Study Guide Flashcards
(21 cards)
What are fossils primarily used for in the study of Earths history?
Understanding past life forms and environments
What era is known as the Age of dinosaurs?
The Mesozoic
Cyanobacteria was significant to Earth’s history because they?
Produced oxygen as a byproduct of photosynthesis
The Silurian period is characterized by?
The evolution of jawed fish and vascular plants
During which epoch did mammals become the dominant land animals and grasses first appeared?
The Oligocene
The Paleozoic Era ended with ?
The largest mass extinction in Earth’s history
How are fossils formed?
Through mineralization of organic remains C weathering
What information can bedrock fossils provide?
Relative age of rock layers D
The Cenozoic Era is often called ?
The age of Mammals
What is a true statement about the fossil record?
It is an incomplete record of past life C
What era did the 1st multicellular organisms appear?
Precambrian
Which type of environment best preserves fossils?
Rapid burial in sediment C desert
The earliest known life forms were?
Single cell organisms
What marked the end of the Mesozoic era?
Massive asteroid impact
What characteristic helps scientists determine the age of fossils?
The layer of the rock it is found in
The Oligocene epoch was characterized by?
Development of the grasslands
What role did Cyanobacteria play in Earths atmosphere?
It produced the first significant oxygen
The fossil record suggests that?
Life forms change over time
What period saw the 1st appearance of land plants?
Silurian
What is the primary way scientists determine absolute dates for fossils?
Radioactive dating
