Evolution
Final Exam
Final Exam
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Flashcards
Formation of the Universe?
13.7 billion years ago
Theories about the Origin of the Universe
How big is the Universe?
Infinite, no boundaries visible
Ordinary Matter (baryons)
Dark Matter
Dark Energy
Current View of the Universe
When did the Solar System Form?
4.6 billion years ago
What is the prevailing scientific theory on the Formation of the Solar System?
Condensation Theory. The sun and the planets condensed from a cloud of dust and gas from gravitational attraction.
How did solar winds shape our Solar System?
It made the rocky planets stay closer to the sun, and the gas planets to be further away.
The Inner Core of our Earth Consists of...
The Outer core of our Earth consists of...
What is the Mantle composed of...
Malleable Rocks
What is the Crust Composed of?
Lighter rock (silicates)
First Atmosphere composition
Did the first atmosphere last?
No, the first atmosphere was lost due to out-gassing
When did the second atmosphere arise?
4.2 to 3.8 billion years ago
What was important about the second atmosphere?
It was a "Reducing atmosphere" so abiotic synthesis of organics was possible
The first oceans had...
Three view of where life originated...
What is life?
What is life? (Continued)
Why the Earth favored life?
Stanley Miller Experiment
What are important precursors to life?
Aldehydes and cyanides
How could organic molecules survive?
They had to become more complex with the help of polymerization reactions.
How could the polymerization of simple organics take place?
Well polymerization reactions are just dehydration reactions, so tides of water most likely washed up molecules on top of shorelines or clays, and when the water is taken away between the two molecules then they become bonded together. These bonded molecules then were washed back into the ocean.
Alternative way of Polymerization?
Aldehydes and cyanides may be condensing agents
What is the reason that life started at Hydrothermal vents
More than 100 vents are known and also ancient prokaryotes were thermophiles.
Models for protobionts
What does the Coacervate model contain?
When many macromolecules get together and are suspended because of charge differences. They form spontaneously in the lab in water and the membrane is selectively permeable. Also able to grow and fragment.
What were the metabolic pathways within Coacervates.
The membrane allows for a environment to be made within the cell that allows for reactions to take place. Starch to Maltose
Proteinoid model
Dry amino acids heated to 130-180 Centigrade form a double membrane, which is selectively permeable.
Liposome model
Phospholipids, forms micelles spontaneously, and form bilayers like cell membrane, which can incorporate proteins and other molecules.
Properties of Liposome model
Able to trap substances within and create a internal differing chemical environment.
Clay-Vesicles and Protobionts?
Montmorillonite is a chemical catalyst. Formed by air bubble under clay form a bubble that has a selective permeable membrane.
What do the Protobiont models prove?
Spontaneous self-assembly of macro-molecules can produce complex structures.
What can make a molecule more complex?
Natural Selection
How did natural selection select for more complex molecules?
Each molecule interacted with the same environment, therefore there is a competition between resources out in nature and so the ones that could metabolize where selected. Also shapes that where the ones that could exist stayed on and that is possibly how early inheritance started.
Which protobiont is selected for?
One that requires the fewest precursors and can synthesize the greatest number of products
