S.S. 2/23 Flashcards
What are Fossils?
Preserved remains of Organisms that lived in the past
Why is studying fossils important?
It teaches us about how life was like in the past and the history of life.
Describe the process of how fossils are formed
Organisms Die → Covered up quickly by sediment → Hardens over Time
Explain why few fossils form.
Biological, Geological, and Organisms Decay and get eaten.
Define and Explain Index Fossils
Index fossils are fossils that are abundant around the world and lived a short period of time
Define the different types of fossils
Cast - Cupcake: Solid 3D Copy of the organism
Mold - Cupcake Mold: Hollow copy of the organism
Carbon Film - Sticker on Paper: Thin outline of a fossil in rock
Petrified - Medusa: turned into stones, minerals replace all of the organism
Trace - Footprint: A Fossil that shows the animal once lived in the exact spot.
Preserved - Scorpion in Candy: When an organism is fully covered by amber, tar, or ice.
Describe the difference between an Intrusion and an Extrusion
Intrusion is inside the earth while extrusions are on the surface. (Intrusion - Internal, Extrusion - External)
Explain the Law of Superposition
The rock layer near the top is younger than the layers under. The layer on the top is the youngest, the layer on the bottom is oldest.
Define and explain the relative age of a rock compared to the absolute value of a rock
Relative Age is when you compare a rock to a rock. Absolute Age is when you use radioactive dating.
Identify the geologic time eras in order from oldest to youngest.
Precambrian Time, Paleozoic Era, Mesozoic Era, Cenozoic Era.
Which organisms evolved in which era?
Single-Cell Organisms in the Precambrian Time
Marine Animals in the Paleozoic Era.
Dinosaurs in the Mesozoic Era
Megafauna (Mammals) in the Cenozoic Era
What Era are we currently in?
Cenozoic Era
What period are we currently in?
Quaternary Period
How old is the earth?
4.6 BILLION years old
