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16 questions
Why do many scientist believe that free oxygen was not present in early earth's atmosphere?
Free oxygen could not have been present because there were no plants to produce it
Free oxygen would have reacted with and destroyed organic molecules as they formed
Free oxygen was not needed for a living cell to assemble from nonliving materials
Free oxygen would have escaped from the early atmosphere into space due to high temperatures
In what way are protocells similar to living cells?
They have a semipermeable membrane and can grow and divide
They contain genetic material
They have a phospholipid bilayer
They contain true proteins similar to the ones found in living cells
According to the theory of endosymbiosis, how did cells acquire mitochondria?
A eukaryotic cell engulfed a virus
A large aerobic cell engulfed a chloroplast
A large anaerobic cell engulfed a small aerobic bacterium
A large anaerobic cell engulfed a photosynthetic bacterium
According to theory of endosymbiosis, how did plant cells evolve
An anaerobic cell engulfed a chloroplast
An aerobic, eukaryotic cell engulfed a photosynthetic bacterium
An anaerobic cell engulfed a small aerobic bacterium
A large anaerobic cell engulfed a photosynthetic bacterium
How are mitochondria and chloroplasts like bacteria cells?
They divide by meiosis
They can make their own food
They have the same membrane-bound organelles
They contain their own DNA
What was formed in the Miller-Urey experiments?
amino acids
proteins
living cells
DNA
True or False. Nucleotides could have been brought to Earth from a meteorite in the form of nucleobases billions of years ago.
True
False
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