Text of Photosynthesis & Respiration Lab What is the relationship between photosynthesis and respiration?
Photosynthesis & Respiration Lab What is the relationship between photosynthesis and respiration? Slide 2 Part 1 Investigative Question: What will happen to a carbon dioxide solution of CO 2 and water if a water plant is added? Write your hypothesis: If _______________ then__________ because__________________________. *Get signed off by your teacher Slide 3 Materials Test tubes x 4 Stoppers x4 Elodea (2cm) Foil Test tube rack Bromothymol Blue Lamp Slide 4 The Acid-Base Scale & Bromthymol Blue 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Most leastleastmost Acidic Neutral Basic 6 7 8 Water CO 2 in water No CO 2 in water, Regular tap water Distilled water Slide 5 Protocol 1.Label your test tubes with your names and the letters A, B, C, and D. 2.Fill each 1/2 full with distilled water. 3.Add 1 dropper of acid/base indicator (bromothymol blue) A B C D Per5Per5 Per5 Per5 NameNameName Name Slide 6 4.Place a straw into Test Tube A. 5.Gently blow into the solution until it starts to turn yellow- STOP IMMEDIATELY when you see a change in color!!! STOP! A A Slide 7 6.Repeat Steps 4 & 5 for all test tubes& place 1 sprig of elodea into test tubes A & C. A B C D Per5Per5 Per5 Per5 NameNameName Name Slide 8 7. Then place stoppers on all test tubes. A B C D Per5Per5 Per5 Per5 NameNameName Name Slide 9 8. Wrap Test Tubes C & D with foil so that no light can get in. A B C D Per5 Per5 Name NameName Name Slide 10 9. Place all test tubes on a test tube rack or holder and place in the tray that will go under a light. A B C D Per5 Per5 Name NameName Name Slide 11 Predictions: Test Tube Color after 24 hours pH = ?Why do you think this? A B C D Slide 12 Original Data Table Test Tube Color start (pH = 6-, 7, 8+) Color after 24 hours (pH = 6-, 7, 8+) A B C D Slide 13 Class Results: Color (pH) changes for Day 1 GroupTube ATube BTube CTube D 1 2 3 4 5 6 7 Mode: Slide 14 Part 1- Data Collection 1.Observe the results after 24-48 hrs. 2.Record data on data table. Slide 15 Part 2 Investigative question: What is the role of light in photosynthesis? What might happen if the tinfoil was switched to test tubes A & B? Write your hypothesis: If _______________ then__________ because__________________________. *Get signed off by your teacher Slide 16 Identify the following in this inquiry: The manipulated variable _____________ Responding variable_________________ Controlled variables _________________ ____________________ Experimental control _________________ Purpose of the experimental control _____ __________________________________ *Get teacher signature Slide 17 10. Wrap Test Tubes A & B with the foil so that no light can get in. C D A B Per5 Per5 Name NameName Name Slide 18 11. Place all test tubes on a test tube rack or holder and place in the tray that will go into the greenhouse. C D A B Per5 Per5 Name NameName Name Slide 19 Part 2 Data Table: pH after light/dark conditions reversed Test Tube Color after 24-48 hours pH = ?Why? A B C D Slide 20 Part 2 Data Collection Record your results in your data table. Slide 21 Analysis Questions Part 1: 1.Explain what happened to the pH of the solution for Test tube A. Why did you get these results? 2.How were these results different than test tube B? Why? 3.How were they different than C? Why? 4.And D? Why? Slide 22 Analysis Questions Part 2 & 3: 1.What results changed as a result of switching the foil on the test tubes? 2.Why do you think this happened? 3.What is the role of light in photosynthesis? 4.Can plants do respiration? What evidence supports this? 5.What changes would you make to improve this lab and why?