In the endogenous respiration concept the biodegradable fraction of X OHO is regarded as a homogenous substrate that undergoes self-destruction in the absence of external substrate. The degradation process of X OHO is modelled with Eq. (4) and Eq.xperimental evidence for the validity of the endogenous respiration model comes from Marais and Ekama (1976) . Using the OUR method, the value of b OHO was found to be 0.24 d â1 and independent from SRT in the range of 2.5â30 days. Similar results were obtained by van Haandel et al.
1 Basal cells: These cells are in the lower part of the epidermis, called the basal cell layer. 2  These cells constantly divide to form new cells to replace the squamous cells that wear off the skinâs surface.3  As these cells move up in the epidermis, they get flatter, eventually becoming squamous cells.he main types of cells in the epidermis include: 1  Squamous cells: These are flat cells in the outer part of the epidermis that are constantly shed as new ones form. 2  Basal cells: These cells are in the lower part of the epidermis, called the basal cell layer.
Differentiation of Keratinocytes: Keratinocyte stem cells reside in the basal layer of the epidermis, which is the lowest layer of the stratified epithelia. These cells divide to give rise to transient amplifying cells which divide further, and differentiate, as they move upwards in the epidermis.quamous keratinocytes are also found in the mucosa of the mouth and esophagus, as well as the corneal, conjunctival, and genital epithelia. These cells are responsible for forming tight junctions with the nerves of the skin. They also keep Langerhans cells of the epidermis, and lymphocytes of the dermis, in place.