1. Compare and contrast the dew collectors and the stillsuit in terms of (1) purpose, (2) how they work, (3) energy source, (4) their use in real life.

2. Compare and contrast the sandworm and the camel in terms of desert adaptation. Include (1) water use, (2) heat avoidance, (3) digestive chemistry.

3. Based on your graph of water saturation: Suppose air that is raining at 40 degrees F warms up to 80 degrees F. What is the percent water saturation? How does the air feel?

4. Sketch the main carbon cycle in Earth's biosphere. Include cycling of carbon dioxide, water, and other necessary components. Explain how the cycle differs from that proposed for Dune.

5. Suppose Dr. Wu measures the phylogeny of the dinosaurs he has cloned. The table shows the percent relatedness of all pairs of dinosaur species. If the dinosaur mutation rate is 0.13% per million years, draw a tree of phylogeny (divergence) including all the species.

6. Compare and contrast the ocean ecosystems of the upper water layers versus the ocean floor. How do they compare with respect to (1) available nutrients, (2) source of energy, (3) producers and consumers, (4) source of oxygen?

7. Explain how the Sharers used lifeshaping of animals and plants to accomplish aims that we accomplish with machines.

8. Suppose you measure the hydrogen ion concentration of a soil sample (1.2 x 10^-5 Molar) and of lemon juice (8.3 x 10^-2 Molar). Are they acidic or basic? Which has greater acidity?

9. The main weak acid in citrus fruits is citric acid (K_a = 7.5 x 10^-4). If an orange contains 10^-3 Molar citric acid, what is the pH of the orange juice?

10. Compare and contrast the adaptation of Fremen and of Sharers to their respective environments. Which adaptations are genetic, and which are cultural? Which adaptations involve cooperation with other life forms? How do the Fremen and the Sharers use their adaptations to resist foreign invasion?

11. Describe a typical ecosystem of each type: intertidal zone (marsh); coastal shelf; open ocean; sea floor and vent community. Explain how the types are similar, and how they differ. How do they relate to the ecosystem of Shora?

12. Describe three different kinds of desert ecosystem. How do they relate to the desert ecology of Dune?

13. Explain how ecosystems function. How do they recycle nutrients? How do they maintain energy?

14. Explain how symbiosis works in ecosystems. How does evolution favor symbiosis? How do symbionts maintain their partnership without each destroying the other?

15. Explain how water is used by the human body. How much is consumed, and in what forms is it excreted? Where does all the water we excrete end up? Where does the water we drink come from?

16. The Fremen face a problem in the "watering" of Arrakis. Where does the water come from? What will happen if they succeed? How do their problems relate to ours in our use of water in agriculture?

17. Explain why and how evolution generates many divergent species of a given class of life form. Why does evolution not produce the "one" fittest species?