In which phase of cellular respiration is glucose a substrate

Glucose is a substrate in glycolysis phase.

Explanation:

Cellular respiration is metabolic process which take place in cells of organism to convert energy from nutrients like glucose to Adenosine triphosphate (ATP) and release some waste substances.

Glucose is used in glycolysis phase as substrate and it is converted to ATP and pyruvate. Pyruvate is the utilised in keep cycle to produce energy.

Glucose is majorly used in cell to produce energy.