*** Version 1.0, 2008 Apr 9 ***
Astrobiology Exam #2 Study Guide
Exam Date: Friday April 11

Bring a clean, uncrumped ParSCORE Student Enrollment form (the larger 6"x11"pink form), some #2 pencils & an eraser. This is a "closed-book exam". No calculators/PDAs/PalmPilots/cell phones/GPS/ipod/mp3 players/etc allowed; slide rules are ok.

** Fill out your name and Red ID on the ParSCORE form before the exam starts. Be sure to put your Red ID on both sides of the form. Also, fill in the bubble for "Test Form A" and "Exam #002". Don't bother with the phone number or code.
** Be sure to fill out your ParSCORE form correctly! You will lose points on your exam for errors on the scantron form (1 point per error). Common errors include:
. putting an extra zero in front of your Red ID
. filling in wrong bubble on your Red ID
. Red ID is too faint
. filling in two answers because your writing was sloppy
. not erasing an answer fully

Exam will consist of 50 multiple choice questions.

This exam covers all material discusssed and assigned since Exam #1:
+ Lectures
+ Lecture notes
+ Reading assignments in the Textbook
+ Reading assignments in the Course Reader
+ Written homework assignments
+ Examination of the NEO and SpaceWeather.com webpages.
The exam will focus on material since the first midterm, but of course certain concepts will carry over (habitable zones, spectroscopy, speed of light, temperature, AU, angular momentum, stellar evolution, etc.).

The follow chapters in the textbook are covered on this exam:
Ch 3.4; Ch 4; Ch 5; Ch 6
 In the Course Reader, the following are important for this exam:
The Search for Extraterrestrial Life (C. Sagan)
Terrestrial Evolution (by N. Evans)
The Origin of Life on the Earth (L. Orgel)
Meet the Relatives (from New Scientist)
The class lectures should be your primary source of information.
The on-line notes are very helpful, but are incomplete. The textbook material is very important. Make sure you have done *all* the homework, including the homework that you don't have to turn in (textbook, Class Reader, and web page reading assignments). Roughly 10% of the exam will be based on the material from the Class Reader, especially topics related to biochemistry.
Know the definitions of the biological terms on page 152-153
____________________________________________________________________

Here is a list of some material that you will NOT be responsible for knowing for this midterm exam:
** Skip all of the "Movie Madness" sections
- You do not need to know any molecular structures. For example, you will not be asked to know the molecular difference between adenine and guanine. You do need to know what these molecules do though!
- You do not need to know the location of the elements in the periodic table, or their chemical bonding properties, except for carbon.
- You don't need to know the names of specific bacteria species [such as Streptococcus mitis (the bacteria that survived on the Moon) or Helicobacter pylori (the ulcer-causing bacteria that dwells in the stomachs of half of the people on Earth), or Thiomargarita namibiensis ("the sulfur pearl of Namibia")], with the exception of that particular bacteria that can withstand huge doses of radiation....
- Do not confuse specific species with the types of extremophiles; you should know the different types (classes) of extremophiles e.g. thermophilic, halophilic, etc..
- You will not need to know the values of any physical constants except the speed of light "c".
- You will not need to know exactly how many meters are in a parsec or how many meters in an AU, or how many meters in a light year. But you need to know the definition of an AU, light year, parsec (the definition, not the actual numbers!), meaning of moon, star, isotope, principles of spectroscopy, etc.
- You don't need to know anything from the following web pages for this exam (but you certainly will for the final!):
NASA's Mars Exploration Program website; NASA+ESA Cassini/Huygens websites; and the "Google Mars" website.
- You do NOT need to memorize the genetic code! If this information is needed, I will put a copy of the table in the exam itself.
- You do not need to know about Darwin's finches (fig 5.2)
__________________________________________________________________________

Some typical exam questions:

In his Scientific American article, Carl Sagan discusses an important biomarker signature of life, detected by the Galileo spacecraft. Which of the following is a indicator of life?
A) the presence of water vapor in the atmosphere
B) the presence of molecular oxygen in the atmosphere
C) the presence of tholins in the atmosphere
D) the presence of carbon dioxide in the atmosphere
E) the presence of nitrogen in the atmosphere

A WWWeb site reports the discovery of "a 4.378119104 billion year-old fossil of a bacterium." You are highly skeptical. Why?
A) This is older than the Earth.
B) Dating of rocks is nowhere near that precise.
C) Rocks that old are practically non-existent on Earth due to crust recycling by plate tectonics (subduction).
D) choices B) and C)
E) choices A), B), and C)

How many different types of nitrogenous bases (or nucleotides) are used in DNA? How many of these bases are in a single codon (the fundamental unit of the genetic code)?
A) 2; 2
B) 4; 2
C) 4; 3
D) 20; 3
E) 20; 4

Amino acids are the chemical building blocks (monomers) of what type of molecule?
A) cellulose, starch, and/or glycogen
B) nucleotides
C) DNA and RNA
D) proteins
E) ATP

Which of the following is true about the isotope carbon-13?
A) It has 13 protons in its nucleus.
B) It is radioactive and has a half-life of about 5730 years.
C) It is formed by collisions between cosmic rays and gases in the Earth's atmosphere.
D) It has 13 neutrons in its nucleus.
E) It can be used to help deduce when life started on Earth.

Some "be sure to know these" hints:
- What is "CHONPS"?
- What does "temperature" really measure?
- What are monomers and polymers?
- Why are amino acids important?
- What is "endosymbiosis"?
- What is a chloroplast? What is a mitochondria? What is a ribosome?
- Why we think all life on Earth had a common ancestor?
- What are the key things essential for life (as we know it)?
- What are extremophiles?
- What makes a hypothesis a scientific hypothesis and not just an idea?
- Approximately what is age of the Earth? How do we know?
- What are three largest divisions (domains) of terrestrial life?
- What is a "NEO"? How many are there?
- What is the K-T boundary? What was the K-T event?
- What do the letters "UFO" stand for?
- What is the habitable zone? In what cases is it irrelevant?
- How does the habitable zone change with time? With the star's spectral type?
- What is the difference between infrared, ultraviolet, radio and X-rays?
- What is the difference in meaning between the words "galaxy", "solar system", and "universe"?
- What are asteroids?
- What are meteorites?
- Who was Alfred Wegener?
- Who is Carl Woese?
- What did the father and son Alvarez team discover?
- Why won't deep-sea water boil if its temperature is 400 degrees C?
- What does it mean to say "It has been, and always will be, the `Age of the Bacteria'"?
- What is a "potentially hazardous asteroid"?
- What are the 3 major pieces of evidence for ancient life on Earth?
- What is DNA and RNA?
- What is the "RNA World" hypothesis?
- What are proteins used for, and how are they made?
- What is a codon?
- What is a gene?
- What is evolution and what is natural selection?
- What is molecular "handedness"?
- What are the functions of proteins?
- What is subduction?
- What is a "black smoker"?
- What is plate tectonics?
- What is a stromatolite?
- What is the C-12 / C-13 isotopic signature of life?
- What is a "domain"?
- What is an extremophile?
- What does the word "archaea" signify?
- What is a procaryore? What is a eucaryote?
- What is a sedimentary rock?
- What is a thermophile? A halophile?
- What is a spore?
- What is the Tree of Life?
- What is a mutation?

More questions to help you prepare:
What is the "habitable zone"?
What is the Principle of Occam's Razor?
"Extraordinary claims require extraordinary evidence" - What does this mean?
What does it mean when we say something is "necessary but not sufficient"?
What is "chicxulub" all about?
What does the the term "global winter" mean?
What do we mean by "space weather"?
What are carbonaceous chondrites? Why are they important in astrobiology?
What role do supernovae play in the origin, evolution and development of life?
If someone says, "But it's only a theory...", why does that make no sense to a scientist?
What can you use spectroscopy for?
Good Luck!