Final answer:
Collagen is a structural protein in the extracellular matrix that plays a crucial role in tissue formation and intercellular communication.
Step-by-step explanation:
An example of a structural molecule found in the extracellular matrix (ECM) is collagen. Collagen provides tensile strength and is interwoven with proteoglycans, which are glycoprotein molecules containing carbohydrates. The ECM is essential for not only holding cells together to form tissues but also facilitating communication among cells. This communication is possible as the ECM interacts with cell surface receptors and signaling molecules, transmitting signals into the cells, which can trigger various cellular responses.