Question

How are carbohydrates broken down?

Answer 1

Complex carbohydrates like starch are broken down into simpler carbohydrates like glucose by hydrolyzing enzymes.

Explanation:

Plants store carbohydrates in form of starch, a polysaccaharide. Starch is broken down into glucose in a series of steps catalyzed by hydrolyzing enzymes, like amylase.

Starch may be broken down into glucose -1-phosphate by enzyme starch phosphorylase in presence of water.

Animals store carbohydrates in form of glycogen in liver. It is converted into glucose in presence of hormone insulin and added into blood.

Blood carries glucose to all the living cells, in which it acts as respiratory substrate. It is broken down into `CO2` and `H2O` in presence of `O2` present in combined form with haemoglobin.

Glucose ( `C6H12O6` ) acts as respiratory substrate and is broken down into `CO2` and `H2O` in aerobic respiration.

In anaerobic respiration, glucose is broken down into either
ethanol and `CO2` or lactic acid only, depending upon the presence of enzyme alcoholic dehydrogenase or lactic acid dehydrogenase, respectively.