Q&A Hero

Q: Which of the following is modern descendant of the Gymnosperm? A) pine trees B) tulips C) turkeys D) crocodiles E) sharks

Q: Which era is sometimes called the "age of dinosaurs"? A) Pleistocene B) Cenozoic C) Cretaceous D) Mesozoic E) none of these

Q: What group of animals were the first to leave the ocean to become the first amphibians? A) horn-beaked Cephalopods B) trilobites C) lobe-finned fish D) salamanders

Q: The largest mass extinction in the Phanerozoic occurred in the ________. A) Jurassic B) Devonian C) Permian D) Cambrian E) Miocene

Q: During the Cambrian, Trilobites developed a flexible exoskeleton which allowed them to ________. A) avoid being eaten by other creatures B) climb trees and find food C) burrow in soft sediment to find food D) eat smaller life forms by crushing them in their jaws E) sink to the bottom of shallow ponds to find food

Q: The first fully land-based animals were ________. A) reptiles B) amphibians C) eukaryotes D) stromatolites E) cephalopods

Q: An important evolutionary step for reptiles was ________. A) the development of shell-covered eggs B) the growth of scales from armor plating C) lungs that could hold air D) the formation of a true spine

Q: A major obstacle the first land plants had to overcome was ________. A) finding food on land where there were no organic compounds B) staying upright despite gravity and wind on land C) their lack of mobility because they needed water access D) the large number of plant eating organisms on land E) eliminating waste materials in the atmosphere

Q: Which type of bacteria thrive in environments that lack free oxygen? A) aerobic B) placental C) anaerobic D) foraminifera E) photosynthetic

Q: A distinctive characteristic of prokaryotes is ________. A) their thick cell walls that separate the DNA from the rest of the cell B) their lack of a separation between the DNA and the rest of the cell C) their oxygen based metabolism D) their methane based metabolism E) their ability to produce sugars

Q: Which of the following is not a hypothesis for how life began? A) Methane and hydrogen sulfide from deep-sea hydrothermal vents and hot springs like those at Yellowstone National Park provided the necessary materials. B) Asteroids and comets brought amino acids to Earth. C) Outgassing and related volcanic materials brought proto amino acids to the surface of the earth. D) Methane and ammonia in the early atmosphere combined with the help of lightning or ultraviolet light to produce the first amino acids.

Q: Scientists have found evidence that life existed at least 3.5 billion years ago ________. A) in northern Siberia B) on the Gulf Coast C) throughout North and South America D) in Kenya E) in several locations around the world

Q: The most common Precambrian fossils are ________, layered mounds of calcium carbonate. A) prokaryotes B) chert C) trilobites D) eukaryotes E) stromatolites

Q: What organic compounds are essential for DNA and RNA to form? A) ammonia and methane B) hydrogen sulfide C) carbon dioxide D) oxygen E) amino acids

Q: A major site of sediment deposition during the Cenozoic was ________. A) the Gulf of Mexico B) the Rocky Mountains C) the western coast of the U.S. D) the central U.S. E) central Texas

Q: The Laramide Orogeny at the end of the Mesozoic produced ________. A) the Appalachian Mountains in the eastern U.S. B) the Ural Mountains in Russia C) the Alps in Europe D) the Rocky Mountains in the western U.S. E) the Himalayan Mountains in Asia

Q: The North American Cordillera formed as a result of ________. A) the subduction of the Atlantic basin beneath North America B) the subduction of the Pacific basin beneath North America C) the evolution of the San Andreas Fault zone D) the growth of the Appalachian Mountains

Q: At the start of the Triassic, most of the continents were above sea level, and sediments from that time are often red because ________. A) they contain extensive deposits of iron ore B) they are a major source of uranium and red quartz C) they include iron oxides D) the dry climate baked clays to form hornfels E) there are extensive dune fields

Q: By the close of the Paleozoic, all the continents had fused into the single super continent of ________. A) Laurasia B) Pangaea C) Appalachia D) Gondwanaland E) Europa

Q: During the early Paleozoic era, South America, Africa, Australia, Antarctica, India, and perhaps China comprised the vast southern continent of ________. A) Europe B) Laurasia C) Gondwanaland D) Antindia E) Pangaea

Q: During the ________ era, the westward-moving North American plate began to override the Pacific plate, eventually causing the tectonic activity that ultimately formed the mountains of western North America. A) Precambrian B) Paleozoic C) Mesozoic D) Cenozoic E) none of the above

Q: A major economic deposit associated with the Cretaceous period is ________. A) gold B) uranium C) sand D) coal E) platinum

Q: At the start of the Paleozoic, North America ________. A) had abundant life B) had no plants or animals C) did not exist D) was a large number of small fragments that had not yet collided E) was mountainous and dry

Q: The beginning of the Phanerozoic is marked by the ________. A) evolution of land plants and animals B) development of hard body parts, such as shells and bones C) abundant life forms compared to earlier times D) formation of large land masses E) existence of a modern atmosphere

Q: During the late Paleozoic, the present-day North America, Europe, western Asia, Siberia, and perhaps China formed the northern continent of ________. A) Gondwanaland B) Laurasia C) Greenland D) Africa E) none of the above

Q: The supercontinent of Pangaea began to break up during the ________ era. A) Precambrian B) Paleozoic C) Mesozoic D) Cenozoic

Q: The Appalachian Mountains formed as a result of ________. A) the break-up of Pangaea B) the collision of North America and Africa C) the collision of North America and Europe D) the collision of Greenland and Norway E) the initial formation of Pangaea

Q: Evidence that Gondwana formed near the South Pole include ________. A) paleomagnetic data from the region B) identification of cold temperature mammals C) penguin fossils D) evidence of continental glaciation

Q: The slight eastward slope of the Great Plains was created during the Cenozoic by ________. A) uplift of the western U.S. due to the formation of the Rocky Mountains B) uplift of the western U.S. due to volcanic activity C) deposition of sediments shed from the eroding Rocky Mountains D) uplift of the expanding Basin and Range Province E) tilting of the U.S. because of sediment deposited on the trailing edge of the plate

Q: Most ________ rocks are devoid of fossils, which hinders correlation of rocks. A) Precambrian B) Paleozoic C) Mesozoic D) Cenozoic E) Mesozoic and Cenozoic

Q: Sea level rise can be caused by ________. A) the formation of supercontinents B) rapid erosion from continents that increase the sediment load in the oceans C) fast seafloor spreading D) slow seafloor spreading E) slow erosion from continents that increase the size of land masses and displace water

Q: Antarctica became glaciated because ________. A) it moved to a position over the south pole B) ocean circulation changed with the northward movement of South America C) ocean circulation changed with the southward movement of South America D) global climate changed with the formation of the Himalayan Mountains E) a meteorite impact changed the earth's tilt axis

Q: In Rodinia, a well-documented Precambrian supercontinent, ________. A) there is no evidence of North America B) North America was the last collision in the formation of the supercontinent C) North America and South America made up one continuous fragment D) North America was located near the center of the supercontinent E) the Rocky Mountains were located to the south of the North American craton

Q: The North America craton formed as a result of ________. A) collision of older crustal fragments composed of island arcs and other fragments B) the collision of two continents to form a supercontinent C) the break-up of a large supercontinent D) a huge volcanic eruption E) the metamorphism of oceanic crust

Q: Preserved rocks in North America are generally less than ________. A) 20 km wide B) 10 km thick C) 50 km long D) 3.5 billion years old E) 2.7 g/cm3 in density

Q: Continental crust is formed by ________. A) melting and differentiation of oceanic crust at subduction zones B) partial melting of mantle rocks C) plumes of hot igneous material that rise from the core-mantle boundary to form hot spots D) the original planetary accretion that also led to the formation of the earth's other layers E) recycling of material in giant lava lakes in the early earth history

Q: One significant difference between oceanic and continental crust in terms of the long term evolution of the earth's surface is that ________. A) oceanic crust is less dense than continental crust B) oceanic crust preserves a history of ancient deformation better than continental crust C) continental crust is harder to subduct than oceanic crust D) continental crust is more uniform in composition than oceanic crust E) oceanic crust contains more radioactive elements that contribute to the heating of the earth.

Q: Zircons found in continental rocks give evidence that continental crust was forming as long ago as ________. A) 4.4 billion years ago B) 1.9 billion years ago C) 564 million years ago D) 70 million years ago E) 10,000 years ago

Q: One important reason we do not know much about the geologic history of the Precambrian is that ________. A) rocks did not exist during much of that time B) the climate was so harsh that erosion removed most of the rocks that formed during the Precambrian. C) radioactivity was not measurable during the Precambrian D) we have not yet been able to establish the half-lives for radioactive elements that existed in the Precambrian E) there are very few fossils preserved in Precambrian rocks

Q: Banded Iron Formations are interbedded iron oxides and chert that formed on the sea floor between 3.5 and 2 billion years ago because ________. A) iron and chert were very abundant in the early earth B) iron was using the oxygen produced by bacteria and chert was a common ocean deposit C) chert was being deposited by bacteria and iron was a common ocean deposit D) photosynthesis had not yet started to generate oxygen so iron and chert were the deposited on the sea floor E) outgassing produced both chert and iron oxide in roughly equal amounts and the oceans became saturated with them

Q: The modern oceans are a major repository for the greenhouse gas ________, which some organisms utilize to make their shells. A) SiO2 B) Ammonia C) Limestone D) CO2 E) Iron oxide

Q: In the early history of the earth, the solid surface of the earth weathered more rapidly than now because ________. A) the early rain was very acidic B) the rocks at the surface were weak because there was little oxygen available C) the atmosphere contained large amounts of corrosive methane D) there was little topography so shallow water washed across the surface often E) there were numerous earthquakes and volcanoes breaking up the surface

Q: The large size of insects and amphibians during the Pennsylvanian period has been suggested to be due to ________. A) a lack of predators for early land forms B) an excess of sunlight and water during that time C) an excess of oxygen during that time D) a decrease in methane in the atmosphere during that time E) the emergence of a super continent that allowed greater areas for animals to evolve

Q: The Great Oxygen Event marks the time, approximately 2.5 billion years ago, when ________. A) there was enough oxygen in the atmosphere to support a major burst of life on Earth B) there was a massive volcanic eruption that lead to a very rapid increase in oxygen levels on Earth C) there was a cataclysmic weather event that absorbed most of the oxygen in the atmosphere and locked it into iron deposits in the oceans D) there was significant oxygen in the atmosphere E) photosynthesis was clearly established and producing oxygen.

Q: The first bacteria probably used ________ instead of water as a source of hydrogen. A) H2SO4 B) HCl C) H2S D) OH-1 E) Fe3O4.OH

Q: The waste gas released by plants as they synthesize food sugars from carbon dioxide and water is ________. A) oxygen B) methane C) nitrogen D) carbon dioxide

Q: Earth's primitive atmosphere evolved from gases ________. A) produced by radioactive decay B) collected from the nebula C) escaping from water D) from the Sun E) expelled from within the earth

Q: The process in which plants use light energy to synthesize food sugars from carbon dioxide is called ________. A) photosynthesis B) hydration C) oxidation D) fusion E) none of these

Q: The major source of free oxygen in the atmosphere is from ________. A) molten rock B) water C) green plants D) silicate minerals E) glaciers

Q: Much of the early hydrogen and helium escaped the earth's atmosphere into space because ________. A) The earth's gravity was weak B) The earth's gravity was strong C) Solar winds were strong D) Solar winds were weak E) All of the above

Q: Which one of the following represents the greatest expanse of geological time? A) Mesozoic B) Cenozoic C) Precambrian D) Paleozoic

Q: Earth's core, mantle, and crust formed during the ________. A) Archaean B) Proterozoic C) Paleozoic D) Hadean E) Tertiary

Q: Early Earth was hot because ________. A) there was still heat from the original big bang B) gravitational collapse generates heat C) a combination of collisions and radioactive decay produced heat D) the Sun was much larger and heated the early planet E) the moon's formation from an giant impact produced heat

Q: As they formed, due to their high temperatures and comparatively weak gravitational fields, which planets were unable to retain appreciable amounts of hydrogen, helium, and ammonia? A) Jupiter and Neptune B) Mercury and Earth C) Uranus and Pluto D) Jupiter and Uranus E) Neptune and Uranus

Q: Which of the following was an important factor in determining the different parts of the solar system where the small rocky planets formed versus where the light, gaseous planets formed? A) density B) viscosity C) temperature D) gravity E) velocity

Q: The ________ means "the Sun in the making." A) solar disk B) presun C) nebular Sun D) sol E) protosun

Q: As the solar system began forming, the first materials to condense into small particles were ________ and nickel. A) oxygen B) silicon C) nitrogen D) carbon E) none of these

Q: Planetesimals, asteroid-size objects, form during the early history of the solar nebula due to ________. A) collisions of particles of ice, metal, and rocky material rotating about the protosun B) vortices in the rotating disc associated with the protosun C) the formation of comets in the outer parts of the solar nebula D) the break-up of the solar nebula as it cools and contracts

Q: The heaviest element produced by nuclear fusion in a young star is ________. A) nickel B) oxygen C) helium D) iron E) sodium

Q: The first elements to form after "Big Bang" were ________. A) oxygen and hydrogen B) oxygen and iron C) hydrogen and iron D) helium and oxygen E) helium and hydrogen

Q: The earth formed approximately ________ years ago. A) 5,000 B) 11,000,000 C) 4,600,000,000 D) 13,700,000,000 E) 33,200,000,000,000

Q: The Goldilocks scenario suggests that ________. A) we are very fortunate that the meteorites that have bombarded the earth over time were not too large or too small B) we are very fortunate to be in the right place in the universe and to have had the right condition to develop and sustain life C) we are very fortunate that dinosaurs were destroyed but left us an inhabitable planet D) we are very fortunate to be in a solar system where life can develop and be sustained

Q: What would have happened to the earth if the Sun were significantly larger than it is? A) Our atmosphere would consist mainly of carbon dioxide. B) Our atmosphere would consist mainly of nitrogen. C) Liquid water and the water cycle would not exist. D) Our Sun would have burned out after a few hundred million years so life would not evolve.

Q: What would have happened to the earth if it were 10% farther from the Sun? A) Our atmosphere would consist mainly of carbon dioxide. B) Our atmosphere would consist mainly of nitrogen. C) Liquid water and the water cycle would not exist. D) Our Sun would have burned out after a few hundred million years so life would not evolve.

Q: What would have happened to the earth if it were 10% closer to the sun? A) Our atmosphere would consist mainly of carbon dioxide. B) Our atmosphere would consist mainly of nitrogen. C) Liquid water and the water cycle would not exist. D) Our sun would have burned out after a few hundred million years so life would not evolve.

Q: Why is the molten metallic outer core and the magnetic field important to life on Earth? A) If we did not have the molten core and the magnetic field, the earth would not have plate tectonics and would be covered entirely by water. B) If we did not have the molten core and the magnetic field, the atmosphere would be very different with either too much ammonia and methane or too little oxygen and water. C) If we did not have the molten core and the magnetic field, we would be bombarded by cosmic rays that would strip away our atmosphere. D) If we did not have the molten core and the magnetic field, we would be bombarded by meteorites and we would not be able to hold the moon in orbit.

Q: Why is it important that we have a rigid lithosphere overlying a weak asthenosphere? A) If we did not have the rigid lithosphere and weak asthenosphere, the earth would not have plate tectonics and would be covered entirely by water. B) If we did not have the rigid lithosphere and weak asthenosphere, the atmosphere would be very different with either too much ammonia and methane or too little oxygen and water. C) If we did not have the rigid lithosphere and weak asthenosphere, we would be bombarded by cosmic rays that would strip away our atmosphere. D) If we did not have the rigid lithosphere and weak asthenosphere, we would be bombarded by meteorites and we would not be able to hold the moon in orbit.

Q: Why is the mass of the earth important to maintain life as we know it? A) If we had more or less mass, the earth would not have plate tectonics and would be covered entirely by water. B) If it had more or less mass, the atmosphere would be very different with either too much ammonia and methane or too little oxygen and water. C) If the earth's mass were significantly different, we would be bombarded by cosmic rays that would strip away our atmosphere. D) If the earth's mass were greater, we would be bombarded by meteorites and if it were smaller, we would not be able to hold the moon in orbit.

Q: What kind of unconformity is produced when tilted, older strata are eroded and buried by younger strata?

Q: What general term denotes a buried, erosional surface where rock layers are missing?

Q: What term denotes blocks of older rock enclosed in a body of younger igneous rock?

Q: The phrase, "The present is the key to the past," refers to the doctrine of ________.

Q: One method to obtain the absolute age of a sedimentary rock is to obtain a radiometric date on an interbedded volcanic rock.

Q: Most sedimentary rocks are readily dated by radiometric methods.

Q: All of geologic time prior to the beginning of the Paleozoic era is termed the Phanerozoic eon.

Q: The term Paleozoic describes the era of ancient life forms.

Q: The term Mesozoic refers to life forms intermediate in complexity between early and much later, more modern-looking life forms.

Q: The geologic time scale was devised before numerical dating using radioactivity was invented.

Q: After two half-lives, there is no longer any of the original radioactive material remaining.

Q: When a beta particle is emitted, the mass number of the isotope remains unchanged.