I have read in books that Proteins and Peptides are fundamental components of cells which carryout important biological functions.Can any one explain me the structural difference between Proteins and Peptides?

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1 Answer 1


In terms of structure: both are composed of amino acids.

A peptide is when at least two amino acid are linked together. A protein is composed of multiple amino acids and have a secondary, tertiary and even quaternary structure.

In terms of function: larger molecules have more complex functions.

Peptides can act as a intracellular or extracellular ligands which will activate a signal.

Proteins have a large array of functions (enzymatic, structural, receptors etc)

This article explains in more details the differences in proteins structure and functions:https://en.wikibooks.org/wiki/Structural_Biochemistry/Proteins

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