Unit Test

24 July 2022
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question
90 % of marine organisms and 70% of land organisms died off due to environmental and/or climate changes during the Paleozoic Era.
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True
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Index fossils are used to determine the _________ of the rock.
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a. age
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Actual age refers to the relative age, while comparison age refers to absolute age.
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False
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The breakup of Pangea caused climate changes that caused organisms to adapt or die off, this occured during the Paleozoic era.
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False
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Fossil age can determine organism changes related to the time scale.
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True
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What are the types of unconformities that can occur in rock layers?
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d. all of the above... angular/ disconformity/nonconformity
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Describe how a fossil would form through mineral replacement.
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Fossils form through the process of mineral replacement beginning when an organism dies and is buried. Groundwater seeps around the organism, and the minerals in the water gradually replace the minerals in the hard parts of the organism. Over time these minerals turn into a stone replica of an organism.
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Which of these are most likely homologous structures? bat wing dragonfly wing Tyrannosaurus arm
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bat wing and Tyrannosaurus arm
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Explain what is meant by correlating rock layers.
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if you saw a rock layer, then traveled some distance away and saw the same rock layer, you could assume that they were once together as one. correlating rock layers means that at some point, when a big rock layer was joined together as one, over time, agents of physical destruction and erosion caused them to separate
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When did the fault in Figure 13-1 occur?
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Between B and A
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Fossils provide scientists with evidence that allows them to hypothesize how living organisms have evolved over time. Tiktaalik roseae was a unique organism that has been shown to be 375 million years old. It has been nicknamed the "fishapod" because it is believed to be a common ancestor of both fish and tetrapods, the first four-legged animals. How would a scientist study the relationship between the Tiktaalik roseae and modern fish and tetrapods?
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create a diagram that hypothesizes ancestry
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Describe how the dominant life forms changed during the Mesozoic and Cenozoic Eras.
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After the breakup of Pangaea early in the Mesozoic Era, reptiles were the dominant form of land animal. The first small dinosaurs appeared during the Triassic Period. Later, during the Jurassic and Cretaceous Periods larger dinosaur species evolved. For most of the Mesozoic Era, gymnosperms were the dominant plant form. After the mass extinction that marked the end of the Mesozoic Era, many life forms, including the dinosaurs, disappeared. Mammals became more prevalent, and angiosperms spread throughout the Cenozoic Era.
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What is a nonconformity?
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Gap in the rock layer that is due to erosion or periods without any deposition.
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Order the units or geologic time from the longest to the shortest: Era, Period, Epoch, Eon.
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Eon, Era, Period, Epoch
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In rock layers, jellyfish fossils are found lower than trilobite fossils, and trilobite fossils are found lower than ammonite fossils. What can be determined from this information?
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Jellyfish existed before trilobites and ammonites.
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Complex organisms with gills and lungs were major life forms that existed in the_____________.
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Paleozoic era
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Mineral replacement, carbon film and molds are a few examples of
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fossil preservation
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Shifts in the rock layer locations cannot account for gaps in the rock record
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False
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Which best describes the fossil record?
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The fossil record is inaccurate because scientists are not able to date fossils.
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Eons, eras, periods, and epochs, are all examples of ____________time.
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geologic
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______________ can be used to date fossils in rocks to give an approximate age.
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radiocarbon dating
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Mammals evolved into larger organisms and began subdividing into various species in the _____________.
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Cenozoic era
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Scientists notice structural similarities between fossils of a land animal and an aquatic organism. They know the similarities are not a result of the two organisms having to adapt to similar environments. What can they attribute the structural similarities to?
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common ancestry
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Why are the Miller-Urey experiments essential to the theory of evolution?
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They showed how organic molecules could be made from Earth's early atmosphere.
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Thylacosmilus is a marsupial, and Smilodon is a mammal. Thylacosmilus and Smilodon both have saber teeth, but they do not share an ancestor that had saber teeth. What are saber teeth for these organisms?
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analogous structures
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Isotopes of the same element will have a different number of neutrons, but the same number of protons.
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True
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____ on the geologic time scale are marked by major, striking, and worldwide changes in the type of fossils present.
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Eras
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Changes in the trilobite exoskeleton can be attributed to ____.
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both a and b...changing environments/competition for survival
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An unconformity is a ______ of rock.
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missing layer
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Determining the order of events and the relative age of rocks by examining the position of rocks in a sequence is called ____.
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relative dating
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The Precambrian time period is segmented into very few parts because:
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the fossil record is scarce
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gaps in rock layers that develop when agents of erosion remove existing rock layers
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uncomformities
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To be a useful index fossil, a species must have been rare.
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False
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Siblings have similar traits because they inherit those traits from a common ancestor. How is this similar to some evidence for evolution?
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Similarities can be seen among related organisms, which shows common ancestry.
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Wisdom teeth are the third and final set of human molars that come in during the late teens or early twenties. In some cases, these teeth come in without problems, but they often have to be removed due to misalignment in the jaw, as shown below. Removal of the teeth does not cause any long-term complications in regard to eating.
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vestigial
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Scientists used major changes in life forms in the fossil record to form the geologic time scale.
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True
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Fossils most often form when a dead organism is buried in sediments.
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true
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Rock layers are correlated if they both contain the same ____.
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fossils
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Flowering plants are ______.
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angiosperms
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Little is known about much of Earth's early history because ____.
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all the above