Describe the two theories for how life began on earth:
• the two theories are called panspermia and formation of chemicals on earth
• Gravity pulled down meteorites, causing organic molecules to be present on earth
Formation of Chemicals on Earth
• Life began here on earth by the formation of organic molecules. The early earth environment had no free oxygen and therefore was a good environment for the formation of organic molecules in the primordial soup
Identify the theory that Oparin formulated to explain the formation of organic molecules on earth. (chemosynthesis theory)
• Oparin formulated the ...view middle of the document...
The sediment above it must harden, and a cast must be formed. This occurs when water washes through and dissolves bones. The minerals must be left behind and take the place of the bones. The chances of there being perfect conditions for this to take place are highly unlikely. Chances of predation, being squashed under sediment are far more probable. Therefore, it is a rarity that the conditions for fossilization to occur.
The earth is dynamic and ever changing
Early life is believed to hve originated under anoxic (no oxygen) conditions
-oxygen wastes given off early life autotrophs helped to form our oxygen rich atmosphere. These were called stromadalites
iron oxide deposits in ancient rock are evidence of early life because there was no oxygen, then there became oxygen.
life continues to effect the earth
Explain why prokaryotes are the most predominant organisms on earth
Prokaryotes are single-celled organisms, which means they can survive in extreme environments. Examples are thermophiles, halophiles. Examples of environments are hotsprings
Explain why the environment in which prokaryotes are found gives evidence for them being the first organisms on earth
They are found in extreme oxic environments, which may have been similar to early earth, proving that they were likely one of earth’s first organisms.