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Fig. 3. Rhabdomere volumes of receptor cells near the center of the retina. (A)
Light micrograph of longitudinal section showing two retinulae. bm, basement
membrane; ne, nuclei of elongate photoreceptors; np, nucleus of small proximal
receptor; r, rhabdom; t, tracheoles; te, tracheole ends. (B) Rhabdomere
volumes, calculated from 21 virtual sections (see Materials and methods and
Fig. 1A) of photoreceptors in
relation to depth of retina. Each rectangle represents a virtual section: its
vertical side represents the section thickness; the horizontal side represents
the area of the rhabdomere. The calculated rhabdomere volume for each cell
type is indicated.