Liver hepatocytes. Image provided by Jim Burchette HT(ASCP).
The liver parencyma is the functional part of the liver. Hepatocytes (epithelial cells of the liver) give rise to the basic structure and function of the liver. The epithelial cells of the liver are grouped together to form functional units referred to as liver lobules. The hepatocytes are where most of the synthesis and degradation functions occur within the liver.
Liver lobules form functional units seen histologically as a polygonal mass of hepatocytes (epithelial cells). In human liver tissue, liver lobules are arranged closely which make it difficult to differentiate where lobules begin and end. However, some liver lobules can be distinguished by surrounding connective tissue containing other tissue elements such as ducts, vessels or nerves referred to as portal spaces.