Question

A scientist claims that after the first single-celled organisms formed on Earth, conditions would not sustain multicellular organisms for millions of year. Which statement provides the STRONGEST evidence to support this claim
A.Earth's early atmosphere lacked oxygen, which multicellular organisms need to break apart food

B.Earth's early atmosphere lacked nitrogen, which multicellular organisms need to synthesize proteins

C.Earth's surface was much too hot to support liquid water, which multicellular organisms need to survive

D.Earth's surface was much too cold to support liquid water, which multicellular organisms need to survive

Answer 1

Answer:

A.Earth's early atmosphere lacked oxygen, which multicellular organisms need to break apart food

Explanation:

One important feature that led to the development of multicellular organisms was the rise of oxygen-producing photosynthetic bacteria. Prior to this development, the unicellular organisms (anaerobes) then present on Earth obtained energy from inorganic fuels.

However, with the presence of oxygen in the atmosphere, a shift was observed as organisms that could obtain energy from the reduction of energy became predominant. This unicellular aerobes later paved way for the evolution of multicellular aerobes.