1. Chapter 10, section 4 Welcome to Earth! LT: I will demonstrate my knowledge of fossils, rock layers, and ice cores. http://www.youtube.com/watch?v=E4yirtvUurA&feature=related

2. Agree Disagree 1._______ ________ 2._______ ________ 3._______ ________ 5._______ ________ 4._______ ________ Scientists estimate the Earth’s age to be around 4.6 billion years old. Some of the water on Earth came from comets in space. Most of the earliest fossils are organisms that lived on land. According to the fossil record, bacteria were some of the first organisms on Earth. Fossils show that the continents have always been in the same location on Earth.

3. I. Formation of Earth A. Scientists use radioactive dating to estimate the Earth’s age at 4.6 billion years

6. B. Gravity caused rocks, dust and frozen gas to come together

7. II. Earth’s Surface A. Water vapor from volcanoes is added to the Earth’s surface 1. Comets from space add additional water and other gas

10. B. Continental Drift – slow movement of continents over Earth’s surface. 1. Evidence = scientists use fossils and rock layers to match the coasts of continents http://www.youtube.com/watch?v=QDqskltCixA

12. http://www.youtube.com/watch?v=NYbTNFN3NBo&feature=related

13. Untold tragedies of Continental Drift.

14. III. Precambrian Time A. Early fossils are single celled organisms and bacteria 1. Most lived in the ocean and did photosynthesis

16. Fossils of early multi-cellular ocean organisms

17. B. Bacteria and phytoplankton in water created oxygen gas 1. Today, over half the Earth’s oxygen is still made in the ocean!!

18. Agree Disagree 1._______ ________ 2._______ ________ 3._______ ________ 5._______ ________ 4._______ ________ Scientists estimate the Earth’s age to be around 4.6 billion years old. Some of the water on Earth came from comets in space. Most of the earliest fossils are organisms that lived on land. According to the fossil record, bacteria were some of the first organisms on Earth. Fossils show that the continents have always been in the same location on Earth.