What Are the Different Types of Nerve Tissue?

Nervous tissue is composed of nerve cells and glial cells, which are both cells with protrusions. Nerve cells are the structural and functional units of the nervous system, also known as neurons. The number of neurons is huge, and they have the ability to receive stimuli, conduct impulses, and integrate information. Some neurons also have endocrine functions.

Nervous tissue

Nervous tissue is composed of nerve cells and glial cells, which are both cells with protrusions. Nerve cells are the structural and functional units of the nervous system, also known as neurons. The number of neurons is huge, and they have the ability to receive stimuli, conduct impulses, and integrate information. Some neurons also have endocrine functions.

Chinese name

Nervous tissue

Foreign name

Nerve tissue

Make up

Neurons (ie nerve cells) and glial

Neuron function

Receive stimulation and conduct excitement

Glial action

Support, protection and nutrition

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Nerve tissue is highly differentiated

Nerve cells (nerve cells) are the main components of neural tissue. They are highly differentiated cells with a large number.

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Under the light microscope, most

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Myelinated nerve fiber

Myelinated nerve fibers consist of axons (or dendrites), myelin sheaths, and nerve membranes. Myelin sheath and neurolemma are sheathed around the axon. There is no myelin sheath at the beginning of the axon, this part is called the axon part far from the initial segment of the initial segment. The axonal membrane is exposed, and membrane potential changes can occur. This part is called the node of nerve fiber, also known as Ranvier node. A section between two adjacent nodes, called an internode, is about 0.5 to 1 mm long. It consists of a myelin sheath formed by a Schwann cell and the surrounding nerve membrane. The nucleus of Schwann cells is oblong and located in a small amount of cytoplasm at the edge of the myelin sheath. Myelin is mainly composed of lipids and proteins. It is called myelin. In conventional staining specimens, the lipids in myelin are dissolved. Only the remaining proteins are reticulated. neurokeratin network). The myelin sheath was black in osmotic acid-impregnated specimens, and several funnel-shaped oblique fissures were also seen, which were called incisure of myelin or Schmidt-Lanterman incisure. Under the electron microscope, the myelin sheaths are arranged in concentric circular layers of light and dark. Myelin sheath has protective and insulating effects, which can prevent the spread of nerve impulses. The nerve impulse conduction of myelinated nerve fibers is a jump conduction from one Lang Fei knot to an adjacent Lang Fei knot. With long nerve fibers, the axons are thick and the myelin sheath is thick. The nodular body is also long and has a fast conduction speed. On the contrary, the conduction speed is slow. Most of the brain and spinal nerves belong to myelinated nerve fibers. Myelin sheaths of myelinated nerve fibers in the central nervous system are formed by oligodendrocytes. Several protrusions of an oligodendrocyte can enclose several axons to form a myelin sheath. Its Langfei knot is wide, without myelin notch, and its cell body is located between nerve fibers.

Myelinated nerve fiber

Nonmyelinated nerve fiber (nonmyelinated nervefiber) consists of thin axons and Schwann cells, without myelin sheath and without fly knots. Under electron microscope, a Schwann cell with different depths can be seen to wrap 5 to 15 axons of varying thickness. The impulse conduction of myelinated nerve fibers is continuous conduction along the axon, and its conduction speed is much slower than that of myelinated nerve fibers. The postganglionic fibers and part of the sensory nerve fibers of the autonomic nerve belong to myelinated nerve fibers.