Human Body Systems and Their Functions - Essay Example

s Functions of the Central Nervous System The nervous system comprises of the spinal cord conduit, the brain,and multiple connections of neurons. Through this system, the body can have coordination of the internal body organs. Moreover, it can receive signals, interpret, and respond to external stimuli. The central nervous system serves as the core for processing any information of the nervous system. The primary function includes the reception, interpretation, and sending response from the entire body (Brodal, 2010:56-58). The brain and spinal cord have similar anatomical structures but play different functions. The brain serves as the central controlling organ of the body. It consists of three components that work in conjunction, although each plays a distinct role. The forebrain focuses on reception of signals, processing of sensory information, percept ion, production, and language understanding. Moreover, thinking occurs in this region. The forebrain has structures charged with motor function control and these include the thalamus and hypothalamus. This region also consists of the cerebrum, whose cortex hosts most of the information processing (Brodal, 2010:65-69). The midbrain has its unique functions as well. Being the link between the forebrain and hindbrain, the midbrain serves in producing responses for auditory and visual responses. Moreover, some motor functions occur in this region. On the other hand, the hindbrain is an extension from the spinal cord (Scott and Fong, 2009:137). It comprises of unique structures that aid in balance maintenance, and coordination of movement. These parts are the cerebellum and the Pons, ands are also critical in ensuring timely conduction of sensory signals. Moreover, the medulla oblongata found in the hindbrain maintains a balanced control of breathing, digestion, and heart rate. On the other hand, the spinal cord plays very essential roles that involve transmission of information sent from the body organs and external receptors. The spinal cord has a cylindrical structure with a bundle of numerous nervous fibers. The fibers have a connection with the brain that ensures that a relay of all the nervous messages to the brain (Scott and Fong, 2009:137). The spinal cord extends from the neck to the back, protected by a special column and consisting of both ascending and descending nervous tracts. Ascending tracts head to the brain with signals from all organ receptors, whereas the descending tracts carry the signal responses from the brain to body organs. The ascending nervous tracts usually relay sensory information to the brain while the descending tracts are responsible for delivering motor function information to the different body parts. As mentioned above, the nervous system also consists of neurons with each of the neurons forming the basic unit of the entire system. Three categories of neurons exist that differ in structure and function. Each of the units has a structure defined by the cell body, axons, and dendrites. The axons are responsible for carrying information away from the cell body while the dendrites perform the reverse action (Scott and Fong, 2009:139). Neurons have an interconnection system that allows a double-flow of information. Functions of the Autonomic Nervous System The autonomic nervous system holds the responsibility of maintaining a regulation of the visceral organs and the associated processes. Visceral processes ensure that all bodily functions take place at optimum conditions. The autonomous nervous system operates independently except for alterations brought about by emotions such as fear, distress, sexual excitement, and changes in the sleep cycles (Qu, 2009:12-16). This systems regulation surrounds the smooth and heart muscles and the glands. However, it also goes further to relay visceral information to the brain and complementary components of the system in order to trigger homeostatic processes. The system has two categories that complement each other in regulating homeostatic processes. The parasympathetic and sympathetic categories exhibit a linkage to the central nervous system although they have their neurons in different locations and function distinctly. Functions of the Endocrine Systems The endocrine system consists of glands charged with releasing different hormones. The endocrine system exerts chemical influence to the body through the release of chemical substances that trigger different processes (Burstein, 2009:20). These chemical substances enter the bloodstream after release. Through the bloodstream, the specific hormones eventually reach the target organ and initiate the desired change by attaching themselves to the hormone receptors (Nevid, 2009:42). Hormonal changes do not result as rapidly as nervous changes. The hypothalamus glands in the brains act as the link between the central nervous system and the endocrine system. The endocrine system releases numerous chemical substances in different levels depending on the desired change. These hormones have elaborate and specific effects on other physiological systems in the body (Burstein, 2009:7-8). Diagram showing the functioning of the endocrine system. Available from http://www.google.co.ke/imgres?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&channel=fflb&biw=1024&bih=609&tbm=isch&tbnid=k8R7kphLbmUfeM:&imgrefurl=http://library.thinkquest.org/07aug/01618/endocrine.html&docid=klzd2uqr9kdSaM&imgurl=http://library.thinkquest.org/07aug/01618/endocrinehormone.jpg&w=546&h=874&ei=lbEnUeavFobRkQXn9oD4Cw&zoom=1&ved=1t:3588,i:177&iact=rc&dur=301&sig=116218172592145167772&page=1&tbnh=186&tbnw=116&start=0&ndsp=16&tx=48&ty=56 Connection of the Central Nervous, Endocrine, and Autonomous Systems The three systems described above have a connection. Both the autonomous and endocrine system has a link to the brain, which is the centre for processing any type of information. For example, the hypothalamus glands in the brain relay messages to the brain involving its contribution to the action initiated by the hormones (Spiegel, 2003:101). On the other hand, both the sympathetic and parasympathetic autonomous systems have neural connections with the brain. Moreover, the autonomous system exerts a level of influence on the brain, and this translates to the contribution of the central nervous system to maintaining a balance in homeostatic processes. The connection existing between the three systems indicate that behavioral modifications and changes are the result of complex interactions (Spiegel, 2003:106). The complex interaction involves sending and receiving different signals from one system to the other. Diagram showing the connection between the central nervous system, endocrine and autonomous system Available from http://www.google.co.ke/imgres?hl=en&client=firefox-a&hs=Syx&sa=X&rls=org.mozilla:en-US:official&channel=fflb&biw=1024&bih=609&tbm=isch&tbnid=DKF5xeC0-EpsmM:&imgrefurl=http://www.sciencedirect.com/science/article/pii/S1357272598000946&docid=w8Oo2UQG2gb0GM&imgurl=http://ars.els-cdn.com/content/image/1-s2.0-S1357272598000946-gr2.jpg&w=722&h=504&ei=P60nUY6II4nfkAXY1YH4Cw&zoom=1&ved=1t:3588,i:114&iact=rc&dur=812&sig=116218172592145167772&page=1&tbnh=175&tbnw=236&start=0&ndsp=15&tx=133&ty=75 Localization of the Brain’s Functions Contrary to some organs like the liver that have most of their parts focusing on a similar task, the brain exhibits a high level of localization of its functions. Each part of the brain has its unique and distinct role that it plays in coordinating body physiology. Information send to the brain has a categorical form of organization, with beach category destined for a different location in the brain. After years of intense debate about localization, researchers realized that each part of the brain only specializes in a certain task different from the part in closet proximity to it (Riva, Njiokiktjien, & Benton, 2010:47). For example, the back edges of the frontal lobes handle all motor functions. This implies that the front edge of the same lobes performs an entirely different function (Clarke, Dewhurst, & Aminoff, 2006:1-2). Some regions of the brain act as association areas that do not have designated motor functions but are responsible for thinking, remembering and planning. With the exception of these regions performing the high order brain functions, the other regions exhibit a high level of localization in both structure and function. Contribution of Bio-psychological Factors to Normal and Abnormal Behavior Bio-psychological factors have the potential of altering behavior in several ways. Such factors often trigger action from the central nervous system, autonomous and endocrine system. The resulting responses lead to behavior adjustment. Psychologists define abnormal behavior as any deviation from the societal description of normal. Abnormal behaviors include exhibition of antisocial behaviors while normal behavior includes any behavior in the range of the societal definition of normal. For example, exhibiting social behavior that matches society’s definition of normal from the social cues is acceptable. Behavior change results after any influence from the nerves or the endocrine system (Nevid, 2009:56). In cases of abnormality, alterations in the brain functions results to abnormal behavior. Any inefficiency in the hormonal system can contribute to the wrong response causing an abnormality of the ultimate behavior change. Moreover, any abnormality in the brain regions will result to abnormal behavior. Inadequate homeostatic control also has the potential of altering behavior in the individual resulting to abnormal responses. Since the central nervous system, endocrine system and the autonomous system exhibit a connection, any deficiency in the three systems translates to abnormal behavior. Diagram showing the contribution of bio-psychological factors on behavior Available from http://www.google.co.ke/imgres?hl=en&client=firefox-a&hs=Syx&sa=X&rls=org.mozilla:en-US:official&channel=fflb&biw=1024&bih=609&tbm=isch&tbnid=DKF5xeC0-EpsmM:&imgrefurl=http://www.sciencedirect.com/science/article/pii/S1357272598000946&docid=w8Oo2UQG2gb0GM&imgurl=http://ars.els-cdn.com/content/image/1-s2.0-S1357272598000946-gr2.jpg&w=722&h=504&ei=P60nUY6II4nfkAXY1YH4Cw&zoom=1&ved=1t:3588,i:114&iact=rc&dur=812&sig=116218172592145167772&page=1&tbnh=175&tbnw=236&start=0&ndsp=15&tx=133&ty=75 Electrochemical and Neuro-Chemical Activity in the Brain In the brain, relaying of messages occurs through both chemical and neuro-chemical activities. The brain has the capacity to interpret the relayed signals and send back responses to the concerned body part. The response delivered causes a change in the target organ, and then behavioral changes occur depending on the response. Therefore, any chemical activity or interactions of the neurons in the brain are of great concern to scientists. This is because the type of changes occurring in the brain determines the behavior that results in the end. The brain is the central controller of all the body parts and behavior change is the evidence of the activities that transpire in its faculties (Spiegel, 2003:108). Chemical and neuro-chemical activities in the brain represent its perception of the multiple signals that it must address. It is impossible to underestimate the roll of the chemical and neuro-chemical activities and scientists have relied on the understanding of such activities to explain behavior. Neurons are responsible for relaying both the electrochemical and neuro-chemical information (Spiegel, 2003:120). These cells release transmitters such as dopamine, epinephrine, and nor epinephrine. There are different categories of neurons with each having its unique adaptations. These adaptations determine which transmitter the cell can release. Effects of Drugs on Behavior Drugs that have the capacity to alter behavior belong to the category of lipid-soluble drugs that have the potential of crossing the brain barrier. In entry into the brain, such drugs can cause changes in the activities of the brain, eventually causing behavior change. Depressants and stimulants are some of the drugs that exhibit the capacity of crossing the brain barrier and exerting their influence on the brain (Brodal, 2010: 45). Depressants exert negative influence by slowing down the rate of brain activity. Physicians advise that depressants serve as a good remedy for restlessness and lack of sleep. As they exert their effect on the central nervous system, the individual experiences a calming effect. On the other hand, stimulants serve to register a rise in brain activity. The increase translates to high blood pressure and heart rate. Increase in brain activity occurs through an abundant availability of neurotransmitters (Clarke, Dewhurst, & Aminoff, 2006:5). Stimulants trigger the release of the important molecules that initiate faster brain activity. These molecules include epinephrine, serotonin, dopamine, and nor-epinephrine, and serve, as transmitters in brain cells (Spiegel, 2003:84). The transmitters released often attach to receptors and trigger electrochemical reactions. The brain deciphers these reactions, and causes behavior change. As illustrated below, different levels of the transmitters translate to a wide range of behavioral effects. There are other substances such as caffeine that present the potential of acting like stimulants presenting both multiple behavioral changes. This serves to present evidence concerning the over-activity exhibited by regular caffeine consumers. Researchers have identified that even medically accepted drugs present unwanted effects on the central nervous system, altering behavior further (Clarke, Dewhurst, & Aminoff, 2006:10). Diagram showing the mode of action of stimulants through the production of important molecules Available from http://www.google.co.ke/imgres?imgurl=http://ars.els-cdn.com/content/image/1-s2.0-S0079612308009199-gr2.jpg&imgrefurl=http://www.sciencedirect.com/science/article/pii/S0079612308009199&usg=__g9emHi3OeD2EuthLdWMDbglwCU0=&h=359&w=433&sz=52&hl=en&start=6&zoom=1&tbnid=tGCL8Qz-OrgI1M:&tbnh=104&tbnw=126&ei=tdQoUch1xMy0BsbtgLgM&itbs=1&sa=X&ved=0CDQQrQMwBQ Diagram showing how Methamphetamine affects the central nervous system Available from http://www.google.co.ke/imgres?hl=en&client=firefox-a&hs=fl8&rls=org.mozilla:en-US:official&channel=fflb&biw=1024&bih=609&tbm=isch&tbnid=Pg6D55c3JGEPvM:&imgrefurl=http://hypnothai.wordpress.com/tag/methamphetamine/&docid=IXRHVNVbAZGz6M&imgurl=http://hypnothai.files.wordpress.com/2011/07/adverse_effects_of_methamphetamine.jpg%253Fw%253D505%2526h%253D400&w=505&h=400&ei=Uk8oUcDPI4SUtQbFr4DgBQ&zoom=1&ved=1t:3588,i:347&iact=rc&dur=378&sig=116218172592145167772&page=6&tbnh=158&tbnw=199&start=81&ndsp=17&tx=89&ty=55 Bodily Mechanisms Underlying Stress One of the mechanisms underlying stress is the cortisol-producing pathway. The hormone cortisol produced during stressful moments has unseen effects that affect the individual. Scientists have realized that the hormone possesses the potential of altering the telomerase activity in immune cells (Geter, 2010:39). As a result, the cells lack the inability to regulate the length of the telomere produced in the new immune cells. Therefore, the hormone leads to the production of immune cells with a telomere deficiency, a feature that results to limited activity. Consequently, the body lacks the capacity to counter infections. This is the reason why the body becomes very susceptible to infections during stress. In its chronic levels, stress can later numerous body mechanisms. The body releases certain hormones during stress, and these are responsible for altering body mechanisms, exposing the body to vulnerability, and making it deteriorated. Research reveals that stress intensity depends on the level of cortisol produced. Any changes in the mechanism will give rise to other stress-related disorders. The brain always exhibits a reaction to any changes that occur in the body. Potential Sources of Stress Stress is the condition that results when feelings of uncertainty overwhelm an individual. The uncertainties that have the potential to overwhelm an individual often may emanate from different sources. Some people find some environmental factors quite unbearable, resulting into different levels of stress. For others, stress may result from political or technical sources. When the demands from these become overwhelmingly unbearable, an individual may experience stress (Geter, 2010:2-24). Economic uncertainties have proved to exert enormous unwanted pressures to people causing stress in the end. Moreover, organizational factors can present too many demands to the individual, and this is the leading cause of work-related stress. Researchers have attributed many sources of stress to personal factors. These may emanate from the self, family, or personality. For many individuals, life situations often disappoint, presenting them with a new worry each day. There is need for such people to devise a mechanism of overcoming the inherent daily setbacks and be able to achieve their goals. Consequently, the undying pressure of striving to achieve personal goals has the potential of causing a consistent occurrence of stress. Although determination and ambition are essential, they may drive an individual to overwork him or herself. Stretching oneself beyond personal limits registers a high level of stress (Geter, 2010:34). Treatment of Stress and Anxiety In order to get relief from stress and unnecessary anxieties, it is critical for an individual to analyze his or her situations and recognize the central cause of stress (Geter, 2010:42). It is only after then that an individual can embark on searching for a relevant remedy. More often, people have to readjust their perception towards certain factors in life. In other cases, an individual may have to accept the unchangeable factors in life. If new strategies can help in putting the uncertainties under control, then the individual must work on developing strategies that are more efficient. This concept has proved effective in relieving work-related stress. A healthy lifestyle can also reduce the levels of stress through re-energizing the body through exercise and providing it with the necessary nutritional requirements (Geter, 2010:39). Exercise serves in rejuvenating the body and making it revitalized a factor that goes well with boosting the immune system (Lehrer, Woolfolk, & Sime. 2007:249). Exercise leads to the release of transmitters that boost moods, emotions, and behavior change. People who observe a regular exercising routine prove to be more adaptable to stressing conditions. In conclusion, it is evident that the central nervous system plays a critical role in maintaining control over all the body parts. The localization of brain functions described above helps in ensuring timely addressing of all the necessary processes. On the other hand, the endocrine system influences some processes in target organs through the release of hormones. The autonomous system also plays a critical role in ensuring homeostatic balance. The three systems work together and influence behavior in different ways. However, the brain serves as the central regulator of all activities. Bibliography Brodal, P. 2010. The central nervous system: structure and function. New York, Oxford University Press. Burstein, J. (2009). The exciting endocrine system: how do my glands work? St. Catharines, Ont, Crabtree. Clarke, E., Dewhurst, K., & Aminoff, M. J. 2006. An illustrated history of brain function: imaging the brain from antiquity to the present. San Francisco, Calif, Norman. Geter, L. 2010. 47 steps to stress management: real help for stress relief and the prevention of premature aging. Charleston, S.C., Booksurge. Lehrer, P. M., Woolfolk, R. L., & Sime, W. E. 2007. Principles and practice of stress management. New York, Guilford Press. Nevid, J. S. 2009. Psychology: concepts and applications. Boston, Houghton Mifflin Co. Qu, Z. 2009. Cooperative control of dynamical systems: applications to autonomous vehicles. London, Springer. Riva, D., Njiokiktjien, C., & Benton, A. L. 2010. Brain lesion localization and developmental functions: basal ganglia, connecting systems, cerebellum, mirror neurons : remembering Arthur L. Benton. Montrouge, France, John Libbey Eurotext. Scott, A. S., & Fong, E. 2009. Body structures & functions. Clifton Park, N.Y., Delmar. Spiegel, R. 2003. Psychopharmacology an Introduction. Chichester, John Wiley & Sons. http://public.eblib.com/EBLPublic/PublicView.do?ptiID=164848. Read More