Question

The early organisms on earth also needed to break down glucose to generate energy to survive. Which of the following processes did they most likely use?

A) Photosynthesis
B) Anaerobic respiration
C) Aerobic respiration

Answer 1

Anaerobic respiration bc no oxygen

Answer 2

Anaerobic respiration.

Step-by-step explanation:

The first life has been evolved on earth around 3.4 billion years ago. The earth's primitive environment is highly reducing, thunder and lightning is common.

Anaerobic respiration is the respiration that takes place in the absence of oxygen. The early organism break down their glucose by the anaerobic respiration to survive as no oxygen is available in the primitive earth's atmosphere.

Thus, the correct answer is option (B).