course material

1. Discuss the process and timing of the buildup of oxygen (O2)
#3 Discuss the process and timing of the buildup of oxygen (O2) in the Earth’s atmosphere.
Why is O2 an unusual gas to find in a planet’s atmosphere?
#5 How did the first continental crust form? Discuss in detail.
#10 Discuss the evolution of tetrapods. Define what a tetrapod is and then outline the
timing and appearance of amphibians, reptiles, mammals, dinosaurs, and birds, listing one
major anatomical feature that distinguishes each group.
#12 Discuss the mass extinction event that occurred at the end of the Cretaceous period.
What went extinct? What are some of the possible causes of the mass extinction? What is
the evidence for a large impact at this time?
#13 Discuss the “Snowball Earth” hypothesis. When was this and what was the Earth like
during this time?
Other Questions (handwrite your answers)
What happened at the beginning of the Paleozoic? What happened to end the Paleozoic? Use
Section 22.7 of your textbook for help.
When did the first plants appear on land? What do you think the continents were like before
there were plants growing on them? Use Section 22.7 of your textbook for help and your
imagination.