Which statement best supports the hypothesis that glycolysis is an ancient metabolic pathway that originated before the last universal common ancestor of life on Earth?
A) Glycolysis is widespread and is found in the domains Bacteria, Archaea, and Eukarya.
B) Glycolysis neither uses nor needs O₂.
C) Glycolysis is found in all eukaryotic cells.
D) The enzymes of glycolysis are found in the cytosol rather than in a membrane-enclosed organelle.
E) Ancient prokaryotic cells, the most primitive of cells, made extensive use of glycolysis long before oxygen was present in Earth's atmosphere.

Question

Quizplus · Accepted Answer

The fact that glycolysis is found in all three domains of life suggests that it existed before the last universal common ancestor of life on Earth and has been conserved throughout evolution.

Answer: B 
 The fact that glycolysis does not utilize or require O₂ implies that it evolved before the development of oxygenic photosynthesis, which was a significant evolutionary event that introduced oxygen into Earth's atmosphere.

Answer: D 
 The enzymes of glycolysis are found in the cytosol rather than in a membrane-enclosed organelle, indicating that it likely evolved before the development of eukaryotic cells, which are characterized by compartmentalization of metabolic processes within organelles.

Which Statement Best Supports the Hypothesis That Glycolysis Is an Ancient