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16 Cards in this Set
- Front
- Back
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According to the theory of evolution how did life start?
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About 3.5 billion years ago atoms combined spontaneously and formed molecules
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What happened next according to the theory of evolution?
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Eventually these molecules lined together in complex groupings
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How did the organisms continue to develop?
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They must have been able to ingest and live on non-organic material. Later they adapted and utilized the sun's energy.When photosynethesis released oxygen into the oceans and the atmosphere, the stage was set for more advanced life forms.
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What were the first cells?
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Prokaryotes (bacteria) which converted energy (respired) without oxegen (anerobic).
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What were the next cells?
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The next cells to develop were cyanobacterium (blue-green algae)and prokaryotes, which were aerobic (created energy with oxygen and used photosynthesis. Advanced eukaryotes developed from these primitive cells.
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What is blue-green algae and what is the significance to the theroy of evolution?
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After the Eukaryotes developed it took 2.7 billion years for algae to develop. When this simple cell appeared 950 million years ago it contained enormous amounts of DNA and animal and plant forms slowly emerged.
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How did the first plants develop?
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Scientists believe plants developed from algae. Algae are often found as green plankton in the ocean or living together with a fungus to form lichen.
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How do Algae reproduce?
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Algae reproduce by cell division and use photosynthesis to make food.
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What developed after algae?
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Scientist believe mosses and ferns developed and that many of today's plants developed from ferns
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How do mosses and ferns reproduce?
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Mosses and ferns use spores to reproduce, but they still use photosynthesis to make food
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Animals developed after plants. Explain the development
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Animals developed into vertebrate (backbone)and intevertebrate (no backbone)species.
Mammals became the dominant vertebrate class, and insects became the dominant invertebrate class. |
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What is natural selection?
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As animals developed they adapted to their environment. Those species that developed best survived. Entire species have vanished from the earth
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What about the dinosaurs?
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Mammals and dinosaurs coexisted for over 100 million years. Dinosaurs were the dominant class. When dinosaurs became extinct 65 million years ago, mammals survived.
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How did the dinosaurs become extinct
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In spite of many years of study no-one knows
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What developed after animals?
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Humans are the primate (upright) family of mammals. Very primitive primates along with other mammals were found on earth before the dinosaurs became extinct.
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What is the correlation between man and apes
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Modern humans demonstrate striking genetic similarities to other members of the primate group particularly African apes.
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