1. Evolution Unit Exam on Friday
Describe the structure of the cell membrane. What type of biomolecules are present and what are their functions?
Evolution Unit Exam on Friday

2. Plan for Today Evolution Quiz Early Earth Video and Questions
Miller and Urey Reading
Early Earth Timelines

3. How did life on earth begin?
Answer the video question worksheet

4. Miller and Urey Reading
Read and annotate the article and answer the reading analysis questions

5. Miller and Urey Miller and Urey mimicked conditions on early earth
Demonstrated that amino acids and other molecules important for life could have formed
Used hydrogen gas, water, methane, and ammonia

6. Early Earth Earth formed about 4.6 billion years ago
The first life on earth was a simple, prokaryotic cell (3.8 billion years ago)
Over time, natural selection selected for more complex prokaryotic cells (2.6 billion years ago)
Eventually, photosynthesis (autotrophic) bacteria form
This filled the atmosphere with oxygen
Different selection pressures life today
Humans have existed for about 200,000 years

7. Evidence for Early Life on Earth
Carbon Dating of Rocks
Iron banding patterns suggesting presence of oxygen
Relative dating of fossils

9. Example Timeline

10. Life on Earth Timeline
Create a poster that shows the timeline of early life on earth to today
Attempt to make it to scale (as close as possible)
Include drawings and other items to help you remember the relative order
Include at least main events
Write in bold/emphasize:
1. First prokaryotic cells
2. Rise of oxygen in the atmosphere
3. First land plants
4. First aquatic animal
5. First mammals
6. Homo sapiens