Zymogen is inactive enzymes example.
1. procarboxypeptidase
2.chymiotrypisinogen
3.angiotensinogen

but amylase is active.

Introduction:
Zymogens, also known as proenzymes, are inactive forms of enzymes that are converted into their active forms through various biochemical processes. This conversion is important to prevent the enzymes from causing damage to the tissues where they are produced. Zymogens are typically secreted in an inactive form and are activated under specific conditions when they are needed.

Explanation:
Among the options provided, amylase is the only enzyme that is not secreted in the form of a zymogen. Let's explore the other options in detail to understand why they are secreted as zymogens.

Carboxypeptidase:
Carboxypeptidase is an enzyme involved in protein digestion. It is secreted in the form of a zymogen called procarboxypeptidase. This zymogen is activated in the small intestine by the enzyme trypsin, which cleaves off a small peptide segment to convert it into its active form.

Chymotrypsin:
Chymotrypsin is another enzyme involved in protein digestion. It is secreted as a zymogen called chymotrypsinogen. In the small intestine, chymotrypsinogen is activated by trypsin, which removes a small peptide segment to generate active chymotrypsin.

Angiotensin:
Angiotensin is not an enzyme but a peptide hormone involved in regulating blood pressure. It is produced in an inactive form called angiotensinogen. Angiotensinogen is converted into angiotensin I by the enzyme renin, and subsequently, angiotensin I is converted into angiotensin II by the enzyme angiotensin-converting enzyme (ACE).

Amylase:
Amylase is an enzyme involved in the digestion of carbohydrates. Unlike the other options, amylase is not secreted as a zymogen. It is produced and secreted in its active form directly.

Conclusion:
In summary, among the options provided, amylase is the only enzyme that is not secreted in the form of a zymogen. Carboxypeptidase, chymotrypsin, and angiotensin are all secreted in the form of zymogens, which are converted into their active forms under specific conditions. This activation process helps regulate the activity of these enzymes and prevents them from causing damage to the tissues where they are produced.