Study Questions - Origin of Life
Readings - Lane
1. When did the solar system form, and why are there no earth rocks that old?
2. Explain the realtionship between stratification of earth elements, vulcanism, and the creation of the first atmosphere held by the earth's gravitational field.
3. What two pieces of evidence suggest that the early atmosphere contained no oxygen gas? (one is atmospheric, one is geologic).
4. When did O2 begin to accumulate in the earth system, and how do we know this?
5. Why didn't oxygen increase dramatically after that? In other words, what happened to most of this early oxygen has? Where is it now?
6. When did the first eukaryotes evolve? What ecological roles did bacteria play for the first 1/2 of life's history?
7. When did the first multiecllular animals evolve? Why did it take so long for eukaryotes and multicellular life to evolve? What evolutionary hurdle had be jumped?
8. About 600mya, the fossil record expanded dramatically with the "Cambrian Explosion." Why do we see this dramatic increase in the number of fossils? Provide an ecological reason.
9. List the three requirements of a living system.
10. How could membranes form spontaneously?
11. Explain the process of "reverse evolution" of metabolic pathways.
12. Describe the "RNA world" hypothesis.
13. What characteristics of RNA suggest they may have been ancestral to DNA?
14. If RNA was the first genetic system, what two reasons favor the incorporation of DNA? How could this occur?