the outer segment of the principal rod is 29.8 +/- 0.6 micrometers long and 6.4 +/- 0.6 micrometers in diameter , whereas the outer segment of the minor rod is 19.7 +/- 3.4 micrometers long and 4.5 +/- 0.6 micrometers in diameter , the latter accounting for approximately 2-3 % of the total rod photoreceptor population .
C0035798
outer segment
C0206427
rod photoreceptor