Self-Quiz

Self Test

1. Accretion is the process which: Created the Moon; Created the Earth; Created the Sun; Caused the Sun to grow brighter
2. There is little evidence of the bombardment of the Earth by bolides because: The energy released by the bolides melted the Earth's crust; Radioactivity in the Earth's core caused volcanoes to spew forth lava which covered the earth; Rain water eroded the surface of the Earth; All of the above
3. The atmospheric mixture used in the Miller/Urey experiment contained the molecules: CO₂ and N₂; H₂O, H₂, and O₃; CH₄, NH₃, and H₂; None of the above
4. Why do scientists believe that a reducing atmosphere might have existed when life began?: The Earth was too new to have a big atmosphere; Only a reducing atmosphere allows organic chemistry to occur; Early bolide impacts kept the atmosphere from reducing in size; Oxidizing atmospheres allow organic chemistry to take place only at low temperatures
5. In the Miller/Urey experiment, two percent of the carbon present had formed: Nucleotides; Adenine; Amino acids; Adenosine triphosphate
6. Adenosine triphosphate is an important biological molecule because it: Releases energy when it phosphorylizes; Is one of the four bases for DNA and RNA; Is an enzyme used in DNA replication; All of the above
7. Why do some scientists object to the significance of the Miller/Urey experiment?: The atmosphere was never as reducing as Miller and Urey thought; The energy which was simulated in the experiment was unrealistic; Methane and ammonia dissociate easily in ultra-violet light; All of the above
8. Some scientists believe that deep sea thermal vents are not a likely site for the origin of life because: Organic molecules are unstable at high temperatures; The proposed temperature gradient would be too small to produce a significant amount of organic compounds; The molecules needed to create organic compounds are not present at deep sea thermal vents; a and b
9. Why do some people believe that the meteorite ALH84001 contains ancient bacteria fossils?: It contains carbonate globules; The presence of polycyclic aromatic compounds; They fit the description of bacteria as we know it; a and b
10. SETI is searching the sky in hopes of finding: The presence of organic compounds on distant planets; Radio signals from extraterrestrial organisms; Clues about the creation of our solar system; None of the above
11. Jeffrey Bada proposes that the early Earth's ocean would not completely freeze because: The volume of the ocean is too large; The sun was less luminous than it currently is; The salt concentration in the ocean used to be higher; Hydrothermal vents kept the ocean's temperature warm
12. What is the highly exothermic process by which a heavy nucleus splits into two lighter nuclei called?: Impact frustration; Nuclear fission; Nuclear fusion; Atomic reduction
13. What is the most powerful form of radiation?: Alpha radiation; Beta radiation; Delta radiation; Gamma radiation
14. What did the Murchison meteorite demonstrate?: Meteorites probably caused the extinction of the dinosaurs; The Earth could not have received amino acids from extraterrestrial sources; The Earth could have received amino acids from extraterrestrial sources; None of the above
15. A chiral molecule is one whose mirror image: is superimposable on itself; is non-superimposable on itself; is able to change its conformation; has the same chemical properties

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