A long chain of amino acids forms a polypeptide , and when one or more polypeptide chains fold into a functional 3D shape, the molecule is called a protein.

Quick Scoop: The Core Idea

  • Amino acids are like individual beads.
  • When many amino acids link together, they form a polypeptide chain.
  • One or more folded polypeptide chains make a protein – a major biological macromolecule in living things.

So, for the exact question “what type of molecule is made from a long chain of amino acids?” the standard school/quiz answer is:

A long chain of amino acids is called a polypeptide (and a functional long chain or chains is a protein).

Tiny Story To Remember It

Imagine building a necklace:

  1. Each amino acid is a single bead.
  2. Linking beads together with string is like forming peptide bonds.
  1. The whole necklace (many beads in a row) is your polypeptide chain.
  2. When that necklace twists and folds into a specific shape, it becomes a protein that can actually “do a job” in the cell.

TL;DR:
The molecule made from a long chain of amino acids is a polypeptide (and when properly folded, it is a protein).

Information gathered from public forums or data available on the internet and portrayed here.