Question

Aminopeptidase, digestive enzyme catalyzes the cleavage of:
A. Dipeptides
B. Smaller peptides
C. Peptones
D. Amino acids

Answer 1

Enzymes are the biological molecules that are made up of proteins. These act as biological catalysts that speed up the reactions going on in our body to a great extent and convert the substrates into desired products. They basically lower the activation energy of a reaction, so that reaction gets completed in less time and requires less energy than before.

Step by step answer: Enzymes are biological catalysts that are proteinaceous in nature. These convert the substrate into products by lowering the activation energy of that reaction. There are numerous enzymes that catalyze specific reactions of the body. These are grouped on the basis of the function they perform.
Out of which the peptidases is a category of enzymes that are responsible for the cleavage of the amino acids from the protein chains or peptides. Further, peptidases are of two types, endopeptidases and exopeptidases. The endopeptidases are responsible for cleavage within the amino acids of the protein chain whereas the exopeptidases cut or remove the amino acids from the ends of the protein chains.
Aminopeptidase is a type of peptidase. These enzymes cleave the N-terminal or amino terminal of the protein chain. These are found in a wide variety of cellular organelles like cell membrane and the cell cytoplasm found in animals and plants. Whereas, Dipeptides are cleaved by a particular type of peptidase called dipeptidyl peptidase from a polypeptide chain. These are basically found to stimulate the release of enzyme gastrin from the G-cells present in the stomach.
Smaller peptides are usually made up of a few protein residues. Thus, these do not require any specialized type of enzyme to cause their breakdown. Therefore, smaller peptides are broken down with the help of enzyme proteases.
Peptones are the soluble proteins that are made in early stages of digestion of proteins.
Hence option A is correct.

Note: There are numerous enzymes that exist in our body, therefore to make it easier to remember these enzymes are named by adding the suffix –ase to the substrate name. As the enzymes are specific for every reaction, these are named after the substrate. For example, enzymes catalyzing the breakdown of urea is called urease.