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The pseudounipolar neuron's axon then splits into two branches. Sensory neurons with cell bodies in the dorsal root ganglia of the vertebrate spinal cord are pseudo-unipolar: one branch projects to the periphery (to sensory receptors in the skin, joints, and muscle), the other to the spinal cord.
The neurons comprising the dorsal root ganglion are of the pseudo-unipolar type, meaning they have a cell body (soma) with two branches that act as a single axon, often referred to as a distal process and a proximal process.
The axon primarily carries nerve signals away from the soma and carries some types of information back to it. Many neurons have only one axon, but this axon may—and usually will—undergo extensive branching, enabling communication with many target cells. The part of the axon where it emerges from the soma is called the axon hillock.
A neurite or neuronal process refers to any projection from the cell body of a neuron.This projection can be either an axon or a dendrite.The term is frequently used when speaking of immature or developing neurons, especially of cells in culture, because it can be difficult to tell axons from dendrites before differentiation is complete.
The axon hillock is the last site in the soma where membrane potentials propagated from synaptic inputs are summated before being transmitted to the axon. [2] For many years, it was believed that the axon hillock was the usual site of initiation of action potentials —the trigger zone .
There are four subdivisions of group A nerve fibers: alpha (α) Aα; beta (β) Aβ; , gamma (γ) Aγ, and delta (δ) Aδ. These subdivisions have different amounts of myelination and axon thickness and therefore transmit signals at different speeds. Larger diameter axons and more myelin insulation lead to faster signal propagation.
The RGC will then extend an axon in the retinal ganglion cell layer, which is directed by laminin contact. [19] The retraction of the apical process of the RGC is likely mediated by Slit–Robo signaling. [13] RGCs will grow along glial end feet positioned on the inner surface (side closest to the future vitreous humor).
Association fibers are axons (nerve fibers) that connect cortical areas within the same cerebral hemisphere. [1]In human neuroanatomy, axons within the brain, can be categorized on the basis of their course and connections as association fibers, projection fibers, and commissural fibers. [1]