Essay on ANS Nervous System

20.The part of the ANS that is responsible for reacting to stressful events and bodily arousal is called the  sympathetic division of the nervous system.

Among various types of organ systems, the nervous system is one of the most important one in human body. It is responsible for producing, controlling and guiding our thoughts and responses to the world around us according to James W. Pennebaker (2012). During embryological development, the cells that form nervous system are incredibly specialised and work complexly than the cells that form skin or other body parts. Neurosecretory cells are one of the examples of specialised nervous system cells that produce neurosecretions. Neurosecretions are hormones which carry information from sensor cells to target cells and they can be released directly into the bloodstream

The sympathetic nervous system is controlled by the hypothalamus and transmits signals down the spinal cord to the periphery through alpha and beta receptor sites. Alpha receptor stimulation induces smooth muscles contraction in blood vessels and bronchioles. Beta receptors respond with smooth muscle relaxation in blood vessels and bronchioles. Controls the “fight or flight” response which controls sweating, pupil dilations, and temperate regulation. Loss to the sympathetic nervous system can disrupt homeostasis. The parasympathetic nervous system carries signals to the organs in the abdomen, heart, lungs, and skin above the waist. The parasympathetic nerves attempt to control a rapidly increasing blood pressure by slowing heart rate, this may happen when the sympathetic nervous system is

There are two neurons that link the CNS to the effector organ namely the pre-ganglionic neuron with a cell body in the CNS and a post-ganglionic neuron with a cell body located in an autonomic ganglion. The adrenal medulla is an exception, with it being connected directly to the preganglionic neuron. The main neurotransmitters are acetylcholine (ACh) and adrenaline. Preganglionic neurons for both sympathetic and parasympathetic are cholinergic, Releasing ACh. The ACh released binds to nicotinic receptors on the post-ganglionic neuron. Post-ganglionic neurons are also cholinergic in the parasympathetic, releasing ACh. This ACh bind to muscarinic receptors in target organs. However, the sympathetic post-ganglionic neurons are noradrenergic, releasing

The limbic and olfactory systems (the amygdala, the hippocampus, and the olfactory cortex) help control eating and reproduction through the hypothalamus. The thermoreceptors and the osmoreceptors in the hypothalamus are receptors that help monitor temperature and ionic balance. The hypothalamus can control every endocrine gland in the body. The hypothalamus can alter blood pressure, body temperature, metabolism, and adrenaline levels. There are two outputs that the hypothalamus uses when it becomes aware of a problem. One of the outputs it uses is sending neural signals to the autonomic system. The hypothalamus sends signals to the medulla, where the parasympathetic vagal nuclei and cell groups that descend to the spinal cord are located, which help drive the autonomic system. When the hypothalamus gains admittance to these systems, it is able to control functions such as digestion, heart rate, sweating, and vasoconstriction (when blood vessels narrow, and consequently reduce the flow of blood or create high blood pressure). The other input the hypothalamus uses is sending endocrine signals, chemical signals sent through the blood stream, to the pituitary. Large cells from the hypothalamus send axons to the posterior pituitary, which in turn releases oxytocin and vasopressin into the bloodstream. More axons are also sent by smaller cells to the base of the pituitary. There the axons discharge releasing factors into the pituitary's capillary system. This

Parasympathetic Nervous System: Responsible for returning your body to its normal functioning by slowing down your heart rate, lowering your blood pressure, and increasing your digestive and eliminative processes.

Acute stress causes the arousal of the autonomic nervous system (ANS). The ANS comprises of the sympathetic nervous system (SNS) which prepares the individual for ‘fight or flight’ and the parasympathetic branch, which returns the individual to their original state of relaxation. Part of the SNS response is the sympathetic adrenal system (SAM), this system along with the SNS is collectively called the sympathomedullary pathway. The SNS is activated when the neurotransmitter noradrenaline is released and travels to the organs of the body preparing them for rapid action. Common responses to this would be increased heart rate, increased pupil size and metabolic changes such as a release of

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

When the sympathetic nervous system kicks into gear, the body speeds and tenses up, and, overall, becomes extremely alert. It then sends out impulses to glands and smooth muscles, while alerting the adrenal medulla to release the stress hormones, norepinephrine and epinephrine, into the bloodstream. At the same time, the hypothalamus releases the corticotropin-releasing factor (CRF)

In (a)-(e), a directional term is followed by elbow/wrist. In each case, choose the structures or locations. In each case, choose the structure or organ that matches

Not all processes in the body are voluntarily controlled and it is quite important to display automatic involuntarily controlled movements. The autonomic nervous system (ANS) controls the smooth muscles of internal organs allowing them to execute vital functions such as breathing and regulating the heartbeat in an organized and automatic fashion (Pastorino and Doyle-Portillo, 2017, pg. 59). The ANS and its complex neural network maintain homeostasis, and it can be further divided into two categories: the parasympathetic nervous system and the sympathetic nervous system.

Both systems usually perform on the same organ and produce the same action potentials, yet their functions are diverse and they compete with one another (Appendix 3). The sympathetic nervous system prepares the body for emergency situations while the parasympathetic nervous system maintains conserving functions when the body is at rest. Parasympathetic ganglia occur individually in the tissues and organs, however sympathetic ganglia occur on either side of spinal cord as two lateral chains. Preganglionic fibers of sympathetic nervous system arise from thoracic and lumbar segments of spinal cord, whereas that of parasympathetic nervous system arises from the midbrain and sacral segments of the spinal cord. Overall effect of sympathetic nervous

The sympathetic branch or ganglia of neurons comprising the sympathetic branch are interconnected so that they form a long chain on each side of the spinal cord. The sympathetic branch originates in the two middle portions of the spinal cord; the interconnections between the neurons allow the sympathetic branch to act as a unit. It is important because the sympathetic branch prepares the body to extend energy. As well as the effects show in the diagram below

First order neurons concern the initial nerve impulse from the receptor and transmission of the stimuli to the spinal cord. Interestingly, many of these neurons are psuedounipolar (2). They have two axons and a central cell body. The central bodies of these neurons are concentrated in the dorsal root ganglion, which is located in the dorsal root of a spinal nerve. This nodule allows for organization of the neurons, particularly the axons, which join to form neural fibers. The peripheral axons extend away the cell body and end where stimuli will be received. This is where the receptors are located (1).

T2 facial sweating can take T1 nerve to brachial plexus if can avoid Stellate ganglion.