Test 2 Review: [Class Home Page]
The exam covers Textbook (Jakosky): Pgs 71 - 159, Lecture notes: Early Life 1 - 18, Mars 1 - 17

For Multiple Choice Section
1) Know the four most common biochemical pathways for life to obtain energy.
2) What's different between hetero and auto-trophs? Chemo and Photo-synthetic?
3) Where might you find: Barophiles? Thermophiles? Psychrophiles? Endoliths or Halophiles?
5) How might complex organic molecules have been naturally made in the early Earth?
6) What is the Miller-Urey Experiment? Why is it probably not applicable to early Earth?
7) What can DNA tell us about evolution?? about the oldest common ancestor to all Earth Life?
8) What was the earliest life likely like? What evidence is there for this `educated guess'?
9) What are Hydrogen bonds? What affect does it have on the behavior of water?
10) What unique characteristics of water make it the likely basis for ALL life?
11) Why is ALL life probably Carbon-based? What important characteristics does C have over Si?
12) What is the minimum mass for a habitable planet? Why? What makes for a habitable planet?
13) How is Mars similar to Earth? How is Mars different from Earth? (orbit, seasons, atmosphere, etc)
14) Is there water on Mars presently? Where is it known to exist? Where is it thought to exist?
15) Mars' surface can get very warm, yet liquid water is not stable on Mars. Why?
16) What evidence suggests sub-surface liquid water? How so, if it can't exist on the surface?
17) How is Volcanism on Mars different from Earth? Is there Plate Tectonics? Why/Why not?
18) What is so special about Olympus Mons? Why did it get so big? Is it currently active?
19) How where the SNC meteorites first identified? How were they linked to Mars?
20) What where the Viking Missions? Know the 4 tests. What was the most important finding?
21) What was the importance of the Mass Spectrometer experiment on the Viking Mission?
22) Why are most meteorites found in Antarctica? How do rocks from Mars get to Earth?
23) What are PAHs? What was unusual about the PAHs found in ALH 84001?
24) What size where the Martian fossils found on ALH 84001? What's wrong with that?
25) What is Occam's Razor? How can it be argued both for and against life on Mars?

Concepts for Essay Section I will ask you exactly ONE of these sets of questions from the following topics. You'll need to know them all to be fully prepared. Full sentences are required, though tabular presentations are fine, too.

[The Tree of Life.] What three domains make up the tree of life? What has genetic studies told us about life on Earth? Where did we all come from?

[Water.] Name at least 3 important and unique characteristics of water and how this has been important to water-based organisms and life on Earth. Why do we think extraterrestrial life will require liquid water?

[Viking Mission.] List and descrbe the four experiments (three biological, one chemical) that were done during the Viking Mission. What was their result? Which experiment was most definitive and why?

[Extremophiles.] Give several examples of these organisms. What is their connection to the Universal Ancestor and early life? What is important about them in considering life on other planets/moons?