hyaline layer https://github.com/geneontology/go-ontology/issues/29475 cellular_component A multilayered extraembryonic matrix that functions as a substrate for cell adhesion through early development. It is thought to protect and lubricate the embryo, stabilize the blastomeres during morphogenesis, and regulate nutrient intake. The major constituent of the hyaline layer is the protein hyalin. This matrix has been found in echinoderms. GO:0033166 specialized extracellular matrix