for a given structure , a period of maximal sensitivity to thyroxine exists which corresponds to the period of development during which that structure undergoes its main morphological changes ( i.e . from 6 to 13 days for the inner sulcus epithelium , the first postnatal week for the tectorial membrane , from 6 to 10 days for the pillars and the tunnel of corti , the second and probably a part of the third postnatal week for outer hair cell synaptogenesis ) .
C0014609
epithelium
C1518683
outer hair cell