1 / 10

The origins of Life

The origins of Life. Origin of the Solar System. Earth is estimated to be ~4.6 bill. yr old Evidence: Radiometric dating of rocks & meteors Nebula Hypothesis: Nebula: cloud of gas & dust in space Gravity pulled much material together (forming the Sun)

waite
Download Presentation

The origins of Life

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. The origins of Life

  2. Origin of the Solar System • Earth is estimated to be ~4.6 bill. yr old • Evidence: Radiometric dating of rocks & meteors • Nebula Hypothesis: • Nebula: cloud of gas & dust in space • Gravity pulled much material together (forming the Sun) • Planets formed from remaining materials

  3. Ancient Earth What was it like? • Atmosphere contents: • Ammonia, H2O vapor, Methane (CH4), CO2 • Climate: • Extreme heat due to meteor impacts & volcanic activity • Eventually Cooling: Water vapor condensed (oceans formed) Click on picture to play video clip

  4. Organic Molecules 1. Miller - Urey Experiment • Hypothesis: Energy from lightning created organic materials from inorganic ingredients • Experimental Set-Up: • Ammonia, H2O vapor, Methane, CO gases added • Electricity added (simulate lightning) • Result: Amino Acids & later nucleotides were created

  5. 2. Meteorite Hypothesis • Hypothesis: Amino acids may have arrived on Earth through meteorite or asteroid impacts. • Fun Fact! 90 amino acids were found from this meteorite, only 19 of them can be found on Earth. Murchison Meteorite

  6. Early Cell Formation • Lipid membrane hypothesis • Liposomes • Spheres of lipids • Can form around organic molecules • Hypothesis: 1st cell membranes??????

  7. Early Genetic Material • A hypothesis proposes that RNA was the first genetic material. • Ribozymes are RNA molecules that catalyze their own replication. • DNA needs enzymes to replicate itself. • Because of this, scientists think that DNA evolved from RNA

  8. Eukaryotic Cell Formation • Endosymbiosis is a relationship in which one organism lives within the body of another. • Mitochondria and chloroplasts may have developed through endosymbiosis.

  9. Multicellular Life & Biodiversity • Evolution of sexual reproduction led to increased diversity/variation. • Sexual reproduction may have led to multicellular life.

  10. ReviewThese are questions that I would ask you on the test, so you should do your best at answering them accurately and completely. • What is a nebula? • What does the nebula hypothesis try to explain? • What materials/ingredients did Miller & Urey use in their experiment? Why these and not other ingredients? • Why was Miller and Urey’s experiment of great importance? • How did eukaryotic cells form? • How would sexual reproduction lead to diversity and multicellular life?

More Related