Functional Organization of the Retina of the Lemon Shark (Negaprion Brevirostris, Poey): An Anatomical and Electrophysiological Approach.
Technical rept. 1979-1980,
ROSENSTIEL SCHOOL OF MARINE AND ATMOSPHERIC SCIENCE MIAMI FLA
Pagination or Media Count:
The retina of the lemon shark Negaprion brevirostris was studied by both anatomical electrophysiological techniques. Light and electron microscopy reveal the normal complement of retinal cells found in other vertebrate retinas. The finding of both rod and cone photoreceptor cells was confirmed with the use of the electron microscopic. The interplexiform cell, was described for the first time in an elasmobranch. Action potentials recorded from the ganglion cells revealed three types of responses ON, OFF and ON-OFF. The ON center cells inputs had inputs from both rods and cones. Two classes of OFF center cells were found. One class had input only from one cone type while the second class had input from both rods and cone. The on component of the ON-OFF units had both rod and cone inputs, while the off component, as with the OFF center units were composed of two classes of units, those with just cone input and those with both rod and cone input. Author
- Anatomy and Physiology