Origin of cells topic 1.5

Question 1

Abiogenesis

Answer 1

The formation of living cells from non-living materials

Question 2

abiogenesis is theorized to involve 4 four key processes:

Answer 2

• Non-living synthesis of simple organic molecules
• Assembly of organic molecules into complex polymers
• Formation of polymers that can self-replicate
• Packaging of molecules into membranes to create an
  internal chemistry different from the surroundings

Question 3

Biogenesis

Answer 3

The principle that living organisms are produced only from other living organisms.

Question 4

Oxygenation of Earth

Answer 4

The appearance of photosynthetic organisms lead to the
rapidly increasing oxygenation of the Earth’s environment

Question 5

Oceans

Answer 5

• Originally, Earth’s oceans had high levels of dissolved
  iron (released from crust by underwater volcanic vents)
• Oxygen chemically reacted with the iron to form an
  insoluble precipitate (iron oxide)

Question 6

Rock Deposition

Answer 6

• Insoluble iron formed banded iron formations (BIFs)
• These deposits are not commonly found in rock that is
  younger than 1.8 billion years (hence, identifies when
  photosynthetic organisms first evolved)

Question 7

Atmosphere

Answer 7

• When dissolved iron was completely consumed, oxygen
  started accumulating in the anoxic atmosphere