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8 Geology Revision
8 Geology Revision

... a. Erosion is the movement of rocks and/or weathering products by water, wind, ice or gravity down the slope and also by living organisms. b. What is the difference between weathering and erosion? ________________________________________________________ ______________________________________________ ...
Chapter 21 - Bemidji State University
Chapter 21 - Bemidji State University

... Geology - The study of planet Earth - its composition, structure and history. I. Minerals - A naturally occurring, crystalline, inorganic substance (element or compound) that possesses a fairly definite chemical composition and a distinctive set of physical properties. Oxygen and silicone make up 75 ...
Chapter - ISpatula
Chapter - ISpatula

... been easy to overlook certain slender, 3-cm-long creatures gliding through the water: Myllokunmingia fengjiaoa (Figure 34.1). Although lacking armor and appendages, this ancient species was closely related to one of the most successful groups of animals ever to swim, walk, slither, or fly: the verteb ...
Directed Reading
Directed Reading

... 28. What is weight, and what unit is used to measure it? ...
Animal kingdom
Animal kingdom

... • Phylum Porifera (e.g.sycon,Euspongia,Spongilla) 1.Commonly known as sponges. 2.Generally marine,asymmetrical & have cellular level of organisation. 3.Water enters through minute pores in the body wall called ostia into a central cavity spongocoel & goes out through osculum.Choanocytes or collar c ...
Preview as PDF - Pearson Higher Education
Preview as PDF - Pearson Higher Education

... In The Origin of Species, Darwin predicted the existence of fossils of transitional forms linking very different groups of organisms. For example, he hypothesized that whales evolved from land-dwelling mammals. If this hypothesis was correct, then fossils should show a series of changes in a lineage ...
Evidence for Continental Drift
Evidence for Continental Drift

... Use the terms in the vocabulary box to fill in the blanks. Each term may be used only once. 1. Alfred Wegener proposed that, millions of years ago, all the continents were joined as a 2. The name given to this giant land mass is 3. Wegener compared ...
34-The Origin and Evolution of Vertebrates
34-The Origin and Evolution of Vertebrates

... been easy to overlook certain slender, 3-cm-long creatures gliding through the water: Myllokunmingia fengjiaoa (Figure 34.1). Although lacking armor and appendages, this ancient species was closely related to one of the most successful groups of animals ever to swim, walk, slither, or fly: the verte ...
What is a Rock?
What is a Rock?

... Schist: dominated by platy or needle-like minerals that form shiny layers Gneiss: under pressure the minerals in granite recrystallize to form bands of light and dark minerals Marble: Limestone recrystallizes into marble – a denser and more crystalline form of calcite Quartzite: Sandstone changes in ...
Earth`s Systems and Cycles - Independent School District 196
Earth`s Systems and Cycles - Independent School District 196

... How are humans affecting the carbon cycle? What environmental problems are caused by excess carbon dioxide in the atmosphere? Key terms: Photosynthesis, combustion, respiration, deforestation, decomposition (pp. 14 -15) 6. Trace the path of nitrogen through the nitrogen cycle. Why is nitrogen an ess ...
restless continents text
restless continents text

... When Wegener put forth his hypothesis of continental drift, many scientists would not accept his hypothesis. From the calculated strength of the rocks, it did not seem possible for the crust to move in this way. During Wegener’s life, no one knew the answer. It wasn’t until many years later that evi ...
X. PHYLOGENY, cont
X. PHYLOGENY, cont

...  Derived Traits – new traits that evolved after ancestral trait  Synapomorphies – shared among a group of organisms; viewed as evidence for common ancestry of group. EX: vertebral column of vertebrates  May see evolutionary reversals – a character may revert from a derived state back to an ancest ...
Continental Drift and Plate Tectonics
Continental Drift and Plate Tectonics

... Paleomagnetic evidence • Orientation of the magnetized crystals at the time of mineral formation • Earth reverses its magnetic north at variable intervals ...
Ch 28 answers all Sr 28-1 #1: 3 arthropod features: a) tough
Ch 28 answers all Sr 28-1 #1: 3 arthropod features: a) tough

... tick (parasites) chelicerae : needle-like structures pierce the skin of host, may have large teeth to keep a firm hold on the host SR 28-3 Crustaceans p. 620 #1) cephalothorax: part of the exoskeleton that has the head and thorax segments fused together: it is covered by a tough shell called the car ...
Geo Time Vocab
Geo Time Vocab

... There will be a vocabulary test over these words after the project is due! ...
C1b Foundation 1
C1b Foundation 1

... In the 1950s two scientists, Miller and Urey, investigated the origin of life on Earth. Miller and Urey used the gases that they believed were in the Earth’s early atmosphere and used water to represent the oceans. The gases they used were methane (CH4), ammonia (NH3) and hydrogen (H2). A continuous ...
What is Photosynthesis?
What is Photosynthesis?

...  Leaves and chloroplasts are adaptations for photosynthesis in plants – The outer surface of both epidermal layers is covered by the cuticle, a transparent, waxy, waterproof covering that reduces the evaporation of water from the leaf – Leaves obtain CO2 for photosynthesis from the air through pore ...
2014 - UO Blogs - University of Oregon
2014 - UO Blogs - University of Oregon

... to  pursue  fundamental  questions  such  as  where  did  life  (including  us)  come   from,  how  are  different  life  forms  related  to  each  other  and  what  can  a  deep   understanding  of  one  life  form  tell  us  about ...
Slide 1
Slide 1

... a) For 200 million years, the proportions of different gases in the atmosphere have been much the same as they are today: ■ about four-fifths (80%) nitrogen ■ about one-fifth (20%) oxygen ■ small proportions of various other gases, including carbon dioxide, water vapour and noble gases. g) Most of t ...
Activity 5
Activity 5

... According to Wegener, about 200 millions years ago, a huge supercontinent called Pangea (Greek for all land) broke into separate continents that moved apart.Wegener claimed that compression at the leading edge of the moving continent led to the formation of mountains.Wegener’s hypothesis allowed him ...
Metamorphic Rocks
Metamorphic Rocks

... to rocks in Earth’s interior • produced by increased heat, pressure, or the action of hot, reactive fluids • old minerals, unstable under new conditions, recrystallize into stable ones ...
Hall of Planet Earth Educator`s Guide
Hall of Planet Earth Educator`s Guide

... formed. Along with all the other planets, Earth was created from clouds of dust orbiting our infant Sun. Molten at first, the planet differentiated into a molten iron core and a silicate outer layer — within a few tens of millions of years. Shortly thereafter the Moon formed, possibly from material ...
Chapter 14: Invertebrate Animals
Chapter 14: Invertebrate Animals

... Most animals have either radial symmetry or bilateral symmetry. Animals with body parts arranged in a circle around a central point have radial symmetry. Can you imagine being able to locate food and gather information from all directions? Aquatic animals with radial symmetry, such as jellyfish, sea ...
PowerPoint Presentation - I. Introduction to class
PowerPoint Presentation - I. Introduction to class

... Dimorphism in nonpathogenic fungi may depend on other factors: Carbon dioxide concentration. ...
Helpful and Harmful Microorganisms
Helpful and Harmful Microorganisms

... break down and enrich these composting materials. ...
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Evolutionary history of life



The evolutionary history of life on Earth traces the processes by which living and fossil organisms have evolved since life appeared on the planet, until the present day. Earth formed about 4.5 Ga (billion years ago) and life appeared on its surface within 1 billion years. The similarities between all present-day organisms indicate the presence of a common ancestor from which all known species have diverged through the process of evolution. More than 99 percent of all species, amounting to over five billion species, that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's current species range from 10 million to 14 million, of which about 1.2 million have been documented and over 86 percent have not yet been described.
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