Nervous tissue

Your body has a special way to talk.

Tiny parts send messages to your brain. These parts help you move and feel. They help you stay healthy.

Small cells send these messages. They use tiny signals to talk. These signals move from one cell to the next.

Other cells help the tiny messengers. They give them food. They also help the signals move fast.

Some parts have a special coating. This coating helps the messages zip along. It works like a fast road.

These parts work in your brain and your body. They help you think and move. It is a busy system!

Your body uses nervous tissue to send messages. This tissue is the main part of your nervous system. The system has two main parts. The central nervous system includes your brain and spinal cord. The peripheral nervous system includes the nerves in your body.

Two types of cells make up this tissue. The first type are neurons. These are nerve cells that send signals. They have a large cell body. They also have thin parts called dendrites. Dendrites receive signals from other cells. Neurons also have a long part called an axon. The axon carries the signal away to the next cell.

The second type are neuroglia. These are helper cells. They are smaller than neurons. They give food to the neurons. They also help signals move fast. Some neuroglia make a coating called myelin. This coating works like insulation on a wire. It helps the signal zip along the axon.

Nervous tissue helps you do many things. It helps you feel things. It helps you move your muscles. It even helps you think!

Nervous tissue is the main part of your nervous system. This tissue helps your body stay in control of its many jobs. The nervous system has two big parts. The first is the central nervous system, which includes your brain and spinal cord. The second is the peripheral nervous system, which is made of many branching nerves.

This tissue allows you to feel things and move your muscles. It also helps with mental activity and keeps your body balanced.

This tissue works by sending signals called action potentials. Neurons are the special cells that send these signals. A neuron has a large cell body called a soma. It also has thin parts called dendrites that receive signals. To send a signal, the neuron uses a long stem called an axon. The signal travels down the axon to the axon terminal.

At the end, it crosses a tiny gap called a synaptic cleft. The signal then moves to the next neuron using chemicals called neurotransmitters.

Neurons are not all the same. They can be grouped by how they work or how they look. Sensory neurons carry information from your body to your brain. Motor neurons carry signals from your brain to your muscles or glands. Interneurons stay in one local area to connect other neurons. Some neurons have three or more parts called multipolar neurons. Other types, like bipolar neurons, only have two parts.

Helper cells called neuroglia make this system work well. Neuroglia are smaller than neurons and provide many types of support. In the central nervous system, astrocytes are the most common type. Microglial cells act like a tiny immune system for your brain. Oligodendrocytes make a coating called myelin to help signals travel fast.

In the peripheral nervous system, Schwann cells do a similar job. They also help form the myelin coating for those nerves. Other helpers like satellite glial cells line the surface of cell bodies.

Nervous tissue is organized into different areas. In the central nervous system, you will find grey matter and white matter. Grey matter contains cell bodies and helps process information. White matter contains many myelinated axons that connect different areas.

In your limbs, nerves have three layers of protection. The endoneurium wraps each axon in a thin layer. The perineurium wraps bundles of axons together. Finally, the epineurium is the thick outer layer of the nerve. This structure is like a protected path for your body's messages.

Nervous tissue, also called neural tissue, is the primary component of the nervous system. This specialized tissue allows the body to regulate and control various functions and activities. The nervous system is divided into two main parts. The central nervous system (CNS) includes the brain and the spinal cord. The peripheral nervous system (PNS) consists of branching peripheral nerves.

Nervous tissue is essential for sensory input, integration, and the control of muscles and glands. It also maintains homeostasis and supports mental activity throughout the body.

The tissue functions as a communication network by conducting electrical signals. These signals are known as action potentials. The process begins when a neuron receives an electrochemical signal called a neurotransmitter. This happens at the dendrites, which are thin, branching projections on the cell. The signal creates a change in voltage across the cell membrane. This change travels through the soma, or cell body, and moves down the axon. The axon is a long, stem-like projection that carries the action potential away from the cell body.

When the action potential reaches the end of the axon, it hits the axon terminal. This terminal is separated from the next neuron by a tiny gap called a synaptic cleft. To bridge this gap, the neuron releases neurotransmitters across the synapse. These chemicals bind to receptors on the next neuron to continue the impulse. This step-by-step chain allows messages to move rapidly through the body. The speed of these messages can be increased by a lipid-based insulation called myelin.

Neurons are classified in two ways: by their function and by their structure. Functionally, sensory neurons, or afferent neurons, relay information from the PNS to the CNS. Motor neurons, or efferent neurons, carry action potentials from the CNS to muscles and glands. Interneurons form connections between other neurons within a local area. Structurally, multipolar neurons have three or more processes and are common in the CNS. Bipolar neurons have only two processes: one dendrite and one axon. Pseudounipolar neurons have a single process that splits into two branches. There are also unipolar brush cells, which are excitatory interneurons found in the cerebellum.

Neuroglia, or glial cells, are non-neural cells that support the neurons. They are smaller than neurons and perform many crucial tasks. In the CNS, astrocytes are the most abundant cell type and are vital for a healthy system. Microglial cells are the smallest neuroglia and act as the primary immune system for the CNS. Oligodendrocytes in the CNS form myelin sheaths to increase the speed of action potentials. In the PNS, Schwann cells perform a similar role by maintaining axons and forming myelin. Other types include satellite glial cells, which line neuron cell bodies in ganglia, and enteric glia found in the gastrointestinal tract.

Nervous tissue is organized into specific types depending on its location. In the CNS, there is grey matter and white matter. Grey matter contains cell bodies, dendrites, and unmyelinated axons, making it important for information processing. White matter consists of myelinated axons and oligodendrocytes, which facilitate impulses between grey matter areas. In the PNS, ganglion tissue contains cell bodies and dendrites to act as relay points. Nerves in the PNS are bundles of axons wrapped in protective connective tissue.

Each nerve in the PNS is protected by three distinct layers of connective tissue. The innermost layer is the endoneurium, a thin, delicate sheath surrounding each individual axon. The next layer is the perineurium, which encloses bundles of axons called fascicles. The perineurium has seven or eight concentric layers and prevents large molecules from entering the fascicle. The outermost layer is the epineurium, which is a dense layer of connective tissue. These layers work together to provide structural support and protection for the nerve fibers.

Understanding nervous tissue is also important for medicine because of various tumors, or neoplasms. Gliomas are tumors that arise from glial cells. There are many specific types of these, such as astrocytoma, oligodendroglioma, and medulloblastoma. Other tumors can affect the nerve sheaths, including neurofibroma and Schwannoma. Because nervous tissue controls so many vital body systems, these growths can significantly impact how the body functions.