Question

What is the first metabolic pathway to evolve?

Answer 1

Glycolysis:

1. Glycolysis is considered to be the first metabolic pathway to be evolved.
2. Glycolysis is a ten steps process of breakdown of glucose molecules to produce energy in the form of ATP, NADH, pyruvate, and water. the process is carried out in the cytoplasm.

Reasons for glycolysis to be considered the most ancient metabolic pathway are:

1. Glucose is used by every living organism as a source of energy thus glucose breakdown by glycolysis is important even in the most ancient primitive living beings.
2. Glycolysis is not dependent on oxygen as it is found in both aerobes and anaerobes. It is considered that early Earth's atmosphere does not have oxygen thus other metabolic pathways cannot be present at the time.
3. Glycolysis is a common pathway among the eukaryotes and prokaryotes.