ORIGIN OF LIFE- WHAT IS THE
EVIDENCE?
QUICK CHEMISTRY REVIEW:
To understand the origin of life (ORIGIN OF CELLS) you must understand how
matter is organized!!!!
• Element: a substance that cannot be broken down into simpler chemical
substances.
• Atom: smallest particle of an element that still has the properties of that
element.
Nucleus: center of an atom.
 Atomic nuclei are composed of 2 subatomic particles:
Protons:  Positively charged
 The number of protons determines the
identity of an element.
Neutrons:  Neutral charge
 Same size as protons
Electrons:  Negatively charged particles that
orbit the nucleus in an electron cloud
outside the nucleus

• Compound: substance
composed of
that have been
combined chemically
• To go from
to
, you need to
make bonds…
• Which means you must PUT
IN ENERGY somehow!
small
small
BIG
(photosynthesis is one example of this)
HOW DID LIFE EMERGE FROM NON-LIVING
MATERIALS ON EARLY EARTH?
•sterile
•UV radiation
•hot
•meteorites
•volcanic
•storms & lightning
Brief Overview of Inorganic to Organic Life on Earth
The Oparin-Haldane hypothesis
•
•
Early atmosphere came from volcanoes
WHAM!
•
•
•
•
Water
Hydrogen
Ammonia
Methane
Aleksandr Oparin and J. B. S.
Haldane suggested in the 1920s
that these small molecules could
have formed more complex
molecules under early Earth
conditions.
NO
OXYGEN!
Results:
End: big,
complex
molecules
Start: small, simple
molecules