Reference no: EM132636793

1. Why is the presence of oxygen in the atmosphere good evidence of the presence of life on earth?

2. What would happen to oxygen in the atmosphere if photosynthesis stopped?

3. Westbroek describes the sealed spheres with algae and shrimp, and describes the cycles. Consider an environment somewhere around you - maybe a lake, a river, swamp, the ocean, forest, etc. Describe what organisms play the roles that the algae and shrimp play in the spheres.

4. The sealed spheres are "closed systems" in terms of matter - no physical matter can enter or leave the sphere (though energy can). For the environment above, describe if it is an open or closed system - can matter move in or out? List all the forms of matter (solid, liquid, gas) that can move in or out of the system.

5. Lovelock's Daisyworld model is based on an imaginary planet covered with black and white daisies, that absorb or reflect heat from the sun. In Exploration #2, we will experiment with the Daisyworld model to see how living systems can affect their environment. Look around outside - list at least five different types of ground cover (for example different types of vegetation, soils, rocks, human-built structures, etc.) - and rank them in terms of albedo from high albedo (most heat reflected) to low albedo (most heat absorbed).