EARTH SCIENCE
FOSSILS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A plant or animal is covered by sediment.
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Sediments fill a mold and form a cast.
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A plant or animal is eaten.
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Sediments are pressed together and harden.
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Detailed explanation-1: -The first step in becoming a fossil is death. Natural causes, such as predation or disasters could have killed creatures that lived long ago (just as happens today). The second step involves the animal being buried in sediment, preventing it from being eaten by scavengers or decomposed by bacteria.
Detailed explanation-2: -The organism generally must have hard parts such as shell, bone, teeth, or wood tissue; the remains must escape destruction after death; and the remains must be buried rapidly to stop decomposition. This does make the fossil record biased because animals with soft bodies are less likely to form fossils.
Detailed explanation-3: -As rocks at the earth’s surface are broken down, or “weathered, ” the sediment is moved by forces such as water and wind and deposited elsewhere in layers. Over time, these layers build up and solidify, becoming sedimentary rock. Organisms can be preserved as fossils if their bodies are buried within these layers.
Detailed explanation-4: -An animal dies, its skeleton settles on the sea floor and is buried by sediment. The sediment surrounding the skeleton thickens and begins to turn to stone. The skeleton dissolves and a mould is formed. Minerals crystallise inside the mould and a cast is formed. More items