Science 8 Unit 1 Flashcards
What is a sedimentary rock and how is it formed?
Sedimentary rock can be formed in several ways.
Some are formed when rocks of any kind are worn away by rain, wind, and other elements.
Through erosion, tiny fragments of the original rock and dissolved minerals are carried away by wind or water to another site.
What is the relative age of rock layers?
Sedimentary rock forms in layers. The oldest layers are at the bottom, and the youngest are at the top. (Not a good answer).
What is the half-life of carbon 14?
The half life of carbon 14 is 5,730 years. Carbon 14 over the years deteriorates. So if an organism has more carbon 14, the organism died more recently than one with less. All organisms have carbon 14. Carbon 13 is more specific.
What is absolute age?
Absolute age is the natural, specific age of an organism.
What is relative age?
Relative age is the approximate age of an organisms based off of other organisms. It’s the same in the case of fossils.
What is a permineralized fossil?
A permineralized fossil happens when an organism’s tissue are replaced by minerals from water. These minerals, then form a three dimensional copy of the original organism.
What is a carbonized fossil?
Carbonized fossil is formed when an organism is quickly buried and flattened by the enormous pressure of sentiments, built up above it most of the organisms, the insides get removed (hydrogen, oxygen, nitrogen), and only the carbon from the organism remains as a thin, black film
What is an amber fossil?
Amber fossil is when amber also known as tree sap encases an organism (usually small) and overtime hardens, preserving the organism perfectly for many, many years.
What are cast and mold fossils?
It is formed after an organism has died and their body left an imprint on the ground, water will then fill this impression and the water minerals will harden to form a cast and mold fossil.
What is a trace fossil?
It’s a record of activity of an organism formed by actions such as footprints.
What is a tar pit fossil?
A tar pit fossil is an area where sticky, thick liquid (asphalt) seeps up the Earth’s surface. The tar covers the organism’s body and dissolved the soft parts, but preserved the hard parts such as a shell.
What are frozen remains?
Frozen remains are when an organism becomes trapped, in some way, dies and then is quickly frozen. As long as the surroundings stay frozen, so with the organism. The freezing preserves genetic material and most of the organism.
What happened first a long time ago?
3.5 billion years ago, everything began with the first tiny living things called microbes. They were the only life on Earth for a long time.
What happened after 3.5 billion years ago?
Half a billion years ago, the first animals started living in warm ocean waters
What happened after half a billion years ago?
460 billion years ago plants and then animals started to appear on land. First came plants because there was no oxygen and the plants needed to make oxygen so that animals could live. Reptilian-like animals first.
