basic structure of neuron

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Basic Structure of Neuron Function of Dendrites . In order for neurons to become active, they must receive action potentials or other stimuli. Dendrites are the structures on the neuron that receive electrical messages. These messages come in two basic forms: excitatory and inhibitory. The Cell body (soma) is the factory of the neuron. It produces all the proteins for the dendrites, axons and synaptic terminals and contains specialized organelles such as the mitochondria, Golgi apparatus, endoplasmic reticulum, secretory granules, ribosomes and polysomes to provide energy and make the parts, as well as a production line to assemble the parts into completed products. The action potential travels from one location in the cell to another, but ion flow across the membrane occurs only at the nodes of Ranvier . As a result, the action potential signal jumps along the axon, from node to node , rather than propagating smoothly, as they do in axons that lack a myelin sheath. Neurotransmitters are packaged into synaptic vesicles that cluster beneath the axon terminal membrane on the presynaptic side of a synapse. The axonal terminals are specialized to release the electrical impulse of the presynaptic cell.

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Page 1: Basic structure of neuron

Basic Structure of Neuron

Function of Dendrites. In order for neurons to become active, they must receive action potentials or other stimuli. Dendrites are the structures on the neuron that receive electrical messages. These messages come in two basic forms: excitatory and inhibitory.

The Cell body (soma) is the factory of the neuron. It produces all the proteins for the dendrites, axons and synaptic terminals and contains specialized organelles such as the mitochondria, Golgi apparatus, endoplasmic reticulum, secretory granules, ribosomes and polysomes to provide energy and make the parts, as well as a production line to assemble the parts into completed products.

The action potential

travels from one location in the cell to another, but ion flow across the membrane occurs only at the nodes of Ranvier. As a result, the action potential signal jumps along the axon, from node to node, rather than propagating smoothly, as they do in axons that lack a myelin sheath.

Neurotransmitters are packaged into synaptic vesicles that cluster beneath the axon terminal membrane on the presynaptic side of a synapse. The axonal terminals are specialized to release the electrical impulse of the presynaptic cell.

An axon (from Greek ἄξων áxōn, axis), is a long, slender projection of a nerve cell, or neuron, that typically conducts electrical impulses away from the neuron's cell body. Myelinated axons are known as nerve fibers. The function of the axon is to transmit inform

Function of the Nucleus.

Page 2: Basic structure of neuron

The nucleus is an organelle found in eukaryotic cells. Inside its fully-enclosed nuclear membrane, it contains the majority of the cell's genetic material. This material is organized as DNA molecules, along with a variety of proteins, to form chromosomes.ation to different neurons, muscles and glands.

Function[edit] The main purpose of a myelin layer (or sheath) is to increase the speed at which impulses propagate along the myelinated fiber. Along unmyelinated fibers, impulses move continuously as waves, but, in myelinated fibers, they hop or "propagate by saltatory conduction."

The major function of oligodendrocytes and Schwann cells is the formation of myelin. Myelin acts as an insulator of axonal segments and is a prerequisite for the high velocity of nerve conduction, of up to 200 m/second. The association of glial cells with axons is also found in invertebrates.

A neuron (/ˈnjʊərɒn/ NYEWR-on or /ˈnʊərɒn/ NEWR-on; also known as a neurone or nerve cell) is an electrically excitable cell that processes and transmits information through electrical and chemical signals. These signals between neurons occur via synapses, specialized connections with other cells.

In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron.

Physiology Something that can elicit or evoke a physiological response in a cell, a tissue, or an organism. A stimulus can be internal or external. Sense organs, such as the ear, and sensory receptors, such as those in the skin, are sensitive to external stimuli such as sound and touch.

Neurotransmitters are endogenous chemicals that enable neurotransmission. They transmit signals across a chemical synapse, such as in a neuromuscular junction, from one neuron to another "target" neuron, muscle cell, or gland cell.