Nervous system diagram

Learning Objectives By the end of this section, you will be able to: • Identify the anatomical and functional divisions of the nervous system • Relate the functional and structural differences between gray matter and white matter structures of the nervous system to the structure of neurons • List the basic functions of the nervous system The picture you have in your mind of the nervous system probably includes the brain, the nervous tissue contained within the cranium, and the spinal cord, the extension of nervous tissue within the vertebral column. That suggests it is made of two organs—and you may not even think of the spinal cord as an organ—but the nervous system is a very complex structure. Within the brain, many different and separate regions are responsible for many different and separate functions. It is as if the nervous system is composed of many organs that all look similar and can only be differentiated using tools such as the microscope or electrophysiology. In comparison, it is easy to see that the stomach is different than the esophagus or the liver, so you can imagine the digestive system as a collection of specific organs. The Central and Peripheral Nervous Systems The nervous system can be divided into two major regions: the central and peripheral nervous systems. The central nervous system (CNS) is the brain and spinal cord, and the peripheral nervous system (PNS) is everything else ( Figure 12.2 Central and Peripheral Nervous System The structures o...

The nervous system, essentially the body’s electrical wiring, is a complex collection of nerves and specialized cells known as neurons that transmit signals between different parts of the body. Neurons signal to other cells through fibers called axons. Chemicals called neurotransmitters are released at gaps called synapses. These communications take only a fraction of a millisecond. Sensory neurons respond to stimuli such as light and sound. Motor neurons carry activation signals to muscles and glands. Neurons are supported and fed by glial cells. “Glial” derives from the Greek word for “glue.” Vertebrates, animals with backbones and spinal columns, have central and peripheral nervous systems. The Central Nervous System is the integration and command center of the body. It consists of the brain, spinal cord and the retinas of the eyes. The Peripheral Nervous System consists of sensory neurons, ganglia (clusters of neurons) and nerves that connect the central nervous system to arms, hands, legs and feet. The Cranial Nervous System nerves connect the brain to the eyes, mouth, ears and other parts of the head. The Autonomic Nervous System nerves connect the central nervous system to the lungs, heart, stomach, intestines, bladder and sex organs. The branch of medicine that studies the nervous system is called neurology. Doctors who treat the nervous system are neurologists. Ross Toro is a contributing infographic artist for Live Science. He specializes in explanatory graphics ...

Nervous systems are of two general types, diffuse and centralized. In the diffuse type of system, found in lower This article begins with a discussion of the general features of nervous systems—that is, their function of responding to stimuli and the rather uniform electrochemical processes by which they generate a response. Following that is a discussion of the various types of nervous systems, from the simplest to the most complex. Get a Britannica Premium subscription and gain access to exclusive content. controllers in a stimulus-response system. Directional responses of movement are known as In nervous system. A nervous system can be defined as an organized group of cells, called neurons, specialized for the conduction of an impulse—an excited state—from a Organisms that possess a nervous system are capable of much more complex behaviour than are organisms that do not. The nervous system, specialized for the conduction of impulses, allows rapid responses to environmental stimuli. Many responses mediated by the nervous system are directed toward preserving the status quo, or Intracellular systems All living cells have the property of irritability, or responsiveness to environmental stimuli, which can affect the cell in different ways, producing, for example, electrical, chemical, or mechanical changes. These changes are expressed as a response, which may be the release of secretory products by

Your ability to perceive your surroundings – to see, hear, and smell what’s around you – depends on your nervous system. So does your ability to recognize where you are and to remember if you’ve been there before. In fact, your very capacity to wonder how you know where you are depends on your nervous system! If your perceptions indicate danger (“Oh no, the house is on fire!”), your ability to act on that information also depends on your nervous system. In addition to letting you consciously process the threat, your nervous system triggers involuntary responses, like an increase in heart rate and blood flow to your muscles, intended to help you cope with danger. All of these processes depend on the interconnected cells that make up your nervous system. Like the heart, lungs, and stomach, the nervous system is made up of specialized cells. These include nerve cells (or neurons) and glial cells (or glia). Neurons are the basic functional units of the nervous system, and they generate electrical signals called action potentials, which allow them to quickly transmit information over long distances. Glia are also essential to nervous system function, but they work mostly by supporting the neurons. The cell bodies of some PNS neurons, such as the motor neurons that control skeletal muscle (the type of muscle found in your arm or leg), are located in the CNS. These motor neurons have long extensions (axons) that run from the CNS all the way to the muscles they connect with (inner...

Your nervous system is your body’s command center. Originating from your brain, it controls your movements, thoughts and automatic responses to the world around you. It also controls other body systems and processes, such as digestion, breathing and sexual development (puberty). Diseases, accidents, toxins and the natural aging process can damage your nervous system. Overview What is the nervous system? Your nervous system guides almost everything you do, think, say or feel. It controls complicated processes like movement, thought and memory. It also plays an essential role in the things your body does without thinking, such as breathing, blushing and blinking. Your nervous system affects every aspect of your health, including your: • Thoughts, memory, learning, and feelings. • Movements, such as balance and coordination. • Senses, including how your brain interprets what you see, hear, taste, touch and feel. • Sleep, healing and aging. • Heartbeat and breathing patterns. • Response to stressful situations. • Digestion, as well as how hungry and thirsty you feel. • Body processes, such as puberty. This complex system is the command center for your body. It regulates your body’s systems and allows you to experience your environment. A vast network of nerves sends electrical signals to and from other cells, glands, and muscles all over your body. These nerves receive information from the world around you. Then the nerves interpret the information and control your response. I...

Human Nervous System Structure and Functions Explained With Diagrams Diagrams! They remind me of school textbooks which used to have plenty of them, providing a visual aid to understanding difficult subjects. This article explains the nervous system function and structure with the help of a human nervous system diagram and gives you that erstwhile 'textbook feel'. Read on. Diagrams! They remind me of school textbooks which used to have plenty of them, providing a visual aid to understanding difficult subjects. This article explains the nervous system function and structure with the help of a human nervous system diagram and gives you that erstwhile ‘textbook feel’. Read on. The thought of diagrams brought back memories of school days; the scent of those textbooks; the sight of the classroom and my teacher’s voice that said, “C’mon class, open your science books, page 41, chapter 3, Human Body Systems”. Studying human anatomy became interesting, thanks to her. She used to say, “The human body systems are the most accurately engineered machines that possess an intellect of their own. Look at the brain, for example; man will never be able to replicate its intricate design or recreate intelligence and emotion”. It was wonderful to pick up the intricacies of a seemingly boring subject like human anatomy from her. She was a person who looked at science through a philosopher’s eye. Reading this article will be like reading about the human nervous system from your science textbook...

Central nervous system anatomy The central nervous system (CNS) is a division of the The CNS consists of two organs which are continuous with each other; the brain and While analyzing the information and preparing adequate body responses, the parts of the brain and spinal cord communicate with each other via many This article will introduce you to the anatomy and functions of the central nervous system. Key facts about the central nervous system Definition and function The supreme command center of the body that receives, integrates, processes, and generates neural impulses that control all the bodily functions Parts Brain (cerebrum, cerebellum, brainstem, subcortical structures) Spinal cord Synonyms: Soma, Perikaryon The chief cells of the brain and spinal cord are the which is its micro-command center, and it has a gray color when observed microscopically. The neurons possess two or more neural processes that stem from the body and relay the neural information. The neural processes are divided into short ( The parts of neurons comprise what we call gray and white matter. The gray matter is made up of clusters of neuronal bodies, while the white matter is composed of their myelinated axons. The axons are not just randomly interwoven through the neural tissue, but rather are organized into bundles that connect certain parts of gray matter and carry the relevant impulses. In the CNS, these bundles are called pathways and tracts, while in the PNS they comprise nerves. The di...

The nervous system has two major parts: the central nervous system (CNS) and the peripheral nervous system (PNS). The central system is the primary command center for the body, and is comprised of the brain and spinal cord. The peripheral nervous system consists of a network of nerves that connects the rest of the body to the CNS. In most cases, the brain is the final destination point for information gathered by the rest of the nervous system. Once data arrives, the brain sorts and files it before sending out any necessary commands. The brain is divided into many different sections, including the cerebrum and brain stem. These parts handle pieces of the brain’s overall workload, including storing and retrieving memory and making body movements smooth. Although the brain is the control center, its job would not be possible without the spinal cord, which is the major conduit for information traveling between brain and body. Peripheral system nerves branch from either the brain stem or the spinal cord. Each nerve is connected to a particular area of the torso or limbs and is responsible for communication to and from those regions. The PNS can also be subdivided into smaller components: the somatic and autonomic systems. The somatic involves parts of the body a person can command at will, and the autonomic helps run involuntary functions such as pumping blood. Information conveyed through the nervous system moves along networks of cells called neurons. These neurons can only ...