Proteins are large, complex molecules made up of long chains of amino acids. They perform a vast array of functions in cells, including:
* enzymes: Catalyze biochemical reactions
* Structural components: Provide support and shape to cells and tissues
* Hormones: Act as chemical messengers
* anticorps: Defend the body against infection
* Transport proteins: Carry molecules across cell membranes
* protéines contractiles: Enable muscle movement
