What are the four steps to forming a petrified fossil?
sediment, layers, movement, erosion
100
How are petrified fossils formed?
Petrified fossils form when minerals replace all or part of an organism.
100
What does "petrified" mean?
turning into stone
100
Igneous Rocks and Metamorphic Rocks?
Igneous rocks are minerals that are fused together after being melted, and metamorphic rock are minerals that reform and then fuse together because of heat, pressure, and time.
100
What is a hypothesis?
Making an educated guess about the answer to your problem
200
Describe what happens during the "sediment" step.
An animal is buried by sediment, such as volcanic ash or silt, shortly after it dies. Its bones are protected from rotting by the layer of sediment.
200
How is a mold formed?
A mold forms when hard parts of an organism are buried in sediment, such as sand, silt, or clay.
200
What does "preserved" mean?
kept from rotting
200
The words preserved and petrified?
Preserved means kept from rotting, while petrified means turning into stone.
200
Where do plants get their energy from?
the sun.
300
Describe what happens during the "layers" step.
More sediment layers accumulate above the animal’s remains, and minerals, such as silica (a compound of silicon and oxygen), slowly replace the calcium phosphate in ?the bones.
300
How is a cast formed?
Water with dissolved minerals and sediment fills the mold’s empty spaces.
Minerals and sediment that are left in the mold make a cast.
300
What is the definition of a fossil?
the preserved remains of a once-living organism.
300
Trace fossils and mold fossils?
Mold fossils must be buried under sediment, while trace fossils form from a footprint.
300
What is a herbivore?
An organism that eats plants only.
400
What happens during the "movement" step?
Movement of tectonic plates, or giant rock slabs that make up Earth’s surface, lifts up the sediments and pushes the fossil closer to the surface
400
How are trace fossils formed?
An animal makes a footprint when it steps in sand or mud.
Over time the footprint is buried in layers of sediment. Then, the sediment becomes solid rock.
400
What is sediment? You can give examples.
mineral or organic matter deposited by water, air, or ice. examples: clay, silt, volcanic ash
400
Amber and tar?
Amber comes from the sticky resin from trees. Tar is a material made up of debris such as coal.
400
What is an omnivore?
An organism that eats both plants and animals.
500
What happens during the "erosion" step?
Erosion from rain, rivers, and wind wears away the remaining rock layers. Eventually, erosion or people digging for fossils will expose the preserved remains.
500
How can we get a carbon film on a fossil?
When an organism dies and is buried in sediment, the materials that make up the organism break down.
Eventually, only carbon remains.
500
What is erosion?
the process by which the surface of the earth is worn away by the action of water, glaciers, winds, waves, etc
500
Preserved Remains and petrified fossils?
Preserved remains are when some organisms get preserved in or close to their original states. Petrifed fossils Petrified fossils form when minerals replace all or part of an organism.
500
What is photosynthesis?
a process by which green plants and other organisms turn carbon dioxide and water into carbohydrates and oxygen, using light energy trapped by chlorophyll