Conditions on the early Earth could have produced very simple cell in what four stages? ------ 1. Abiotic (non-living) synthesis of small organic molecules2. Monomers joined to find polymers3. Molecules surrounded by a membrane formed protobions4. Self replicating molecules
What are two examples of monomers? ------ 1. Amino Acids2. Nucleotides
What are two examples of polymers? ------ 1. Proteins2. Nucleic Acids
What two scientists performed an experiment that simulated the earth's early atmosphere? ------ Miller and Urey
From their famous experiment to simulate earth's early atmosphere, what did scientists Miller and Urey mistakenly conclude? ------ They found earth's early atmosphere to be reducing, however this is now thought to be unlikely
What significant finding did scientists Miller and Urey make after simulating earth's early environment? ------ Abiotically synthesized amino acids
What are protobions? ------ Precursors to cells; these are abiotic structures
Name two characteristics required for life ------ 1. Metabolism2. Reproduction
Why was RNA and not DNA most likely the first genetic material? ------ RNA was single stranded, meaning it could adapt to many 3D shapes. As such, the shape that could replicate the best survived.
What are ribozymes? ------ RNA molecules that have enymatic functions and can replicate themselves
Based on the decay of radioactive isotopes, what is used to determine the age of fossils? ------ Radiometric dating
Which eon occurred from 4.6 billion to 2.5 billion years ago? ------ Archaean
Which eon occurred from 2.5 billion to 542 million years ago? ------ Proterozoic
Which eon has occurred from 542 million years ago to the present? ------ Phanerozoic
When was the formation of the Earth? ------ 4.6 billion years ago
When were the first prokaryotes? ------ 3.5 billion years ago
What is the name of the layered rocks that contain the oldest known fossils? ------ Stromatolites
When did the oxygen revolution occur? ------ 2.7 billion years ago
What geological features are evidence of oxygen on early earth? ------ Banded iron formations
Oxygen was first produced by what? ------ Cyanobacteria
When were the first eukaryotes? ------ 2.1 billion years ago
What were engulfed first, mitochondria or plastids and why? ------ Mitochondria because all eukaryotes have mitochondria but not all have plastids (only plants have plastids)
What is the theory of endosymbiosis? ------ Prokaryotes engulfed other prokaryotes to create organelles like mitochondria and plastids. Thought to be serial because it happened in steps.
Name evidence that supports the theory of endosymbiosis ------ Mitochondria have enzymes, replication processes, and plasma membranes like modern prokaryotes
When did multicellular eukaryotes first arise? ------ 1.5 billion years ago
When did the colonization of land by fungi, animals, and plants occur? ------ 500 million years ago
What was the seemingly rapid appearance of most major groups of complex animals around 530 million years ago? ------ The Cambrian Explosion
What is the theory that Earth's surface was nearly or entirely frozen at some points in the past? ------ The Snowball Earth hypothesis
