Astr 310 Astrobiology - Final Exam Study Guide
Monday, May 11, 10:30-12:30
THIS IS THE FINAL VERSION FOR THE 2020 SPRING SEMESTER
The final exam will be administered via Blackboard and will be
available
only during the normal final exam window: 10:30 am - 12:30 pm.
You will need to have
Zoom running with the chat messaging window visible, and the
video and audio turned on so I can see and hear you as you take the exam.
(Turn your speaker volume down so you do not get distracted.)
Failure to be on Zoom will result in a zero grade on the exam.
The Zoom meeting will be recorded. You will need a password
for the exam, and a different password for Zoom.
During the exam, you will be able to see only one question at a time,
and you will NOT be allowed to go back and alter an answer.
{My apologies for these somewhat draconian measures, but
I have been advised to increase anti-cheating techniques.
I understand that these conditions make testing harder, and the
curve on the exam will attempt to compensate for that.}
Please read the .pdf document
General Advice for Students Taking an Exam on Blackboard.
In particular, note that you are strongly advised NOT TO USE THE
CHROME BROWSER to take the final exam. Student have recently
reported major problems with multiple-choice questions and Chrome.
This is an open-book exam. The textbook, class notes, your
notes, your old homework, and a calculator are allowed.
You can use a computer (or tablet) to view the on-line
textbook, the class notes, and your own notes.
Don't worry about using a computer while taking the exam. It
is easy to tell the difference between searching the textbook index for
a word or two, verus typing the questions into Google or texting
someone! Clicking with your mouse is not going to raise any suspictions,
but using your cell phone certainly will.
You may not use the internet (or any search engine like Google) to look up
information that helps answer to any question and you may not ask anyone
else for assistance with the exam. Like any final exam, cheating in any
form (including using a copy of an old final exam) is strictly
prohibited and will result in: (i) a zero grade on the final exam; (ii)
a letter grade deduction in the course grade; (iii) loss of all extra
credit points); and (iv) reporting the crime to the Office of Student
Rights and Responsibilities for additional disciplinary action, which
may include dismissal from the University.
During the exam, turn off the volume in your speakers, but do not mute the
microphone. Tilt the webcam down so that I can see your desk area.
If you do not have Zoom video and audio running during the exam, you
will recieve no credit for the final exam.
You may use a separate laptop or even cell phone to run Zoom.
As you take the exam, every few minutes or so, take a quick glance at the
Zoom Chat window for any text messages. There may be general announcements,
like the password for the exam or any corrections to typos on the exam, or
there could be a message specifically to an individual. For example, you
might get a message saying your webcam or microphone is not working and
the final exam won't count if it is not fixed. Or maybe it'll say please
tilt your webcam down. Such messages are obviously important, so please be
sure to be frequently checking the Zoom chat window, say, once every two
or three questions you answer.
This is a cumulative final, but emphasizes the third helf of the course.
This exam covers all material presented in class and all homework reading
assignments.
This includes
guest lectures and any websites assigned as homework reading.
The exam will emphasize material covered since the second midterm exam.
In particular, be sure to know the topics of
+ the search for life on Mars
+ the Jovian moons: Europa, Titan, and Enceladus
+ extrasolar planets (exoplanets); the Kepler Mission
+ the Drake Equation and SETI; and the Rare Earth hypothesis.
The exam is cumlative, but emphasis will be on Chapters 7-12.
Exam will consist of 50 multiple choice
questions, with 5 possible choices for answers (a,b,c,d,e). There are no
"trick" questions - the best answer is the right answer.
You will have a full two hours to take the exam, so you should not
be pressed for time.
Be sure to review the following:
- basic properties of the planets
- the concepts and motivation for the big bang theory
- size and scale of the solar system
- the size of the galaxy and the distances to stars
- stellar evolution
- the origin of the elements: Big Bang and stellar nucleosynthesis
- basic biochemisty of life on Earth: carbon (organic) based life, DNA,
proteins, genetic code, handedness (chirality/enantiomers),
etc.
- the importance of water
- the 3 domains of life on Earth: archaea, bacteria, eukarya
- extremophiles
- evolution and extinction
- the importance of comets, asteroids, and NEOs for biology
- Mars and its importance for astrobiology
- Europa and the icy Jovian moons
- the Cassini/Huygens mission; discoveries about Titan and Enceladus
- extrasolar planets: discovery methods, properties, etc.
- the latest results of NASA's Kepler Mission
- SETI & the Drake equation
- the Rare Earth Hypothesis
- the Doppler effect; radial velocities
- the Principle of Occam's razor and the scientific method
You do NOT need to study/review the following:
- any of Fred Hoyle's many accomplishments, other than his role in
panspermia and cosmology
- specific sizes in km or masses in kg of any of the planets, but do know
that Jupiter is roughly ~300 times more massive than Earth, and Venus is
a little less massive than Earth, and Mars is ~1/10 the mass of
Earth.
- details of COBE or the WMAP missions (but know what they are and what
they did)
- anything about Mercury, Uranus, Neptune, or the dwarf planet Pluto
- anything about the dwarf planet Ceres except that it is a now considered
an asteroid belt object
- how to calculate distances via parallax (but know what parallax is!)
- the specific details of the 3 Viking biology experiments (but do know
the results!)
- anything related to modes of space travel (e.g. chemical or non-chemical
rocket propulsion); because time is short, we are omitting much of Ch 13.
- DO NOT memorize the genetic code!! But of course, know how to read
it and what it means.
- Anything about radio galaxies, elliptical galaxies, giant molecular
clouds, white dwarfs, neutron stars, pulsars, black holes or gamma ray
bursters. (You do need to know a bit about types of stars, star formation,
stellar evolution, supernova, and cosmic rays though.)
- Any moons except for the four Galilean satellites, Titan and
Enceladus, and the concept of cryovocanism on the icy moons in general.
- 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 classes of
extremophiles; you should know the different types (classes) of
extremophiles e.g. thermophilic, halophilic, etc..
- You do not need to memorize any molecular structures. For example, you
will not be asked to know the molecular difference between adenine and
guanine. But you do need to know what these molecules do!
- You do not need to know the location of the elements in the periodic
table, or their properties, with the exception of "CHONPS".
Textbook: skip the following sections:
Telescopes and interferometry
Optical or any non-radio SETI
Human evolution
Dyson spheres
(skip all the "Movie Madness" sections)
Anything to do with the encephalization quotient
Galactic colonization
ET and the human condition
Also, you will not need to know any physical constants except the speed of
light,
Wien's constant, and Hubble's constant.
You will not need to know exactly how many meters are in a parsec
or how many AU in a light year or that sort of thing. But you do need
to know the metric system (how many nm in a km, etc.), conversion of units,
and the definitions of an AU, arcsecond, megaparsec, etc..
You may be asked to do a few very simple math-related problems.
You will be asked questions that test your understanding of
certain laws, even if you are not asked to calculate anything using that
law. For example, while you will not be asked, "At what wavelength does
the peak of blackbody radiation from Venus' surface occur at (given that
Venus' surface temperature is 750 K)?", you may be asked "What does Wien's
law tell us about the relation between temperature and wavelength?".
You won't be asked, "How old is the Universe if
Ho = 49 km/s per Mpc?", but you may be asked "How do you
determine the age of the Universe from Hubble's constant?"
The class lectures (not just the on-line notes) should be your
primary source of information.
The material covered in class are the most important items to know
for the final exam. This includes any guest lectures, and material covered
in class that are not in the notes. This is usually (but not always)
about more up-to-date discoveries and results.
Look over the midterm exams to help you prepare for the final exam.
Some "be sure to know these" hints:
- What is the Fermi paradox?
- What does "temperature" really measure?
- What is "endosymbiosis"?
- What is a chloroplast? What is a mitochondrion? What is a ribosome?
- Why is Mars such an interesting place for astrobiology?
- What have the Mars Rover missions discovered?
- How are extrasolar planets discovered?
- What is the Drake Equation?
- What are the arguments supporting the Rare Earth hypothesis?
- 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 can you use spectroscopy for?
- Given a star's surface temperature, at what wavelength is the light
from a star the brightest?
- What makes a hypothesis a scientific hypothesis and not
just an idea?
- Know the uses of the following: Doppler effect, Wien's law, Hubble's
law
- Approximately what is age of the Earth? How do we know?
- "We are all made of star-stuff." What does this mean?
- What are three largest divisions (domains) of life on Earth?
- What role do supernovae play in the origin, evolution and development of
life?
- What are the main discoveries of the Cassini/Huygens mission?
- What are the main discoveries of the Kepler mission?
- What is SETI and why has it concentrated on radio frequencies?
- How big is the solar system? How far to the nearest stars? How big is
the galaxy?
- What is a NEO?
- What is the K/T boundary?
- What makes Europa interesting for astrobiology?
- What makes Titan interesting for astrobiology?
- What do the letters "ATP" stand for?
- What do the letters "CHONPS" stand for?
- What do the letters "NASA" stand for?
- What do the letters "ESA" stand for?
- What do the letters "DNA" stand for?
- What do the letters "JPL" stand for?
- What do the letters "UFO" stand for?
- What is Occam's Razor?
- What is the difference between a hypothesis and a theory?
- 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 "water hole"?
- Why do SETI investigations mostly use radio electromagnetic
radiation?
- What is the difference between infrared, ultraviolet, radio and
X-rays?
- What is TRAPPIST-1 ?
- What it the core premise of the Rare Earth hypothesis?
- What are the factors in the Drake equation?
- What is the difference in meaning between the words "galaxy", "solar
system", and "universe"?
- What is a carbonaceous chondrite?
- What does "terraforming" mean?
- What is panspermia?
- What is the Kuiper Belt?
- What is Ceres?
- What is Elizabeth Loftus' thesis? What has she discovered? Why is
this relevant to UFOs?
- What was Project Mogul?
- Why does a planet's position in the galaxy make a difference to the
ability for life to exist on that planet?
- What causes the greenhouse effect?
- What was the main theme of the documentary "Your Inner Fish"?.
- Who was Alfred Wegener?
- Who is Bill Borucki?
- Who is Jill Tarter?
- Who is Seth Shostak?
- Who is Carl Woese?
- What did the father and son Alvarez team discover?
- Why are astrobiologists suddenly so interested in Enceladus?
- Why doesn't deep-sea water boil if its temperature is 400 degrees?
- 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 is the solar wind?
- Why couldn't terrestrial planets exist very soon after the big bang?
- What is "CHONPS" and why is it important?
- What are the 3 major pieces of evidence for ancient life on Earth?
- What are monomers and polymers?
- Why are amino acids important?
- What is DNA and RNA? How do these work?
- 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 "chicxulub"?
- What is "51 Pegasus" (51 Peg)?
- If someone says, "But it's only a theory...", why does that make no
sense to a scientist, if interpreted strictly?
- What kind of information can you find on SpaceWeather.com?
- What kind of information can you find on the Cassini-Huygens website?
- What kind of information can you find on NASA's Mars
Exploration Program website?
- Who is Seth Shostak?
- What is Proxima Centauri b? Why is it important
- Why do we say that all terrestrial life is biochemically the same?
- Why is it more likely that we will find procaryotes rather than
eucaryotes when we finally expore Europa or Enceladus or Mars?
- What is "apophis" and why is it important?
- What is an enantiomer? (hint: it is related to "chirality")
- What is Lake Vostok? Why is it important?
- What are "plate tectonics"?
- What are "hydrothermal vents"?
- What role have meteors+comets played in the origin and evolution of life on
Earth?
- What is cryovolcanism? Where do we find this?
- What are biomarkers / biosignatures?
- What are two excellent biomarker gases?
- Why do exoplanets have names like "HD 209458 b"?
* How can we detect biosignatures/biomarkers?
* What is the difference between an extremophile and an organism that can
tolerate extreme conditions?
* What is a "circumbinary planet"?
* What are the differenences between a Jovian and a terrestrial planet?
* What is a "hot jupiter"?
* What are the properties of hot jupiter extrasolar planets?
* Why is it harder to find terrestrial planets than Jovian planets?
* Have we discovered any terrestrial planets yet?
* Have we discovered any planets in the habitable zone yet?
* What are the different ways to discover exoplanets?
* What exactly does the phrase "Earth-like planet" mean?
* What is the Kepler Mission?
* How does the Kepler Mission achieve its goals?
* What are circumbinary planets?
* What is so interesting about the planets in the TRAPPIST-1 system?
* What does the "Google Mars" website contain?
- What does "the handedness of terrestrial life" mean?
A suggestion: Review the lecture notes on "What is Astrobiology?"
from very early in the semester. It is a good way to know what the main
topics of the course are. This particular set of notes does not expire -
you can still download it. Also take a look at the "Big Picture" review
notes.
And of course, if you have been using the "Teach Yourself" part of the
class website, those are very helpful tools for learning the material.
And finally, some practice questions from old exams:
The star TRAPPIST-1 has a surface temperature of only 2560 K. What kind of
star is this? Hint: The surface temperature of the Sun is about 5800 K.
A) an A-type star
B) a B-type star
C) an O-type star
D) a G-type star
E) an M-type star
The phrase "One bone, two bones, many bones, then fingers (or toes)"
is related to:
A) the documentary "Your Inner Fish"
B) Earl Towson's guest lecture on Mars
C) Darwin's initial Tree of Life
D) the evolution of mammals
E) all life on Earth being carbon-based
Which of the following is TRUE?
A) gamma rays from F-type stars can cause mutations in panspermia cells
B) guanine is a polymer chain of the sugar glucose
C) canals on Mars are good evidence that Mars was once had seas of water
D) Enceladus cannot harbor life because it is beyond the Sun's habitable zone
E) a UFO sighting does NOT imply the existance of extraterrestrial life
Which of the following is FALSE (NOT TRUE)?
A) life on Earth uses ATP to store and utilize small amounts of energy
B) the search for extraterrestrial life in the solar system is essentially a
search for liquid water
C) a valid scientific hypothesis must potentially be falsifiable by
observations
D) although very hardy, not even extremophiles can live above
100 degrees C (= 212 F)
E) with the exception of some hydrogen, our bodies are composed
of "star stuff"
Which of the following is FALSE (NOT TRUE):
A) "stellar evolution" is a scientific theory to explain how and why stars age
B) "natural selection" is a scientific theory to explain biological evolution
C) evolution is a non-random sequence of steady improvements as a result of a
species trying to better adapt to its environment
D) the most uncertain factor in the Drake Equation is the lifetime of a
civilization
E) ribosome are where proteins are created.
Who is Jill Tarter, and why was she chosen by Time Magazine in 2004 as
one the world's 100 most influential and powerful people?
A) she is the Principle Investigators of the Kepler Mission
B) she solved the Fermi paradox
C) she discovered the first extrasolar planet
D) she is the director and scientific leader of the SETI Institute
E) she was the first to decipher the genetic code
Which of the following is a place on Earth that may possess conditions
similar to those on Jupiter's satellite Europa?
A) the Atacama desert in Chile
B) the Allen Hills in Antarctica
C) Roswell, New Mexico
D) Shark Bay, Australia
E) Lake Vostok
Which is most directly related to the expanding universe and the big bang
theory?
A) Shostak's Slide Rule
B) Wien's law
C) Woese's law
D) Hubble's law
E) Wegner's law
Nitrogen is the 7th element in the periodic table. How many protons are
there in the nucleus of a nitrogen-14 isotope?
A) 7
B) 8
C) 9
D) 14
E) 21
Which of the following moons feels the strongest tidal force, thus is the most
geologically active?
A) Callisto
B) Europa
C) Enceladus
D) Titan
E) Io
Which of the following is FALSE?
A) the Earth's core is hot due to thermonuclear fusion of hydrogen into helium
B) the Earth's core is hot due to heat given off by radioactive decay
C) heat from the Earth's core creates convective motion that drives plate tectonics
D) some of the energy responsible for the Earth's hot core comes from tidal forces
E) some of the heat in the Earth's core is left over from gravitational
accretion during the Earth's formation
A WWWeb site reports the discovery of "a 4.27811529 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
recycling of the crust by plate tectonics (subduction).
D) choices B) and C)
E) choices A), B), and C)
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.
An SDSU student uses the Mt. Laguna Observatory to measure the
spectrum of a star and finds an absorption line at 657.1 nm. In the
laboratory, this spectral line is normally at 656.3 nm. What can the
student deduce about this star?
A) It must be much hotter than the Sun.
B) It must be much cooler than the Sun.
C) It must be moving toward the Earth.
D) It must be moving away from the Earth.
E) It must have an planet orbiting around it.
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
How long would it take astronauts to travel from the Earth to the nearest
star if the astronauts could travel near the speed of light?
A) 1 light year
B) 4-5 years
C) a few thousands years
D) 25,000 years
E) 100,000 years
The K-T global mass extinction event (now called the K-Pg event) was
probably caused by
A) supernova
B) extended ice age
C) the Sun entering the white dwarf stage
D) impact with an asteroid
E) contamination by microbes on ALH84001
To date, most extrasolar planets have been discovered via
A) Hubble's law
B) astrometry
C) the transit method
D) gravitational microlensing
E) the Doppler effect
The planet called "51 Peg" is an important extrasolar planet because
A) it was the first exoplanet discovered
B) it is the most massive planet ever found
C) it is the most Earth-like planet found
D) it was the first transiting planet discovered, so we know its
radius
E) it was the first extrasolar planet discovered to be in a
habitable zone
The planet called "Proxima b" is an important extrasolar planet because
A) it is the most Earth-like planet found
B) it is the smallest planet ever found
C) Proxima Centauri is the nearest star to the Solar system
D) it was the first transiting planet discovered, so we know its mass
E) Proxima b the first extrasolar planet discovered to be in a
habitable zone
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
For the following question, the name of a person and the work they are related
to are paired together. Choose the pair in which the person is **NOT**
logically related to the topic that follows after the arrow.
A) Jill Tarter <-----> the search for extraterrestrial radio transmissions
B) Carl Sagan <-----> "Extraordinary claims require extraordinary evidence"
D) Frank Drake <-----> the lifetime of an advanced civilization
C) Giordano Bruno <-----> the Rare Earth hypothesis
E) Bill Borucki <-----> NASA's Kepler Mission
For the following question, the name of a person and the work they are related
to are paired together. Choose the pair in which the person is *NOT* logically
related to the topic that follows after the arrow.
A) Seth Shostak <--> SETI
B) Carl Woes <--> the domain archaea
D) Frank Drake <--> number of intelligent civilizations in Milky Way
C) Stanley Miller <--> the Chixculub impact and the end of the dinosaurs
E) Lynn Margulis <--> endosymbiosis and the origin of eukaryotes
The name of NASA's current Mars rover, and the one to be launched during
the summer of 2020 are:
A) Voyager 1 and Voyager 2
B) Pathfinder and Sojourner
C) Cassini and Huygens
D) Spirit and Opportunity
E) Curiosity and Perseverance
F) Viking 1 and Viking 2
For homework, you examined the Saturn Moons Explorer website
about Enceladus. What information was mentioned on the website?
A) the hot spot near the south pole has erupting geysers
B) the source of the energy to melt the ice comes from tidal forces from
Titan
C) the existance of amino acids in the geyser plumes
D) the existance of nucleotides on the rocky surface
E) the cold icy interior allow for "cryo-stasis" (locking microbes in
ice for millions of years)
Which of the following is NOT on NASA's Mars Exploration Program
website?
A) links to Current Missions including the Mars Science Laboratory
B) a link to "Where are the Spacecraft?"
C) a link called "Be a Martian"
D) a link called "Send a Postcard to Spirit"
E) a link to a re-analysis of the Viking Mission data
On the Google Mars website homepage, which of the following is
shown?
A) many links to information on the internet about Mars missions
B) many links to science fiction movies about Mars and Martians
C) a mosaic of images from the gamma ray portion of the spectrum
D) a shaded relief map color-coded by altitude
E) links to Mars.com, the homepage of the chocolate and conglomerate,
with company information, operations, careers, products and trademarks.
Good Luck!
If you enjoyed this course, tell your friends about it.
I have taught this course over 20 times now, and as always, I have
enjoyed teaching bright, enthusiastic, hard-working, and inquisitive
students like yourselves.
Because I will be busy working on the NASA's TESS Mission and
other research,
I will be teaching this course only in the Spring semesters.
Good luck on this and any other final exams.
Cheers,
Prof. Welsh.