Bio studying
Four stage hypothesis
1 Abiotic synthesis of organic molecules.
2 joining of the molecules into polymers
3 Promotions formed able to maintain internal chemistry different from that of
outside environment
4 origin of self replicating molecules allowed inheritance to occur
Yuri and Miller created Yuri Miller hypothesis. Explains how molecules may have been
made. Have water heat it and allow to evaporate inside of closed system. Molecules are
present that may have been present in the early environment. Sparks to simulate
lightening. Checked water as condensed and cooled for possible molecules. Found simple
amino acids
Not sure whether early environment had enough methane and other compounds to make
molecules. Believed may have first been created in hydrothermal vents. Alvin sent to
check it out. May have come from meteorite that hit earth
Believed that protobionts may have been abiotically synthesized. Phospholipids form
distinct shapes when placed in water because of hydrophobic and hydrophilic regions.
Take up water from environment and can have charges in their membrane. Discharge in
nerve like fashion. If random amino acids present when the protobionts formed then
could have resulted in molecule that could selectively take in certain molecules. With
metabolism and simple replication could have created first organisms.
Riboszymes RNA molecules that are able to make complimentary molecules if the right
nucleotides are present.
Dating methods
Index fossils used to date strata of unknown age. For example, look at strata that contain
fossils of organisms that were very wide spread for a period of time. Known strata w/
abundant fossils of organisms know how old these fossils are. Use this layer of strata to
look when started to disappear and can tell when strata may have formed or tell if above
sea level by absence of sea fossils.
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- Spring '08
- Cooper
- Bacteria, RNA, Organic Molecules, RNA molecules
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