Appendix 5—figure 1. R1-R6 photoreceptors’ rhabdomere sizes differ consistently.

(A) Electron micrographs of a characteristic wild-type (left) and hdc^JK910 (right) ommatidia. Each ommatidium contains the outer receptors, R1-R6, and the inner receptors, R7/R8, which can be identified by their rhabdomeres’ relative positions. Here R8s are not visible because these lie directly below R7s. Markedly, both wild-type and hdc^JK910 R1-R6 photoreceptor rhabdomere sizes vary systematically. (B) The mean rhabdomere sizes measured from 25 ommatidia from 10 flies. hdc^JK910 R1-R6 rhabdomere cross-sectional areas are smaller than those of the wild-type cells, but show similar proportional variations. Error bars show SEMs.