Name(s): ______Block: ______Date: ______
Photosynthesis Virtual Labs
Lab #1: bit.ly/pholab
Which colors of the light spectrum are most important for plant growth?
Instructions:
· Read the summary in the side bar which explains how colors of light affect plant growth.
· Read the procedure. Perform your experiment(s) and record your data in the table, make a graph, and answer the questions. Test all three types of seeds.
Data Table Title: ______
***Please note these are average heights and you measured between 3 and 6 plants!!***
Questions:
1. What was your independent variable?
2. What was your dependent variable?
3. Identify 3 variables did you controlled in your experiment.
4. What conclusions can you draw about which color in the visible spectrum causes the most plant growth?
5. Explain any differences or similarities you found among types of seeds.
6. Given that white light contains all colors of the spectrum, what growth results would you expect under white light?
Lab #2: http://www.kscience.co.uk/animations/photolab.swf
How do different factors affect the rate of photosynthesis?
In this lab, you will be experimenting with how different variables affect the rate of photosynthesis.
1. Set the thermometer to 25°C (Room Temperature) and the light intensity to 20.
a. What were the bubbles per minute at this setting? ______bpm
b. Now increase the CO2 available to the elodea. What were your bubbles per minute? ______bpm
c. Based on your data, how does the amount of available CO2 affect the rate of photosynthesis?
2. Keep your settings from #1 (25°C, light intensity of 20, increased CO2).
a. Now increase the temperature to 40°C. What were your bubbles per minute? ______bpm
b. Based on your data, how does an increase in temperature affect the rate of photosynthesis?
3. Return to your settings from #1 (25°C, light intensity of 20, increased CO2).
a. Now decrease the temperature to 10°C. What were your bubbles per minute? ______bpm
b. Based on your data, how does a decrease in temperature affect the rate of photosynthesis?
4. Design an experiment to test the effects of varying amounts of light on the rate of photosynthesis. In the space below, create a data table and graph to show the results of your experiment. Make sure to list any controlled variables.
Based on your data, what is the effect of light intensity on the rate of photosynthesis?
5. Alter the variables in order to determine which combination leads to the highest rate of photosynthesis. Which combination of settings produced the highest number of bubbles per minute?
a. Temperature: ______b. Light: ______c. CO2: ______
Lab #3: http://www.classzone.com/cz/books/bio_07/resources/htmls/virtual_labs/virtualLabs.html
How is carbon transferred through different organisms in the biosphere?
Click on Carbon Transfer Through Snails and Elodea. Read through the directions and complete this lab, answering the lab notebook questions (in bold) in the appropriate locations on this worksheet below. When indicated, enter the lab set-up as indicated below to assist you.
(NOTE: You will have to make entries about your observations and predictions in the online lab notebook in order to advance through the online experiment. Just put ‘X’ in all of the spaces to move through. Your answers are written on this sheet.
Question: How does carbon dioxide cycle in aquarium water through snails and Elodea?
Design an Experiment:
1. Measuring CO2: How will you measure the level of CO2? (Hint: look at the bottom right corner of the lab bench graphic!)
2. Independent variable:
3. Control:
(Your control should be a test tube without any Elodea/Snails in it, so that you can determine what effect the Elodea/Snails have on the levels of carbon dioxide in the test tube.
4. Identify the set-up for each tube, using Tube #1 as your control:
Tube #1: ______
Tube #2: ______
Tube #3: ______
Tube #4: ______
Tube #5: ______
Tube #6: ______
Tube #7: ______
Tube #8: ______
Note: You don’t have to use every tube…it depends on your experiment.
Data:
The Effect of Different Organisms on the Amount of Carbon Dioxide in a Closed System
Test Tubes / Location / Contents / Starting Color / Predicted End Color / End Color (Actual)1 / green
2 / green
3 / green
4 / green
Test Tubes / Location / Contents / Starting Color / Predicted End Color / End Color (Actual)
1 / green
2 / green
3 / green
4 / green
Note: Depending on your experiment you may only use the top half of the table. The two tables are for light and dark if you choose to test both conditions.
Analyze and Conclude:
1. Why did the color of the bromthymol blue change?
2. What was the importance of a control in your experiment? Why did you put a stopper on the test tubes?
3. When you began the experiment, was there CO2 in the water? How do you know?
4. In the test tubes that contained the Elodea, where did the CO2 go?
5. Which gas did the snails release? What evidence supports this?
6. Do plants perform cellular respiration? What evidence supports this?
7. Explain why the snails and Elodea are interdependent and rely on each other for survival in this closed system.