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Encyclopedia > Bipolar cell

As a part of the retina, the bipolar cell exists between photoreceptors (rod cells and cone cells) and ganglion cells. Human eye cross-sectional view. ... A photoreceptor is a specialized form of cell (specifically, neuron) that is capable of phototransduction. ... Normalised absoption spectra of human rod (R) and cone (S,M,L) cells. ... Normalised absorption spectra of human cone (S,M,L) and rod (R) cells Cone cells, or cones, are cells in the retina of the eye which only function in relatively bright light. ... A ganglion cell (or sometimes called a gangliocyte) is a type of neuron located in the retina that receives visual information from photoreceptors via various intermediate cells such as bipolar cells, amacrine cells, and horizontal cells. ...


Bipolar cells are so-named as they have a central body from which two sets of processes arise. At one end, they form(cranial nerve II). Bipolar cells effectively transfer information from rods and cones to ganglion cells.


They can be categorized into two different groups, ON and OFF, according to how they react to glutamate produced by photoreceptor cells. When light hits a photoreceptor cell, the photoreceptor hyperpolarises, and its glutamate production decreases. An ON-cell will react to this change by depolarizing. An OFF-cell will depolarize when glutamate production increases(when light power decreases). The interactions between bipolar cells and the horizontal cells create an extra layer of complexity - ON bipolar cells will depolarise to a stimulus that is in the centre of their receptive field, and hyperpolarise to a stimulus that is in the periphery of the receptive field. OFF bipolar cells show exactly the opposite behaviour. This mutually inhibitory centre-surround relationship increases the contrast of the retinal image by enhancing the edges of the object that is viewed. Glutamate is the anion of glutamic acid. ... Photoreceptor cells are contained in the retina and are responsible for transducing, or converting, light into signals that can be ultimately transmitted to the brain via the optic nerve. ...


The mechanism for producing the center of a bipolar cell's receptive field is well known: direct innervation of the photoreceptor above 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 as of yet unknown. Receptive fields are areas of the retina, producing a change in the firing of cells in the visual system. ... A photoreceptor is a specialized form of cell (specifically, neuron) that is capable of phototransduction. ... Metabotropic receptor is a transmembrane receptor, which starts some intracellular biochemical cascade after its activation by an agonistic ligand. ... ... Cells in culture, stained for keratin (red) and DNA (green). ... Horizontal cells are the laterally interconnecting neurons in the outer plexiform layer of the retina. ... In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. ... In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ...

Sensory system - Visual system - Eye - Retina - edit
Photoreceptor cells (Cone cellRod cell) → (Horizontal cell) → Bipolar cell → (Amacrine cell) → Ganglion cell

Giant retinal ganglion cells | Photosensitive ganglion cell (See also sense) A sensory system is a part of the nervous system that consists of sensory receptors, neural pathways, and those parts of the brain responsible for processing the information. ... The visual system is the part of the nervous system which allows organisms to see. ... This article or section does not cite its references or sources. ... Human eye cross-sectional view. ... Photoreceptor cells are contained in the retina and are responsible for transducing, or converting, light into signals that can be ultimately transmitted to the brain via the optic nerve. ... Normalised absorption spectra of human cone (S,M,L) and rod (R) cells Cone cells, or cones, are cells in the retina of the eye which only function in relatively bright light. ... Normalised absoption spectra of human rod (R) and cone (S,M,L) cells. ... Horizontal cells are the laterally interconnecting neurons in the outer plexiform layer of the retina. ... Amacrine cell Retinal cell interneuron interacting at the Inner Plexiform Layer (IPL), the second synaptic retinal layer where bipolar cells and ganglion cells synapse. ... A ganglion cell (or sometimes called a gangliocyte) is a type of neuron located in the retina that receives visual information from photoreceptors via various intermediate cells such as bipolar cells, amacrine cells, and horizontal cells. ... Giant retinal ganglion cells were discovered in the human and macaque retina by Dacey et al. ... This article needs to be cleaned up to conform to a higher standard of quality. ...


  Results from FactBites:
 
Retina (1327 words)
The neuropil layers are the outer plexiform layer and the inner plexiform layer.
The receptive fields of retinal ganglion cells comprise a central approximately circular area, where light has one effect of the firing of the cell, and an annular surround, where light has the opposite effect of the firing of the cell.
One response, from on cells, is to increase the rate of firing to increases in light intensity in the centre of the receptive field.
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