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75 Cards in this Set

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Evolution:
Proc.ess by which modern organisms have _______from ancient organisms
descended/ evolved
The organisms change ________over time
gradually
Darwin sailed to many continents and islands on a ship called the ______________ and collected a variety of organisms
HMS Beagle
Today scientists estimate that over ____% of the species that once live on earth are extinct
99
______was the first one to use the word fitness
Darwin
Fitness is the combination of __________ ________ and _________ that help an organism survive and ___________ in their environment
physical traits,
behaviors,
reproduce
How did all these organisms develop the structures that give them their fitness?
Common descent
Darwin tried to answer the wonder of common descent in his book called ________________________________________________________
The origin of species by means of natural selection
WHAT IS URANIUM 238'S HALF LIFE? and WHAT DOES IT DECAY INTO?
half life- 4.5 billion
Decays into- led 206
Any inherited ________ that increses an organisms _______ for survival is ADAPTATION.
characteristics,
fitness
Giraffes have long necks to reach leaves that are too high for other animals to reach, therefore they are better able to survive and pass their _______ on to their offspring.
genes
James _________ and Charles _______ were geologists who believed the earth was constantly changing.
Hutton,
Lyell
Other scientists started to study rocks and ______ to determine the age of the earth.
fossils
Preserved remains of __________ ___________ are FOSSILS

Examples:
insects, dinosaurs, _________, ________, gases, mammals, etc.
ancient organisms,
plants, animals
A record of the history of life determined by the layers of rock is the _____________________________________________
Geologic Time Scale
The oldest rocks are in the _________ layers - the youngest rocks are in the ________ layers.
lower,
upper/higher
Technique used to determine the age of fossils by comparing them with other fossils. ____________________. This does not produce exact age of the fossil.
Relative Dating
Unstable element that decays into a more stable or non-radioactive element at a known rate... ________________________________
Example: C-14 decays into ____________
RADIOACTIVE ELEMENT,
nitrogen 14 (n14)
Length of time required for half of the radioactive atoms in a sample to decay. _______________________
half-life
This means that after one half-life,________ of the radioactive atoms in a sample have decayed.
half
Each radioactive element has a ______________ half-life
known/recorded
Absolute dating is also know as ___________ _________.
RADIOACTIVE dating
Method of measuring radioactive decay of a radioactive material to determine how long ago an event occurred or an organism lived.
ABSOLUTE DATING/(AKA) RADIOACTIVE DATING
Using radioactive dating and examination of other geological processes such as weathering of rocks, scientists have determined the earth is about ______ billion years old.
4.6
What is the half-life of carbon?
5,770 years
Largest interval of time in a geologic time scale
era
interval in a geologic time scale that is composed of epochs
period
interval of time in a geologic time scale (subdivisions of periods)
epoch
How old is the earth?
4.5 or 4.6 billion years old
HOW DO FOSSILS FORM?
-organisms may become..
-trapped in snow or ______
-insects trapped in sap of trees called ______
-trapped in peat bogs, quicksand, or ______ pits
-the material that surrounded the organism prevented it from decaying and allowed it to be preserved
ICE,
AMBER,
TAR
large rock broken down into small particles of sand, silt, or clay due to heat, cold, or rain which are compressed under water
Sedimentary Rock
Most fossils are found in ________________ rock
sedimentary
The study of fossils
Paleontology
FOSSIL RECORD:
-History of the __________ preserved in rocks.
-Could be a plant, animal or even a footprint
-Fossils show us how organisms change over time
Fossils
WHAT IS AMBER?
______________ that has become rock.
tree sap
Earliest ages of development of an organism.
EMBRYO
If embryos look similar, they are probably related and have similar _________ and a common __________.
genes,
ancestor
Organ that has no useful ____________.
EX:
-Boa and python have leg bones.
-Tail bone and __________ in humans.
-__________that moves ears in humans.
Function,
appendix,
cartilage
SIMILARITIES IN CHEMICAL COMPOUNDS
examples are:
______,
______,
______,
Proteins such as cytochrome c
DNA,
RNA,
ATP
THE PROCESS BY WHICH MODERN ORGANISMS HAVE DESCENDED FROM ANCIENT ORGANISMS
EVOLUTION
the person responsible for what we know about EVOLUTION
charles darwin
in 1831, Darwin sets out on the ______ _______ to collect animal and plant specimens from different countries and continents. He spent a good deal of time in the Galapogos Islands- where he found a great diversity of species
HMS Beagle
The ability to survive and reproduce in your environment
Fitness
in 1859, darwin publishes a book that shows his findings on his voyage. the name of the book was __________________________________________________________
The origin of species by means of natural selection
What is Darwin's principle of common descent?
Common descent says that all species, over long periods of time have evolved from a shared or common ancestor.
According to Darwin, fitness arises through ___________
adaption
What do successful adaptations do for a living organism?
Enable organisms to become better suited to their enviroment, better able to survive and reproduce.
Provide an example of an adaptation for a living organism
long neck of giraffe- allows them to eat off trees that other grazing animals cannot- this makes them better able to survive and reproduce- and pass their genes onto their offspring
Much of our evidence about the age of the earth is found in __________
rocks
Many scientists believe the earth to be approximately
4.6 billion years
What did James Hutton propose in 1788?
That rocks, mountains, and valleys had been changed by rain, heat, cold, volcanoes, etc.
While examining the earth's rocks, geologists began to make discoveries. they found _________ inside stone that showed preserved remains of ancient organisms.
SOME RESEMBLED MODERN DAY ORGANISMS, SOME DO NOT
fossils
The Geologic Time Scale: A clock in the Rocks
What does the position of a rock's layers tell you about the fossils found in those layers?
-The position of the layers of rocks relative to each other determines their age.
-Lower layers are deposited earlier, so they are older.
-Fossils found in lower layers lived before fossils found in upper layers.
A technique used by scientists to determine the age of fossils relative to other fossils in different layers of rock.
RELATIVE DATING
Radioactive dating is also known as what?
Absolute dating
Radioactive dating: rocks are made up of many types of elements. some of these elements are _________, which means they give off radiation
radioactive
As radioactive elements ______, or break down, scientists can measure it at a very steady rate.
Decay
Scientists measure this rate of decay in a unit called _______-________.
half-life
The unit of time required for half the radioactive atoms in a sample to decay
Half- life
FACT CARD
Example of half-life:
Uranium-238 takes 4.5 billion years to break down HALF of its atoms. if scientists find a fossil that has 1/2 of the Uranium atoms decayed (broken down), they know that fossil is from 4.5 billion years ago.
Radioactive Dating and other studies have allowed scientists to divide the 4.6 billion years to life into large units called ___________.
Eras are divided into ________.
Periods are divided into __________.
Eras,
Periods,
Epochs
Provide two examples that describes how fossils can form?
1. insects and other small animals were occasionally trapped in the sticky tree sap that eventually hardened into amber
2. in cold places, animals sometimes fell into crevasses in ice or became trapped in snow fields.
Most fossils are found in _____________ rock. These are formed when exposure to heat, rain, and cold breaks down existing rocks into small pieces of clay, sand & silt
Sedimentary
These small particles are carried by _______ & rivers into ________ and _______.
streams & rivers into lakes and seas
FACT CARD
Organisms that die in the water will fall to the bottom and become embedded in the forming layers. Eventually, pressure from the lower layers compresses the sediments and turns them into sold rock!
Does the fossil record tell us the whole story about once-living organisms? Why or why not?
No, because not all things fossilize. The fossil record is not as complete as we would like it to be.
If you were a paleontologist and you found shark teeth in a Fossil found in Arizona, what would that indicate to you?
indicating that the desert was once covered by ancient seas.
FACT CARD
Similarities in vertebrate embryos show that similar genes are at work. Genes that control an animal's basic body plan (head, tail, limb position) are similar.

These similarities show ancestral relationships which provide further evidence of evolution.
Similar in bone structure, but different in function
HOMOLOGOUS STRUCTURES
How does the discovery of homologous structures support evolution?
Scientists see that it can't be a coincidence that all organisms are very similar. Homologys like chemical similarities prove that organisms evolved from a common ancestor. (Similar embryos, bones structure, etc.) ( chemical compound structure )
Organs that are so reduced in size or function that they are merely vestiges (traces) of similar organs in other species.
VESTIGAL ORGANS
FACT CARD
Examples of Vestigal Organs:
humans- tailbone at the base of our spine (dont need) ear cartilage, etc.
Chemical Compound Similarities:
All organisms even share similarities in chemical compounds. All living organisms are made up of ______ & ________ and use ________ as an energy carrier.
DNA & RNA and use ATP
FACT CARD
the structural and biochemical similarities among living organisms are best explained by Darwin's conclusion:
LIVING ORGANISMS EVOLVED THROUGH GRADUAL MODIFICATION OF EARLIER FORMS, OR
DESCENT FROM A COMMON ANCESTOR!
IS LAURA AWESOME?
YES!