Exercises
What are respiratory substrates? Name the most common respiratory substrate.
Respiratory substrates are the organic compounds that are oxidised during the process of cellular respiration to release energy in the form of ATP.
These compounds include carbohydrates (glucose, starch, sucrose), fats (fatty acids and glycerol), proteins (amino acids after deamination), and organic acids. Each substrate enters the respiratory pathway at a different point — fats enter as acetyl CoA, proteins enter as pyruvate, acetyl CoA, or intermediates of the Krebs' cycle, depending on the amino acid.
The most common (favoured) respiratory substrate is glucose (a hexose sugar). All other carbohydrates are first converted to glucose before being used for respiration.
Answer: Respiratory substrates are organic compounds oxidised during cellular respiration to yield energy. Glucose is the most common respiratory substrate.