Bringing It All to Life
So far we've studied the physical and chemical facts about the ocean: it's a solution of salts in water (what does that mean?), made of moving atoms of various kinds. We've also looked at some atoms (C, H, O) involved in important processes - burning, photosynthesis, and respiration. Now it's time to look at some living things.
Materials
- Styrofoam atoms
- Minimal (a few animals, a bit of algae) brine shrimp aquaria, one for examination by each group
- Camera for TV projection; slide show on CF card
- Brine shrimp eggs, salt water, testtubes/aquaria
- (Perhaps) microscopes, 1 per group
- Observation sheets, 1 per group (minimum)
Activities
- (If necessary) finish modelling of photosynthesis & respiration using styrofoam sphere atoms
- Briefly review modelling of last week (combine with above where appropriate)
- Preliminary comments about observing aquaria SILENTLY: look carefully, write down "inventory" of everything you think might be present (including water, dissolved salt, oxygen, CO2
- Try to draw the interesting things you see...(I'll help w drawing on board)
- SILENTLY write down any questions, you'll get a chance to talk later...
- Distribute aquaria, one per group, start students on Observation and Inquiry phase
- Important questions to make sure arise:
- What are the animals? (Are they animals?)
- What is the green stuff?
- How will they survive if sealed in?
- What care will they require?
- Develop ways of answering these questions; distribute observation sheets
- (If TV available) slide show of artemia characteristics, life cycle, etc.
- If time, set up egg hatchery for observation during week, and include observations on sheets
Discussion
We have a living example of a simple ecosystem, which embodies the back-and-forth processes of photosynthesis and respiration studied earlier on the molecular level. The animals present have some distinctive features, which allow us to classify them by grouping them with similar species. The systems can be used later for experiments to test hypotheses.