Which of the following statements is not true about carbohydrate structures?

The statements which are not true of carbohydrates are mentioned below:

Triglycerides are the most common type.

Certain carbohydrates are enzymes or catalysts.

Triglycerides are lipid or fat present in the human blood. Excess of calories converted in to triglycerides and are stored in the cells. Excess of triglycerides harden arteries which may cause heart diseases.

Most of the hormones are peptides or amino acid derivatives and some hormones are steroid derivative of cholesterol.