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Mr. Cosby

Team: 7 Burgundy

Voice mail: 303-982-0411 (BUT, please email!)

Current Unit of Study - Geological Events through time:  Unit 8 – Fossils


Students will understand that:

  1. Classification is a process scientists use to organize our understanding of many things in the natural world including living things.
  2. Organisms can be classified following the Linnaean Classification System.
  3. Biological evolution accounts for the unity and diversity of living organisms.
  4. Earth’s geologic history is relevant to understanding the processes that have shaped our planet.
  5. Fossils are the remains of Earth’s past life and give clues to Earth’s past environments.
  6. The vast majority of species to have ever existed on Earth have gone extinct as directed by the forces of Natural Selection.
  7. Layers of sedimentary rock provide evidence used to determine the order of events in geologic time.
  8. Absolute age dating can be obtained with an understanding of radioactive decay.
  9. The vastness of geologic time is difficult to comprehend from a human perspective

Test Date:  April 30th


Resources to Study:


Study Guide


Worksheets and various preentations/notes under Unit 8 folders (classroom Docs)

Notes from class

Returned worksheets

Fossil Websites found on the Student Homepage


Holt Pages:  192-211, 220-234

MSLS Pages: N/A


Unit 7 Vocabulary - Fossils and Earth Science:

Make a Flash Card for each, including drawing that will help act as a hint to help you learn each word!  Example:

 Fossil Record:  The collective knowledge of all of Earth’s past life based on fossils.


Body Fossil:  The fossil remains of an organism’s actual body part.  (Tooth, bone, etc.)


Trace Fossil:  The fossil of markings left by an organism.  (Footprints, burrows, bite marks, etc.)


Biotic:  Living


Abiotic: Non-Living


Classification:  Organizing anything into groups based on similarities.


Taxonomy:  The science of classifying living things.


Species:  Organisms that are genetically similar and capable of reproducing with other members of the same species to produce fertile offspring.


Biodiversity:  A measure of the variety of species in an ecosystem.  (High Biodiversity = many different species.)


Population:  A group of the same species living in an ecosystem.


Classification:  Organizing anything into groups based on similarities.


Taxonomy:  The science of classifying living things.


Extinction:  When a species dies off and is no longer part of Earth’s biodiversity.


Extinct:  A species that no longer exists on Earth.


Sedimentary Rock:  Rock types made from particles of other rocks cemented together.  Fossils are found (mostly) in sedimentary rocks.


Relative Age:  Putting events in order from oldest to youngest.   (Without dates/numbers)


Absolute Age:  Putting dates with events.


Law of Superposition: Basic law of geology stating that new layers must be deposited on top of older layers, so when looking at layered rock sections, the oldest layers are at the bottom, the youngest are at the top.


Radioactive Decay:  The spontaneous change of atoms from one element into another element.


Radioactive:  Elements from the periodic table that can change from one element to another.  Are said to be “unstable” because they can change and give off energy.  The energy released by radioactive atoms inside of the Earth heats the Earth.


Half-life:  The very predictable and steady rate in which many atoms of a radioactive element change into a different element.  Half-life is the amount of time for half of a sample to decay.


Continental Drift: The early hypothesis of Plate Tectonics in which Alfred Wegner suggested the continents may be moving about the surface of Earth.


Plate Tectonics:  The theory that Earth’s crust is broken into huge plates that are being pushed around the surface of Earth because of heat in Earth’s mantle.  Plate Tectonics is responsible for all of Earth’s geological features.


Plate: A large slab of rock making up a section of Earth’s surface.  All of Earth’s surface is covered in continuous plates that fit together like a puzzle.


Oceanic Crust:  Rock that typically makes up ocean floors.  Contains high amounts of iron, which cause oceanic crust to be darker in color and more dense than continental.


Continental Crust: Rocks that typically make up continents.  Contain low amounts of iron, which causes continental crust to be lighter in color and to have much lower densities than oceanic crust.


Divergent:  Plate boundary where the 2 plates are separating from each other.  New crust is made here.


Convergent:  Plate boundary where the 2 plates are colliding.  Old oceanic crust is destroyed here.


Transform:  Plate boundary where the 2 plates are sliding past each other.  Causes earthquakes.


Density: The amount of matter in a given amount of volume.  More dense substances sink in less dense substances.


Subduction: When a more dense plate (oceanic crust) gets pushed into the Mantle when it converges with a less dense plate.  This melts and recycles the crust back into the mantle.


Convection:  The circular flow of material that is caused by hot substances rising while cold substances sink.  Convection allows heat from deep in the Earth to be transferred to the surface as hot rocks rise.  Tectonic Plates move as they are pushed by the circular motion of the mantle convection currents.


Stratigraphic Column:  A drawing that shows layers of sedimentary rock which allows the interpretation of paleoecology.


Pangaea:  A super-continent 300 million years ago when all of Earth’s current continents had come together.


Earthquake:  The shaking of the ground caused by rocks sliding past each other in a fault zone.  (Where 2 plates meet or where a large section of rock is broken in half.)


Natural Selection:  The Process in which organisms that are better adapted to their environments tend to be more likely to survive, and thus have a better chance of passing on those adaptations to offspring.


Mr. Cosby's 7th Grade Science Class

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