Announcements GATTACA & Radish work due now. Reminders: PHS notes provided (green pages) & Learning Objectives provided in Course Packet Honors Option: solo research 10 minute Symposium

1. Which of the following statements is a correct distinction between autotrophs and heterotrophs? A. Only heterotrophs require chemical compounds from the environment B. Cellular respiration is unique to heterotrophs C. Only heterotrophs have mitochondria D. Autotrophs, but not heterotrophs, can nourish themselves beginning with CO2 E. Only heterotrophs require oxygen Are you reading, notes, studying? Test your participation

1. The light reactions of photosynthesis supply the Calvin cycle with? A. light energy B. CO2 and ATP C. H2O and NADPH D. ATP and NADPH E. sugar and O2

Short Experiment: Growing radishes from seed

Biology Radish Problem Weighed out 3 batches of radish seeds (each 1.5 g). Experimental treatments: » 1. Seeds not moistened (dry) placed in LIGHT » 2. Seeds on moistened paper towels in LIGHT » 3. Seeds on moistened paper towels in DARK After 1 week, all plant material was dried & weighed. TASK: Predict the (dried) biomass of the plant material in the various treatments.

Predict the final (dried) bio-mass [increase/decrease/no change] A.no change – increase – no change B.increase – increase – increase C.increase – decrease – no change D.decrease – increase – decrease E.None of the above are correct

Results: Weight of Radish Seedlings 1.46 g 1.63 g 1.20 g How do you explain the results? (Remember all treatments started as 1.5g).

When Light Is Absorbed, Electrons Enter an Excited State

Time to capture photons (photosystem football)

How is Oxygen generated in Photosynthesis?

A.CO2 is split into carbon and oxygen B.H2O is split into hydrogen and oxygen C.Light beams oxidize water making O2 D.None of the above

ATP powers everything

Peter Mitchell: Diffusion is the answer!

Paul Boyer: I think it actually twists!

Masasuke Yoshida “Ummm… check this out.”