15.1 + 15.2 + 15.3 Conditions on Earth -> Origin of Life, Experiments of Abiotic Synthesis of Organic Molecules, Origin of First Cell Flashcards
Stromatolites
layered rock that results from the activities of prokaryotes (such as bacteria) that bind the thin films of sediment together
From the time of Ancient Greeks to the 1800s people believed that living organisms came from
nonliving matter (Flies from meat; fish from ocean mud)
Why do scientists argue that there is no synthesis of organic compounds in the Earth today?
bc it is rich in oxygen (oxidizing agent) which disrupts chemical bounds
What was the early atmosphere of Earth like?
The early atmosphere (before photosynthetic organisms added O2 to the atmosphere) was electron adding
What did the electron-adding atmosphere of Earth do?
provided energy for the abiotic synthesis of organic organisms
Miller Urey Experiment
tried to recreate the early atmosphere and create life
What did the flask of warmed water represent in the Miller Urey Experiment?
ocean
What did the higher flask represent?
atmosphere
What was in the higher flask?
water vapor, hydrogen, methane, ammonia, and electrodes
What did the electrodes represent?
lightning (as an energy source)
What did the condenser do
changed the vapor to rain
Was there oxygen in the early atmosphere
no
How many steps are including in the Miller Urey Experiment?
4
What are the 4 steps included in the Miller Urey Experiment?
1) Water is warmed and becomes water vapor
2) The water vapor moves into the atmosphere flask
3) The condenser rained water and any dissolving compounds down to the sea
4) Water samples were periodically collected
What was found from the Miller Urey Experiment?
found organic molecules
What organic molecules were found from the Miller Urey Experiment?
monomers such as amino acids
Was life found from the Miller Urey Experiment?
no
What was the final conclusion that Miller and Urey made from their experiment?
organic macromolecules can come from inorganic molecules
How many parts are there to the origin of the first cell?
3
What are the 3 parts of the origin of the first cell?
1) Abiotic Synthesis of Polymers
2) Formation of Protocells
3) Self Replicating RNA
Can monomers join and form polymers without enzymes?
Yes, through the abiotic synthesis of polymers
How many steps are in the experiment of abiotic synthesis of polymers?
3
What are the 3 steps of the experiment of abiotic synthesis of polymers?
1) Put nucleotides into water
2) Put onto a hot rock, clay, or sand
3) The heat vaporizes the water and concentrates the monomers, joining some into polymers
When may have the abitotic synthesis of polymers happened in early earth?
on lava rocks
How were organic molecules isolated within an enclosed membrane
through the formation of protocells
What was the experiment used to prove the formation of protocells
Vesicles were formed when lipids are mixed with water
Vesicles
small membraine-enclosed sacs
protocells
structures that are formed from the cluster of abiotic material and were able to remain stable and reproduce in their environment
How many steps are there in the formation of protocells?
3
What are the steps in the formation of protocells?
1) Researchers add a type of clay that they thought was present in the early Earth
2) Vesicles began to form at a faster rate
3) Organic molecules are also more concentrated on this clay, so interact more with vesicles
What were the first genes like?
self replicating RNA
What did people use to think the molecule of life was?
People used to think that RNA was the molecule of life bc it is more stable and has less mistakes than DNA
How many steps are included in self-replicated RNA
3
What are the 3 steps that are included in self-replicated RNA?
1) RNA monomers adhere to clay particles and become concentrated
2) Monomers spontaneously form the “first genes”
3) RNA complementary chains form
Short RNA molecules can assemble from
RNA polymers
Ribozymes
RNA molecule that acts as an enzyme, catalyzing monomers -> polymers + replication
