Fibre Ultrastructure

  • Jeffrey E. PlowmanEmail author
  • Duane P. Harland
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1054)


Mammalian hair fibres can be structurally divided into three main components: a cuticle, cortex and sometimes a medulla. The cuticle consists of a thin layer of overlapping cells on the surface of the fibre, constituting around 10% of the total fibre weight. The cortex makes up the remaining 86–90% and is made up of axially aligned spindle-shaped cells of which three major types have been recognised in wool: ortho, meso and para. Cortical cells are packed full of macrofibril bundles, which are a composite of aligned intermediate filaments embedded in an amorphous matrix. The spacing and three-dimensional arrangement of the intermediate filaments vary with cell type. The medulla consists of a continuous or discontinuous column of horizontal spaces in the centre of the cortex that becomes more prevalent as the fibre diameter increases.


Fibre surface cuticle lipids Exocuticle Endocuticle Cortex Medulla Cell membrane complex Cytoplasmic/nuclear remnant 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.AgResearch Ltd.LincolnNew Zealand

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