ニューロン | 定義、構造、種類、機能

Neuron | Definition, Structure, Types, & Functions | Britannica Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos neuron Introduction & Top Questions References & Edit History Quick Facts & Related Topics Images & Videos Related Questions What is the primary function of a neuron? What are the main parts of a typical neuron? How do neurons communicate with each other? What role do nerves play in the body? How was oxytocin discovered? Contents CITE verified Cite While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions. Select Citation Style MLA APA Chicago Manual of Style Copy Citation Share Share Share to social media Facebook X URL https://www.britannica.com/science/neuron Feedback External Websites Feedback Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login). Feedback Type Select a type (Required) Factual Correction Spelling/Grammar Correction Link Correction Additional Information Other Your Feedback Submit Feedback Thank you for your feedback Our editors will review what you’ve submitted and determine whether to revise the article. External Websites National Institute of Neurological Disorders and Stroke - Brain Basics: The Life and Death of a Neuron Verywell Mind - Neurons and Their Role in the Nervous System University of Queensland - Queensland Brain Institute - What is a neuron? National Library of Medicine - Neuroanatomy, Neurons BCcampus Open Publishing - Introduction to Psychology � The Neuron is the Building Block of the Nervous System Healthline - An Easy Guide to Neuron Anatomy with Diagrams Simply Psychology - An Easy Guide To Neuron Anatomy With Diagrams Neurons - Biology LibreTexts Michigan State University Libraries - Foundations of Neuroscience - The Neuron Neuron The fundamental cell of the nervous system is the neuron. Neurons in a human brain are shown here. (more) neuron anatomy Ask Anything Homework Help Also known as: nerve cell, neurone Written and fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors Last updated May 1, 2026 • History Britannica AI Ask Anything Table of Contents Table of Contents Ask Anything Top Questions What is the primary function of a neuron? The primary function of a neuron is to receive, process, and transmit information throughout the body. Neurons do this by generating electrical signals and passing them to other cells—such as other neurons or muscle cells—through specialized connections. This communication allows the nervous system to coordinate activities such as movement, sensation, thought, and regulation of internal functions. What are the main parts of a typical neuron? A typical neuron consists of three main parts: the cell body (soma), dendrites, and an axon . The cell body contains the nucleus and serves as the control center, processing incoming information. Dendrites are branching extensions that receive signals from other neurons and carry them toward the cell body, while the axon is a long fiber that transmits electrical impulses away from the cell body to other cells. How do neurons communicate with each other? Neurons communicate with each other through specialized junctions known as synapses , where signals are passed using both electrical and chemical processes. An electrical impulse travels down the axon of a neuron, and, when it reaches the synapse, it triggers the release of chemical messengers called neurotransmitters . These molecules cross a small gap between neurons and bind to receptors on the next cell, generating a new electrical signal. This process allows information to move rapidly through neural networks, enabling functions such as sensation, movement, and thought. What are the different types of neurons based on function? Neurons are classified as sensory neurons, motor neurons, or interneurons. Sensory neurons carry information to the central nervous system , while motor neurons transmit signals to effectors. Interneurons occur primarily within the brain and spinal cord and serve to connect sensory and motor neurons. What role do nerves play in the body? Nerves serve as communication pathways, carrying signals between the central nervous system (the brain and spinal cord) and the rest of the body. They are made up of bundles of neuron fibers (axons) that transmit electrical impulses. Through these signals, nerves allow the body to sense the environment, control movement, and regulate internal functions. News • For the first time, scientists pinpoint the brain cells behind depression • Apr. 28, 2026, 9:10 AM ET (ScienceDaily) ... (Show more) New tool can see how different brain cell types work together • Apr. 22, 2026, 7:00 PM ET (Medical Xpress) Show less neuron , basic cell of the nervous system in vertebrates and most invertebrates, appearing in organisms as simple as cnidarians such as corals and jellyfish and becoming highly specialized in more complex animals. Neurons are responsible for receiving, processing, and transmitting information through electrical and chemical signals, enabling functions ranging from basic reflexes to complex thought. The structure of a neuron A typical neuron consists of a cell body (soma) and two types of extensions: dendrites and an axon. (more) A typical neuron consists of a cell body (soma), which contains the nucleus and maintains cellular function, and two types of extensions: dendrites and an axon . Dendrites are usually numerous, branching fibers that receive incoming signals from other neurons and carry them toward the cell body. In contrast, the axon—typically a single, elongated projection—conducts impulses away from the cell body to other neurons, muscles, or glands. In many vertebrates axons are wrapped in a fatty insulating layer known as myelin , which speeds the transmission of nerve impulses. Axons can vary greatly in length; in large animals some extend several feet, such as those connecting the spinal cord to the limbs. Neurons communicate at specialized junctions called synapses , where electrical signals trigger the release of chemical messengers known as neurotransmitters. These chemicals cross a small gap and bind to receptors on the next cell, allowing signals to pass through complex neural networks. More From Britannica nervous system: The neuron Neurons are often classified by function. Sensory neurons carry information from receptors—such as those in the eyes , ears , or skin—to the central nervous system ( spinal cord or brain ). Motor neurons transmit signals from the central nervous system to effectors, such as muscles or glands, producing movement or secretion . Interneurons, found primarily within the brain and spinal cord, connect neurons to one another and play a key role in processing and integrating information. Also called: nerve cell (Show more) Key People: Paul Alfred Weiss Rudolf Jaenisch Fred H. Gage John J. Hopfield Thomas C. Südhof (Show more) Related Topics: neuroplasticity neural oscillation mirror neuron sensory neuron neurotransmitter (Show more) On the Web: Michigan State University Libraries - Foundations of Neuroscience - The Neuron (Apr. 23, 2026) (Show more) See all related content Bundles of neuron fibers, particularly axons, are grouped together by connective tissue to form nerves, which act as communication pathways throughout the body. Through these structures, neurons enable organisms to sense their environment , coordinate responses, and maintain internal balance, making them essential to nearly all aspects of animal life. The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Kara Rogers .