Consider a simple retina in which there are two photoreceptors, Rod A and Rod B,
ID: 3506994 • Letter: C
Question
Consider a simple retina in which there are two photoreceptors, Rod A and Rod B, connected by a single horizontal cell. Rod A projects to a bipolar cell, which in turn, projects to a ganglion cell. Assume there are excitatory connections between A and the bipolar cell, and excitatory connections between the bipolar cell and ganglion cell. For the system described answer the following questions: (a) We shine a light on Rod B while leaving Rod A in the dark. What activity will this cause in the bipolar cell described? Explain
(i) No effect (ii) Excite (iii) Inhibit
(b) The receptive field property of the ganglion cell described above is: (1) On-center (ii) Off-center
Explanation / Answer
In dark the bipolar cells are excited and maintain the hyperpolarization state but as the light falls on rod B cells it inhibits the cell and causes depolarization of the cells .As the light from rod B cells passes to rod A cells it will also inhibit it.
Ans (b) As the cells receive no light the bipolar cells are in ON hypolarized state but as the cells receive light it makes the bipolar cell in OFF state causes depolarization of the cells .