Lesson #24
100

What are the four geochronological units 

  • Eons
  • Eras
  • Periods
  • Epochs
200

What happened in the Cambrian Explosion

first major diversification of multicellular life

300

What is the RNA world hypothesis 

RNA was the first molecule to catalyze reactions

400

What was the miller-urey experiment

By replicating earth's early atmosphere to see what organic molecules could form

500

What led to the formation of a oxygen rich atmosphere 

photosynthesis