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History of Life on Earth
fossils, early life, evolution
40
Science
8th Grade
02/21/2011

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Cards

Term
How long ago did life on Earth begin?
Definition
About 3.8 billion years (recent evidence suggests closer to 4.4 billion years)
Term
What do we call the remains of organisms preserved in the earth?
Definition
fossils
Term

What is preserved in this fossil type??

[image]

Definition
bones or hard body parts are preserved
Term
What type of fossil is this?[image]
Definition
mineral replacement
Term

What fossil type is this? What might they be preserved in?

[image]

Definition
original remains preserved in amber, sap, or ice
Term
Explain relative dating?
Definition
When the fossils are compared to one another based upon where they are located in the ground.
Term
When we measure the radioactivity given off of a fossil to determine its age, we call this what?
Definition
radioactive or absolute dating
Term
These types of simple celled organisms were probably the first on earth?
Definition

unicellular

[image]

Term
What do we call living things made up of many cells?
Definition
multicellular organisms
Term
The earliest multicellular animals were probably what type of animal?
Definition
tiny seaweed or possibly jellyfish
Term
Until about 500 million years ago, all organisms probably lived where?
Definition
the oceans
Term
The Permian extinction was significant because 90% of all species living where became extinct?
Definition
the ocean
Term
The Cretaceous extinction from 65 million years ago is famous because of the disappearance of what?
Definition
the dinosaurs
Term
The process through which species change over time is called?
Definition

evolution

[image]

Term

Natural Selection was the process brought forth by what individual?

 

Definition
Charles Darwin
Term

This is the definition for what process?

"Members of a species that are best suited to their environment survive and reproduce at a higher rate."

Definition
natural selection
Term
Explain the process of overproduction.
Definition
production of more offspring than can possibly survive in hopes that a few will reach adulthood
Term

What are 3 quality traits that might enable a sea turtle to survive and pass on its genes?

Definition

1. faster on land

2. good swimmer

3. quicker thinker

Term
Natural differences in traits within a species is called?
Definition
variation
Term
Variation (variety) within a species may occur when genetic material changes. This changing of genes is called what?
Definition
mutation
Term
When the changing of genetic material  might give an animal a better chance of surviving. We call this what?
Definition
adaptation
Term
Species do not have a choice in selecting what traits help them to survive. Fill in the blank to properly complete the sentence. "The __________ selects the trait!"
Definition
environment
Term
What do we call the evolution of a new species from an existing species?
Definition
speciation
Term
What is absolutely necessary for speciation to occur?
Definition
isolation. two groups must be isolated and therefore cannot reproduce.
Term
Name 2 types of barriers that might lead to speciation?
Definition
mountains, bodies of water, valleys
Term
What do we call an early form of an organism from which later forms come from (descend)?
Definition
ancestor
Term
What do we call a physical structure that was fully developed and working in an earlier group but is reduced and unused in later species?
Definition
vestigial organ
Term
What do we call several periods in the earth's history when huge numbers of species died off?
Definition
mass extinction
Term
What do we call a segment of DNA that relates to a trait or function?
Definition
gene
Term
A human arm, a dolphin flipper, an elephant leg, and a bird wing all perform differently but have a similar structure. A common ancestor is likely. Is it fossil evidence, biological evidence, or genetic evidence?
Definition
biological
Term

What do we call this structure which contains your DNA and, thus, your Genes?

[image]

Definition
chromosome
Term

 Breeding two champion racehorses to (hopefully) produce a champion offspring is known as what?

a. natural selection   b. artificial selection

c. variation   d. just plain wrong       

Definition
b. artificial selection
Term
What might cause relative dating of fossils  to be incorrect?
Definition
earthquakes, shifting of land, removal or movement of fossils
Term

Complete the following sentence:

 

In radioactive dating, "the older the fossil, the  _______________."

Definition
less radioactivity
Term

Most species today are:

 

a. unicellular

   b. multicellular

Definition
unicellular
Term
These types of organisms are made of specialized cells.
Definition
multicellular
Term
What contains the information all organisms need to grow and maintain themselves?
Definition

DNA

(deoxyribonucleic acid)

Term

Complete the sentence about relative dating:

 

"The deeper the fossil, the ______________."

 

 

Definition
older the fossil
Term
These may replace the remains of an organism to form a fossil.
Definition
minerals
Term
Name 2 characteristics that are a result of a mutation in humans.
Definition
eye color, cancer
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