Retina bipolar cell it, either through a metabotropic (ON) or ionotropic (OFF) receptor. However, the mechanism for producing the monochromatic surround of the same receptive field is under investigation. While it is known that an important cell in the process is the horizontal cell, the exact sequence of receptors and molecules is unknown. Retina bipolar cell As a part of the retina, bipolar cells exist between photoreceptors (rod cells and cone cells) and ganglion cells. They act, directly or indirectly, to transmit signals from the photoreceptors to the ganglion cells. Bipolar cells are so-named as they have a central body from which two
Three-spined stickleback then a stickleback's condition-factor (i.e. its ability to flee) determines how closely it approaches the predator rather than the stickleback's size. Both the strategy and reaction to different-sized partners seem to be dependent on whether the partner cooperates or defects. Sticklebacks have four colour photoreceptor cells in their retina, making them potentially tetrachromatic. They are capable of perceiving ultraviolet wavelengths of light invisible to the human eye and use such wavelengths in their normal behavioural repertoire. The three-spined stickleback is a known intermediate host for the hermaphroditic parasite "Schistocephalus solidus", a tapeworm of fish and fish-eating birds. Three-spined sticklebacks have