stratum granulosum
Last reviewed 01/2018
The stratum granulosum is the skin layer deep to the stratum lucidum but superficial to the stratum spinosum. During their ascent, cells here become flatter as a result of pressure from below.
Cells of the granular layer are characterised by basophilic keratohyaline granules which stain with haemotoxylin. With ascent, these granules merge with tonofibrils to form keratin and its surrounding matrix.
They also contain large numbers of lysosomes used for destruction of intracellular organelles during ascent.