Astriobiology HNRS 228 Mid-Term Exam - 1 Name: __________________ HNRS 228 – Fall 2011 Mid-Term Examination Answers 1. You have 100 grams of a radioactive element with a half-life of 4 years. How many grams of the original element remain after 12 years. A 100 grams B 50 grams C 25 grams *D 12.5 grams E 6.25 grams 2. Which of the following is closest to the number of kilometers in a light year? A 10,000 kilometers B 10,000,000 kilometers C 10,000,000,000 kilometers *D 10,000,000,000,000 kilometers E This is a trick question, a light year is NOT a unit of distance, but time. 3. Which of the following is (are) larger than an Astronomical Unit? A The distance to the nearest star B The distance from the Earth to the Moon C The distance from the Mars to the Sun *D Only A and C above are larger than an Astronomical Unit. E A, B and C are all larger than an Astronomical Unit. 4. The center of the Milky Way galaxy A could not be located because the Milky Way galaxy is always moving. *B is located in the direction of the constellation Sagittarius.Astriobiology HNRS 228 Mid-Term Exam - 2 C is not at any one location. D is the one point in the universe everything is moving away from. E was destroyed by the original big bang explosion. 5. Which of the following is the best conclusion from Miller-Urey experiment? A Life could not evolve on Earth, rather it came from somewhere else. *B A primordial soup plus energy can produce complex organic molecules. C Life must have originated in deep ocean vents D The primordial atmosphere had the same constituents as the current atmosphere E Life can be produced in a test tube. 6. What happens when a solar nebula collapses? A The temperature in the nebula increases. B The pressure in the nebula increases. C The density in the nebula decreases. *D Only A and B are true about the characteristics in a nebula collapsing to produce a star. E A, B, and C are true about the characteristics in a nebula collapsing to produce a star. 7. Using the proper phase diagram from those provided, what phase would carbon dioxide be at a temperature of -78.5oC and an atmospheric pressure equivalent to one half (1/2) of that of Earth's at sea level?Astriobiology HNRS 228 Mid-Term Exam - 3 A The carbon dioxide would exist as a liquid *B The carbon dioxide would exist as a gas C The carbon dioxide would exist as a solid D The carbon dioxide could be in any phase, solid, liquid or gas E The carbon dioxide could be either in a gas or solid phase 8. Earth possesses few visible craters and the moon possesses many. This is because A Earth formed later than the moon and, therefore hasn't encountered as many meteoroids B The Moon doesn't have an atmosphere that could burn up meteorites before impacting C Erosion and plate tectonics have slowly removed evidence of past cratering on Earth D All of the above are true *E Only B and C above are true 9. Which is the best description of scientific reasoning? A Scientific reasoning is the derivation of conclusions from observations.Astriobiology HNRS 228 Mid-Term Exam - 4 B Scientific reasoning is the application of critical thinking applied to natural observations. *C Scientific reasoning is the application of critical thinking applied to natural observations keeping in mind fundamental natural laws. D Scientific reasoning is just another term for mathematical logic. E Scientific reasoning is just another term for critical thinking. 10. Extinction events in geological history are characterized by several common features. Which of the following is true about major extinction events? A No recovery of species number and diversity. *B Large number of taxa or species lost. C Geological time period for extinction event measured in more than a few hundred million years. D All of the above are true about extinction events in geological history. E None of the above 11. Which of the following particles are not made up of quarks? A Protons B Neutrons C Electrons D Neutrinos *E Both C and D above are not made of quarks. 12. At which layer of the Earth (using the diagram below) would you find liquefied iron?Astriobiology HNRS 228 Mid-Term Exam - 5 A B *C D E None of the above 13. In which layer of the Earth (using the same diagram) do you find amorphous (putty like) rock? A *B C D E None of the above layers contain liquefied iron. 14. Of the following, which is NOT necessary in setting a definition of life based upon attributes of living organisms? A Metabolism. B Reproduction. C A medium for metabolism. D A mechanism for the transfer of energy. *E All of the above are necessary in a definition of life. 15. Which of the following chemical molecules is not a requirement for metabolism in anaerobic micro-organisms? A Water *B Molecular Oxygen (O2)Astriobiology HNRS 228 Mid-Term Exam - 6 C Carbohydrates D Proteins E Carbon 16. Which of the following chemical elements is found in our atmosphere? *A Nitrogen B Carbon dioxide C Water D Sulfur dioxide E Carbon monoxide 17. Rocks that are formed from the cooled magma or lava from a volcano are called A sedimentary rocks. B metamorphic rocks. C gemstones. D minerals. *E igneous rocks. 18. Microbes that inhabit unusually “hot” environments are known as A acidophiles. B halophiles. *C thermophiles. D alkalinophiles. E arachnophiles. 19. Rocks that are a changing combination of the other two kinds of rocks and are changed due to pressures, physical and chemical are called A sedimentary rocks. *B metamorphic rocks. C gemstones. D minerals. E igneous rocks.Astriobiology HNRS 228 Mid-Term Exam - 7 20. Copernicus was the very first person to suggest that the Sun is the center of the solar system. A True *B False 21. Radiometric dating is a type of A relative dating. *B absolute dating. C Einstein dating. D concentric dating. E dendrochronological dating. 22. The different layers of the sedimentary rock provide a type of *A relative dating. B absolute dating. C Einstein dating. D concentric dating. E dendrochronological dating. 23. The group of organisms that have cellular structure characterized by a lack of nuclei and multiple organelles are called A anaerobes. B aerobes. *C prokaryotes. D eukaryotes. E extremophiles. 24. Water dissociates to produce ions that are either positively charged (H+) or negatively charged (OH-). The resulting concentration of H+ and OH- in