Final answer:
Proteins are organic compounds made up of amino acids. They can vary widely in size and shape, and their shape and size are critical to their function.
Step-by-step explanation:
Proteins are organic compounds made up of amino acids. They can vary widely in size and shape. Small proteins may contain just a few hundred amino acids, while larger proteins can have thousands or even tens of thousands of amino acids. The shape and size of a protein are critical to its function, and different proteins have different shapes and chemical properties. For example, hemoglobin is a globular protein, while collagen is a fibrous protein.