Intercellular spaces are the small gaps or areas between cells in tissues. These spaces play a crucial role in allowing the exchange of nutrients, waste products, and signaling molecules between cells. They help maintain tissue structure and function by providing a pathway for communication and transport. In plants, intercellular spaces can be found in the mesophyll tissue, where they facilitate gas exchange during photosynthesis. In animals, these spaces are important for the movement of fluids and immune cells, contributing to overall health and tissue repair.