Photosynthesis Lab Data Part 2

Tubes A-F Initial (Day 1) Note: they all look yellow near top Tubes A-C after 4 hours (note: Tube B looks bluer than tube A)

Tubes A-F after 24 hours (Day 2) Tubes A-F after 48 hours (Day 3)

Analysis (To be completed if you want to retake the LPA:

• 1. Which results are closest to what should have happened (24 hours or 48 hours)? Provide evidence.

  2. Explain why, after 24 hours, ONLY tube B was blue, but after 48 hours, both B & C were blue. Is this an experimental error? (Hint: Could the fact that the Elodea was so much bigger than the 3 tiny snails been an experimental error? Why?)

  3. Many of the student tubes for Part 1 of the experiment remained yellow, despite having elodea and light. Explain what they did wrong. (Hint: Many of the students did the experiment well and got the expected results).

  4. Some of the 1st and 2nd period tubes with Elodea and light were yellow in the morning, but in the afternoon turned blue, and then were yellow again the next morning. Explain what was (or wasn't) happening at night that caused them to turn back to yellow.