Exercise
Mold and Cast Fossils
Explore how mold and cast fossils form when organisms decay and leave impressions in sedimentary rock.
Questions
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MultiChoice
What is created when mineral-rich sediment fills a mold fossil and hardens?
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MultiChoice
An impression left in sedimentary rock by the outer surface of a buried shell is called a:
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MultiChoice
How does a mold fossil differ from a cast fossil?
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MultiChoice
What step must occur before a natural cast fossil can form?
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MultiChoice
If a seashell dissolves completely after being buried in mud, what is left in the rock?
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MultiChoice
Which everyday activity is most similar to how a cast fossil forms?
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MultiChoice
What substance typically fills an ancient mold to produce a natural cast?
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MultiChoice
Which part of a seashell determines the details seen on a mold fossil?
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MultiChoice
Why are molds and casts valuable to paleontologists studying ancient sea life?
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MultiChoice
In which type of rock are mold fossils most commonly discovered?
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MultiChoice
What happens if sediment fills a mold cavity before water dissolves the surrounding rock?
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MultiChoice
Can a single buried seashell form both a mold and a cast over time?