The spontaneous origin of life on Earth

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The spontaneous origin of life on Earth

• Branched Timeline Activity
• Complete the diagram on the next slide

2
Spontaneous origin of life

• Four essential processes
• the non-living synthesis of simple organic
  molecules
• the assembly of these molecules into polymers
• the origin of self-replicating molecules that
  made inheritance possible
• the packaging of these molecules into membranes
  with an internal chemistry different from their
  surroundings.

3
UV radiation lightning
the Earths atmosphere contained nitrogen,
water vapour and carbon dioxide smaller
amounts of methane, ammonia, carbon monoxide,
sulphur dioxide, hydrogen sulphide and hydrogen
cyanide.
Describe the evidence from Miller and Ureys
experiments
Non-living synthesis of organic molecules
What recent evidence suggests that Comets
brought complex organic Compounds to Earth
? . . ....
complex organic compounds e.g. glucose, .
............................................ a
dd some of your own
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Formation of Protobionts
Identify what is needed for each of the steps
below
The polymers exist in small packages which become
different from the surroundings
Larger molecules Polymers, big enough to have
biological functions
Inheritance of the molecules is now possible
Organic Molecules
If some of the organic molecules function as
Causing .
If some molecules form primative .
.. That hold the Polymers in one place
If a polymer of RNA is surrounded by a
and it replicates and then the
membrane . Into two loops..
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Summary what you have to know

• Outline the experiments of Miller and Urey into
  the origin of organic compounds.
• State that comets may have delivered organic
  compounds to Earth.
• Discuss possible locations where conditions would
  have allowed the synthesis of organic compounds.
• Outline two properties of RNA that would have
  allowed it to play a role in the origin of life.
  Include the self-replicating and catalytic
  activities of RNA
• State that living cells may have been preceded by
  protobionts, with an internal chemical
  environment different from their
  surroundings.Examples of Protobionts include
  coacervates and microspheres.
• ToK "falsification of hypothesis" is a problem
  for many of these theories.Scientists cant
  actually travel back in time 4000 million years!
• The ability to test if the hypothesis is false is
  an essential ingredient of Science.
• The idea of Creation is not Scientific because
  it can never be tested.