HEALTHY BODY SYSTEMS 7
Therespiratory system is one of the most fundamental systems in thehuman body. It is primarily charged with obtaining oxygen that is tobe used by body cells and getting rid of carbon dioxide that isproduced by the cells in their varied functions. The respiratorysystem is composed of the lungs and the airways that lead to and outof the lungs. Underlining its importance in the human body is thefact that it undertakes the regulation of the blood pH, as well asthe levels of carbon dioxide and oxygen.
Inspiration and expiration in a resting person.
Inmost cases, the rate of breathing in an individual is usuallymeasured when he or she is in a resting position. Breathing refers tothe mechanical process that animals perform automatically using therespiratory system consisting of the bronchi, diaphragm, lungs andtrachea. Breathings starts with inhalation, which occurs whenoxygen-rich air becomes sucked into the human body. Inhalation isinitiated by the diaphragm through the contraction of its muscles(Rogers,2011).This contraction enlarges the chest cavity, in which case the lungsfail to feel pressure from outside thereby allowing the air to bepulled into the body so that pressure can be equalized. In essence,the air enters the nose and mouth, moves through the trachea into thebronchi, right to the bronchioles and into the alveoli (Zaugg &Luccinetti, 2000). Every lung is made up of more than 300 millionalveoli, which expand once the air get into the body via thebronchioles. The alveoli have capillaries full of blood surroundingthem (Rogers,2011).Since the air-blood barrier is extremely thin, the oxygen gets intothe blood, while the carbon dioxide from the body flows into thealveoli from the air. The gas exchange is called diffusion as itrequires no effort or energy from one’s body.
Thisis the final process in the breathing process and occurs after theoxygen is in the blood and has been pumped throughout the body (Smithet al, 2010). The reverse process occurs where the diaphragm musclesrelax thereby adding pressure to the chest cavity, which eventuallyforces the unclean air to the bronchioles from the alveoli. Thiscarbon dioxide is then moved through the tubes before being takenthrough the trachea back to the nose and mouth and being expelled.
Variations in Lungs’ Volume in Vigorous Breathing
Duringvigorous breathing, the volume of the lungs increases by as much as15 %. This is especially in the case of exercising. Scholars havenoted that an individual’s breathing becomes faster and deeper soas to meet the metabolic demands of the body in the course ofexertion. This allows for the delivery of more oxygen to the musclecells and the heart. Carbon, dioxide, which is a byproduct ofrespiration would be released in the course of the exhalation. Ofparticular note is the fact that the changes in lung volumes isaugmented by changes in various muscles in one’s body.
Thelungs are protected by the ribs in one’s chest. These ribsincorporate a rigid structure that does not have the capacity toexpand beyond a certain limit. When measured using a spirometer,tidal volume underlines the amount of air that an individual wouldtake in with each breath. When an individual is at rest, this volumeis about 500 ml and 600 ml in females and males respectively (Smithet al, 2010). The largest likely tidal volume is known as vitalcapacity, which is about 3.2 and 4.8 liters in females and malesrespectively.
Duringvigorous breathing, air would be forced into one’s lungs as aresult of thoracic cavity expansion, which is caused by theflattening out of the diaphragm at the rib cage’s bottom, as wellas the external intercostals muscles’ contraction. This expansionof thoracic cavity causes a decrease in thoracic pressure and anincrease in thoracic volume, thereby allowing for a decrease inthoracic pressure and the cascade of air to the lungs (Sharma &Goodwin, 2006). During exercise, there is an increase in rate ofventilation as a result of the body’s increased need for oxygen.Further, the depth of breathing would increase as a result of theanatomical dead space in the respiratory system (Smith et al, 2010).This anatomical dead space is in one’s mouth, tracheas, bronchiolesand bronchi, larynx and the trachea. Upon inspiration, the air wouldreach the alveoli first. Due to the prolonged exposure to tissues,the air would have a higher Carbon dioxide concentration, in whichcase an increase in breath depth results in an increase in theproportion of fresh air getting into the alveoli (Shaw et al, 2010).
Physiological and Anatomical Changes in the Respiratory System of Elderly Adults
Thereare varied changes that take place in the breathing system of anormal human being. Scholars have noted that the potential latency ofthe diaphragmatic compound action that is evoked by the stimulationof the phrenic nerve increases with age, while the action potentialamplitude is decreased (Sharma & Goodwin, 2006). These changesare seen as a representation of the disproportionate degeneration ofthe larger myelinated phrenic nerve fibers, which plays a role in thereduction of the contractile strength of the diaphragm.
Inaddition, as an individual gets older, he or she undergoes a gradualincrease in the pulmonary vasculature’s stiffness, as a result ofan increase in the thickness and content of the muscles (Lalley,2013). Related to the structural remodeling, there is a gradualincrease in the in the pulmonary wedge pressure and the arterialpressure, which becomes considerably elevated after the age of 50.Further, the capability for the lungs’ gas exchange is compromisedin relation to the reduced volume and number of the pulmonarycapillaries (Lalley, 2013).
Otherphysiological changes that take place in the elderly include the lossof the strength and mass of the intercostals muscle, deterioration ofthe neuromuscular junctions, vertebral and rib cage cartilagearticulations calcifications, as well as the narrowing of the spacesf the intervertebral disk, all of which contribute to the reductionof the compliance of the chest wall (West,2008).Other changes that occur in the structure of the lung include thedisruption and loss of the elastin fibers in an individual’sbronchioles (Lalley, 2013). Further, there is a reduction in thelungs’ gas exchange capability as a result of the reduction in thevolume and number of the pulmonary capillaries.
Effects of Long-term Exercises on Respiratory System
Thereare varied modifications that are carried out on the respiratorysystem as a result of carrying out various exercises in thelong-term. It is well noted that in the course of exercising, themuscles would demand more oxygen, which obviously results in theproduction of more carbon dioxide. This would necessitate that thebody undergoes varied adaptations especially in its respiratorysystem so as to combat the demands.
First,the respiratory muscles would have their strength increased. As aresult of regular exercising, there would be an increase in theactivity of the respiratory muscles so as to meet the demand foroxygen and eliminate the carbon dioxide produced (Hlastala&Berger, 2001).This necessitates an increase in their strength.
Secondly,there would be an increase in the vital capacity of the lungs. Thevital capacity is the largest tidal volume (amount of air that anindividual would take in with each breath). This is aimed at meetingthe increased demand for oxygen in one’s body so as to meet thedemands of the increased metabolism (West, 2008).
Onthe same note, there would be an increase in the minute ventilationor the amount of air than an individual breathes within a singleminute. For a normal person, the tidal volume is about 8-10 ml per kg(West,2008).This would increase with increased exercises so as to meet theheightened demand for oxygen and elimination of carbon dioxide.
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