Tissue layers are the different layers of cells that make up an organism's tissues. The three crossword solutions for the term 'tissue layers' are plies, telae, and membranes. Plies are the layers of tissue that are arranged in a parallel fashion. Telae are the thin layers of tissue that separate the plies. Membranes are the thin layers of tissue that cover the surface of an organ or tissue. Together, these three layers form the tissue layers of an organism.