How will you differentiate the central nervous system CNS and the peripheral nervous system PNS in terms of thier functions?
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The nervous system has two main parts:
The nervous system transmits signals between the brain and the rest of the body, including internal organs. In this way, the nervous system’s activity controls the ability to move, breathe, see, think, and more.1 The basic unit of the nervous system is a nerve cell, or neuron. The human brain contains about 100 billion neurons. A neuron has a cell body, which includes the cell nucleus, and special extensions called axons (pronounced AK-sonz) and dendrites (pronounced DEN-drahytz). Bundles of axons, called nerves, are found throughout the body. Axons and dendrites allow neurons to communicate, even across long distances. Different types of neurons control or perform different activities. For instance, motor neurons transmit messages from the brain to the muscles to generate movement. Sensory neurons detect light, sound, odor, taste, pressure, and heat and send messages about those things to the brain. Other parts of the nervous system control involuntary processes. These include keeping a regular heartbeat, releasing hormones like adrenaline, opening the pupil in response to light, and regulating the digestive system. When a neuron sends a message to another neuron, it sends an electrical signal down the length of its axon. At the end of the axon, the electrical signal changes to a chemical signal. The axon then releases the chemical signal with chemical messengers called neurotransmitters (pronounced noor-oh-TRANS-mit-erz) into the synapse (pronounced SIN-aps)—the space between the end of an axon and the tip of a dendrite from another neuron. The neurotransmitters move the signal through the synapse to the neighboring dendrite, which converts the chemical signal back into an electrical signal. The electrical signal then travels through the neuron and goes through the same conversion processes as it moves to neighboring neurons. The nervous system also includes non-neuron cells, called glia (pronounced GLEE-uh). Glia perform many important functions that keep the nervous system working properly. For example, glia:
The brain is made up of many networks of communicating neurons and glia. These networks allow different parts of the brain to “talk” to each other and work together to control body functions, emotions, thinking, behavior, and other activities.1,2,3 CitationsOpen Citations
Our nervous system is divided in two components: the central nervous system (CNS), which includes the brain and spinal cord, and the peripheral nervous system (PNS), which encompasses nerves outside the brain and spinal cord. These two components cooperate at all times to ensure our lively functions: we are nothing without our nervous system! Unlike the brain and the spinal cord of the central nervous system that are protected by the vertebrae and the skull, the nerves and cells of the peripheral nervous system are not enclosed by bones, and therefore are more susceptible to trauma. If we consider the entire nervous system as an electric grid, the central nervous system would represent the powerhouse, whereas the peripheral nervous system would represent long cables that connect the powerhouse to the outlying cities (limbs, glands and organs) to bring them electricity and send information back about their status.  Image credit: Alessandra Donato Basically, signals from the brain and spinal cord are relayed to the periphery by motor nerves, to tell the body to move or to conduct resting functions (like breathing, salivating and digesting), for example. The peripheral nervous system sends back the status report to the brain by relaying information via sensory nerves (see above image). As with the central nervous system, the basic cell units of the peripheral central nervous system are neurons. Each neuron has a long process, known as the axon, which transmits the electrochemical signals through which neurons communicate. Axons of the peripheral nervous system run together in bundles called fibres, and multiple fibres form the nerve, the cable of the electric circuit. The nerves, which also contain connective tissue and blood vessels, reach out to the muscles, glands and organs in the entire body Nerves of the peripheral nervous system are classified based on the types of neurons they contain - sensory, motor or mixed nerves (if they contain both sensory and motor neurons), as well as the direction of information flow – towards or away from the brain. The afferent nerves, from the Latin "afferre" that means "to bring towards", contain neurons that bring information to the central nervous system. In this case, the afferent are sensory neurons, which have the role of receiving a sensory input – hearing, vision, smell, taste and touch - and pass the signal to the CNS to encode the appropriate sensation. The afferent neurons have also another important subconscious function. In this case, the peripheral nervous system brings information to the central nervous system about the inner state of the organs (homeostasis), providing feedback on their conditions, without the need for us to be consciously aware. For example, afferent nerves communicate to the brain the level of energy intake of various organs. The efferent nerves, from the Latin "efferre" that means "to bring away from", contain efferent neurons that transmit the signals originating in the central nervous system to the organs and muscles, and put into action the orders from the brain. For example, motor neurons (efferent neurons) contact the skeletal muscles to execute the voluntary movement of raising your arm and wiggling your hand about. Peripheral nervous system nerves often extend a great length from the central nervous system to reach the periphery of the body. The longest nerve in the human body, the sciatic nerve, originates around the lumbar region of the spine and its branches reach until the tip of the toes, measuring a meter or more in an average adult. Importantly, injuries can occur at any point in peripheral nerves and could break the connection between the "powerhouse" and its "cities", resulting in a loss of function of the parts of the body that nerves reach into. So, it of great interest for scientists to understand how the nerves, or even how the axonal structure within the nerves, are protected from the constant mechanical stresses exerted on them. Work in this area of biology is carried out by Dr. Sean Coakley, in the laboratory of Prof Massimo Hilliard. The peripheral nervous system can be divided into somatic, autonomic and enteric nervous systems, determined by the function of the parts of the body they connect to. Author: Alessandra Donato from the Hilliard Lab How will you differentiate the central nervous system CNS and the peripheral nervous system PNS in terms of their funtions?The central nervous system (CNS) includes the brain and spinal cord, while the peripheral nervous system includes all of the nerves that branch out from the brain and spinal cord and extend to other parts of the body, including muscles and organs.
What is the main difference between the central nervous system CNS and the peripheral nervous system PNS )? Quizlet?What is the difference between the central and peripheral nervous system? The CNS is responsible for integrating, processing, and coordinating sensory input and motor output. The PNS provides sensory information to the CNS and carries motor commands from the CNS to peripheral tissues and system.
What is difference between central nervous system and peripheral nervous system?The central nervous system comprises the brain and spinal cord. The peripheral nervous system includes all peripheral nerves.
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