The Structure of the ANS System and the Effects it Has Shown to Have on Physiological and Behavioral Functions

What are the two divisions of the ANS? Where are the neurons for each division located, and what is the major function of each division?

Our nervous system is there to help to transfer the things our body feels and what we need. The nervous is broken up into two parts, the central nervous system (CNS), and the peripheral nervous system (PNS). The CNS controls the brain and the spinal cord, the PNS controls the nerves and the ganglia (a small mass of gray matter). Our body uses the spinal cord to send messages to the nerves so that it can control our organs and muscles.

The nervous system is a multiplexed body system that controls most other body systems directly or indirectly by sending and receiving signals through a complex system of nerves. As a whole, the nervous system can be broken down into the central nervous system (CNS) and peripheral nervous system (PNS). The CNS is composed of the brain and spinal cord while the PNS is composed of peripheral nerves that branch off of the spinal cord and continue to branch to reach the most distal points of the limbs. The PNS can be further broken down into the afferent and efferent division. The afferent division deals with information brought to the CNS from the nerve receptors. Furthermore, the afferent division breaks down into somatic sensory receptors whose

autonomic pathways is shown in Figure 1.2. Sympathetic preganglionic neurons have their cell bodies within the spinal cord (lateral gray horns) in thoracic and lumbar (T1 to L2) segments of the spinal cord, and for this reason they are called the thoracolumbar division. The cell bodies of the preganglionic neurons of the parasympathetic division have their cell bodies at the brainstem in the four pairs of cranial nerves: oculomotor (III), facial(VII), glossopharyngeal (IX) and vagus (X), and the sacral segments of the spinal cord, and for these reasons are known as craniosacral division. At least 75% of all parasympathetic preganglionic fibers travel in the vagus nerve (X) before synapsing with postganglionic fibers to innervate the effectors (the lungs, heart, liver stomach, spleen, pancreas, small and large intestine). Although they have different pathways, most of the effectors are dually innervated from both the sympathetic andparasympathetic division. For example, sympathethic nerve stimulation of the heart increases therate and strength of contraction, whereas parasympathetic stimulation decreases heart rate andstrength of contraction. The sympathetic impulses tend to stimulate activity and

The first communication system is the Nervous System (NS), which includes the Central Nervous System (CNS) and the Peripheral Nervous System (PNS). The CNS is comprised of the brain, spinal chords and nerves, and the PNS is comprised of sensory neurons, ganglia (clusters of nerves) and nerves that connect to one another and to the CNS. Sensory neurons act as receptors, and respond to physical stimuli such as light and sound, and send feedback to the CNS regarding the body’s surrounding environment which leads to, as previously mentioned, motor neurons in the CNS, or even in the ganglia of the PNS, transmitting the signals to the muscles and glands. This is how the receptors interact with the effectors via the CNS. In the PNS, there is a sub-system called the Autonomic Nervous System (ANS), which regulates glands, smooth muscle, heart rate etc, under subconscious control. The ANS has two ‘divisions’: the sympathetic division, which speeds up functions and can be asscociated with ‘emergency reactions’ to unfamiliar or extreme events, and the parasympathetic division, which slows down functions and is associated with automatic responses to day to day life. These two divisions of the ANS are essential to homeostais in that they allow for subconscious responses in relation to external stimuli. The ANS also bases its

The central nervous system controls most functions of the body and mind. The information obtained from the peripheral

CNS. The CNS acts as the control center of the body by providing its processing, memory,

An autonomic nerve pathway involves two nerve cells. One cell is located in the brain stem or spinal cord. It is connected by nerve fibers to the other cell, which is located in a cluster of nerve cells. Nerve fibers from these ganglia connect with internal organs. Most of the ganglia for the sympathetic division are located just outside the spinal cord on both sides of it. The ganglia for the parasympathetic division are located near or in the organs they connect with.

The ANS stands for the autonomic nervous system is the part of the peripheral nervous system. It controls the function of the body like heart rate, blood flow, digestion and breathing. It has been divided into two branches which are ‘sympathetic’ and a ‘parasympathetic’ branch. The two divisions work together and function opposite to each other. The sympathetic division prepares the body for the emergency or a stressful situation. It is also known as a fight or flight response. For example, if Jack was waiting for his bus and he had to show his ticket to get on the bus he checked his wallet he couldn’t find, his heart rate would rise up, his hands would sweat, and the hair stand on the end. He then checked his pocket and found his ticket,

The nervous system has three main functions: gathering sensory information from external stimuli, synthesizing that information, and responding to those stimuli. The CNS is mainly devoted to the "information synthesizing" function. During this step in the process, the brain and spinal cord decide on appropriate motor output, which is computed based on the type of sensory input. The CNS regulates everything from organ function to high-level thought to purposeful body movement. Thus, the CNS is commonly thought of as the control centre of the body.

Within the human anatomy, an intricate and complex network of specialised nerve fibres and neurons works in collaboration with the central nervous system and peripheral system, designed to carry out the various actions humans perform every day. The nervous system is also known as the master control unit of the human body, as it operates other major functions such as the circulatory and respiratory systems (Jakab, 2006). It is composed of the central nervous system (CNS) and the peripheral nervous system (PNS). The neurons established within the various sections of the nervous system, is structured with three main parts: a dendrite which is a cluster of branches that operates by receiving information from the

The sympathetic nervous system is more known by the conventional name of the main reaction,

The nervous system of Anniyas is a complicated network of nerve cells interlaced with one another and specialized cells performing one of the most complex functions in the bodies of Anniya. The nervous system serves as a network of communication to many organs of the body, and it also functions as a control system to maintain homeostasis of the Anniyas’ bodies. It controls numerous body activities through stimuli, hormones, and other methods. As the internal and external environment change, the nervous system can send impulses to various parts of the body to respond to stimuli and maintain homeostasis. In Anatomy and Physiology by Tortora & Derrickson, it is mentioned that the nervous system is separated into two divisions: “The central nervous system (CNS) which comprises the brain and spinal cord, and peripheral nervous system (PNS), which is made up of ganglia, sensory receptors, and enteric plexus which, carry nerve impulses to and from the body” (400). The Anniyas’ peripheral nervous system is also divided into three systems:

The nervous system of the body is the communication and control network it comprises of the central nervous system (CNS), peripheral nervous system (PNS) and the autonomic nervous system (ANS).The brain and the spinal cord comprise to form the CNS, this is the body’s main control centre. The PNS is a complex network of nerves branching across the whole body, 12 pairs of cranial nerves originate from the brain and 31 pairs of spinal nerves originate from the spinal cord. These nerves transmit information between the body and the brain via nerve impulses. The ANS shares nerve structures with both the CNS and PNS, it functions automatically with no conscious awareness to control the body’s basic functions like heart rate. In the PNS there are two divisions; afferent and efferent. The afferent division controls signals sent to the brain and the efferent division controls message from the brain to the body. Sensory inputs travel via the afferent division to signal the brain for processing, co-ordination and interpretation. The brain makes a suitable decision to the signal sent and

The organs of our body are controlled by many systems in order to function correctly and efficiently in order to survive within the environment we live in. These include the heart, stomach and intestines and other vital organs and body systems. All of the systems in our body are regulated by a part of the nervous system called the autonomic nervous system (ANS). The ANS is part of the peripheral nervous system and it controls many organs and muscles within the body. Rather bizarrely we are unable to determine or feel its presence in our bodies as it is working involuntary, as a reflexive manner. A common example of this involuntary action is best understood when