 100- to 200-word summary. 3. What are two points you must address in the lab summary? There are actually four points that we must address, answering each of the following points in a 100-to 200-word summary: • Summarize the general principles and purpose of the lab. • Explain how this lab helped you better understand the topics and concepts addressed this week. • Describe what you found challenging about this lab. • Describe what you found interesting about this lab.
LeafLab The following questions require you to search and review the online LeafLab at http://www. biologylabsonline. com/axia/LeafLab/ 1. In your own words, what is the purpose of this lab? To see how different factors (such as light intensity, light quality, CO2 concentrations, and temperature) affect photosynthesis as measured by how much CO2 is consumed by the leaf cells. 2. What are two objectives of the LeafLab? Demonstrate how photosynthetic rates in different plants can change in response to factors such as light intensity, light quality, CO2 concentration, and temperature.
Compare photosynthesis in C3 and C4 plants. 3. What does the background information tell you about the following: • Heterotrophs Heterotrophs must obtain energy (feed themselves) by eating other organisms or their by-products. They cannot make their own food. • Autotrophs Autotrophs can feed themselves (make organic molecules to support metabolic processes). They use sunlight, CO2, water, and soil nutrients to capture energy in a process called photosynthesis. Some autotrophs use the oxidation of inorganic substances to make organic molecules. Calvin cycle The Calvin cycle is also known as the “dark reactions” or the “light independent reactions”. In the light reactions, energy from sunlight is captured, and stored in ATP and NADPH. These are then passed on to the Calvin cycle. Because the reactions of the Calvin cycle do not directly require light energy, these reactions are known as the dark reactions of photosynthesis. The primary purpose of the Calvin cycle is carbon fixation–the conversion of carbon dioxide into organic molecules such as carbohydrates (such as sugars). 4.
What are two places where you can find help? • The “Help Page” link on the left side of the online LeafLab at http://www. biologylabsonline. com/axia/LeafLab/. The Help Page’s address is: http://www. biologylabsonline. com/axia/LeafLab/help. php • After you start the LeafLab (by starting the Start Lab button) there is a “Help” tab on the Infobar on the top of each page, with explanations and hints. Start the lab by clicking the Start Lab button. Answer the following questions by exploring the equipment, functions, and materials involved in the LeafLab: . What is the purpose of all the lab equipment used in LeafLab? To measure the rates of photosynthesis by measuring the change in CO2 levels in the air that is in the LeafLab chamber. 6. What are two leaves that you can study? Corn, Goldenrod 7. What are two variables that you can manipulate after you choose a leaf and measure its surface area? Gas flow (how many ml of gas per minute), and Carbon Dioxide (CO2) concentrations, in parts per million (ppm) 8. What are two things you can do with the data you collect?
Prepare the data – take the collected data and use that to calculate the photosynthetic rate. Plot the data – use the data collected to plot a graph of photosynthesis rates over varying conditions. Export the data to our notebooks. 9. What function allows you to save data, charts, and graphs? The “Add to notes” copies the data, charts, and graphs to the LeafLab notebook (where we can type additional notes if we want). The “Export Notes” function allows the data to be exported to a web page that we can save.