Mushrooms

The element that distinguishes fungi from animal is the presence of cell walls and vacuoles, which in turn brings them closer to plants.

An excerpt from the article 22 facts about Mushrooms

Fungi do not carry out photosynthesis, the cell walls of most fungi contain chitin, which is not found in plants, while it is characteristic for the exoskeleton of arthropods. Mushrooms don't make cellulose either.

Each part of the fungal organism is self-sufficient and there is no communication between them.