Chapter 12 Section 3

1. Chapter 12 Section 3 Life Invaded the Land Grade 10 Biology Spring 2011

2. Ojectives • Relate the development of ozone to the adaptation of life to the land • Identify the first multicellular organisms to live on land • Name the first animals to live on land • List the first vertebrates to leave the oceans

3. The Ozone Layer • ______ provides life giving light and dangerous ___ light • Early in Earth’s history, life formed in the _____, where early organisms were ___________ from _____________

4. Formation of Ozone Layer • About 2.5 million years ago, photosynthesis by __________ began adding _________ to Earth’s ____________ • As oxygen began to reach upper atmosphere, the sun’s rays caused some of molecules of ________, 02, to chemically react and form molecules of __________, 03 • In the upper atmosphere, _______ ______ the ___ radiation of the sun • After millions of years, enough ______ had accumulated to make the Earth a safe place to live

5. Plants and Fungi on Land • First _____________ organisms to live on land may have been ______ living together with __________________ • Each possessed a quality needed by the other

6. Plants and Fungi on Land • Plants: likely evolved from _________ • Could carry out ___________________ • In photosynthesis: plants use energy from ______ to make ___________ • Plants cannot harvest needed _________ from bare rock • Fungi cannot make nutrients from _________ but can absorb minerals from bare rock

7. Plants and Fungi on Land • ____________: symbiotic associations between fungi and the roots of plants • Fungus provides minerals to plant, plant provides nutrients to fungus • _____________: relationship between two species in which both species benefit • Plants and fungi began living together on the surface of the land about 430 million years ago

8. Arthropods • _____________: first animals to successfully invade land from sea • Hard outer ______, segmented body, and paired, jointed limbs • Ex. Lobsters, crabs, insects, spiders • _______ have become the most plentiful and diverse group of animals in Earth’s history • Insects have the ability to ____ • Partnership between _____ and _______

9. Vertebrates • ___________: animal with a backbone • Ex. Humans • Fishes • First vertebrates were small, ________ fishes that evolved in the oceans about 530 million years ago • ____ enable fish to bite and chew their food instead of sucking up their food • Became most _______ animals in sea

10. Vertebrates • _____________: first vertebrates to inhabit the land • Smooth skinned, four legged animals • Ex. ___________________________________ • Had moist breathing sacs –_________- which allowed the animals to absorb __________ from air • _______ of amphibians are thought to have derived from bones of fish fins

11. Vertebrates • _________: evolved from amphibian ancestors about 340 million years ago • Snakes, lizards, turtles, and crocodiles • Reptiles are better suited to _______ than amphibians because reptiles water tight skin slows the loss of __________ • Have watertight eggs, can lay eggs on ___________

12. Mammals and Birds • _________: evolved from feathered dinosaurs during or after the Jurassic period • _________: evolved from therapsids (reptiles with complex teeth and legs positioned beneath their body) gave rise to mammals about the same time dinosaurs evolved

13. Mammals and Birds • All of the dinosaurs except _______ of birds became _______ • Smaller reptiles, mammals, and birds __________ • There were many __________ available to the surviving animals, the world’s climate was no longer largely _____ • Reptile’s _________ in dry climates were not so important • Birds and mammals then became the ________ vertebrates on land

14. Continental Drift • Both extinctions and continental drift played important roles in evolution • _______________: movement of Earth’s land masses over Earth’s surface through geologic time • Resulted in present day position of continents