Medulla Oxygen Content Analysis

The decrease in her PCO2 and pH will cause her central nervous system to slow down causing her breathing to slow down to try to give her body more carbon dioxide to level out the amount of oxygen/carbon dioxide ratio.

The same happens with Carbon Dioxide (CO2). The blood in the surrounding capillaries has a higher concentration of CO2 than the inspired air due to it being a waste product of energy production. This is when O2 and CO2 pass each other going back around the body systems to the heart. Once this is done the flow goes from Deoxygenated blood to Oxygenated blood.

At higher altitudes respiration rate is increased which leads to increases in ventilation (possibly a five-fold increase from sea level). Chemoreceptors in the arterial blood vessels are stimulated to signal the brain to increase ventilation. The increase in ventilation is associated with increased breathing frequency and tidal volume.

This results in the person having repetitive periods of insufficient ventilation and jeopardized gas exchange. This occurs when the inhibitory input to the brain exceeds excitatory output; or in simpler terms the brain fails to signal the muscles to breathe.

PCO2 decreased during rapid breathing because more CO2 was removed from the blood than normal. Each breath expels a certain amount of CO2. If the breathing rate increases, then more CO2 is expelled.

High alveolar ventilation brings more O2 into the alveoli, increasing O2 , and rapidly eliminating CO2 from the lungs (for chemical abbreviations see Table 2).

The centre can pick up PH levels in the blood and receives information via chemoreceptors around the body which detect the change in pH levels. We can see if there is a change of carbon dioxide levels in the blood by noticing the change in PH. Ventilation and diffusion will increase drastically through the respiratory system in a reaction to exercise your breathing rate and debt will increase if your ventilation rises, the inspiratory centre controls this by stimulating the diaphragm and external intercostal muscles. The expiratory centre also controls this by being able to also stimulate the expiratory muscles which happen to be the internal intercostal muscles, oblique’s and rectus abdomens. This causes a forced expiration which reduces the duration of inspiration. Tidal volume is the amout of air taken in and relsed from the body in each breath so in vigerous exercise your tidal volume will be much higher contrasting with your body at a normal relaxed pace This is usually around 500cm cubed. Tidal volume increases to around 3-4 litres during exercise, this increase takes place as your breathing increases dramatically to compensate for the oxygen debt in your muscles . increasing the tidal volume is a good thing, it flushes out carbon dioxide and allows us to inhale plenty more oxygen to be

Hypoventilation after hyperventilation has a lower arterial pCO2, pO2 and Hb-O2 saturation than hypoventilation but longer in the duration of breath holding. As the blood pH is higher because of pre-clearance of CO2 by hyperventilation in advance, it then takes longer to accumulate CO2 to be sensed by medulla oblongata, urging to breath (Woischneck et al., 2009), compares to only hypoventilation, a shorter duration for beginning with a normal range of pCO2. As the supply of oxygen solely based on the amount pre-breathed in during hypoventilation, the experiment with hyperventilation has a higher

Pulmonary (external) respiration or ventilation involves the intake of oxygen, and the elimination of carbon dioxide from the body. While oxygen is an essential element to the in the production of energy, and the first thing that comes to mind when the topic is about breathing, it is the carbon dioxide that plays the most important role when it comes to the regulation of ventilation (Pearson 12). Contrary to what most people believe, carbon dioxide is more than just a waste product of the body’s metabolic process called aerobic (internal) cellular respiration. Blood levels of CO2 play a vital role in controlling rates of breathing that that has a corresponding effect on the blood’s pH levels. Blood’s pH imbalance or irregularities and troublesome

These results are due to metabolic rates and the need for homeostasis which is driven by the production of CO2 (Mason, 2015). The results suggest that the values obtained in the normal ventilation condition for PO2, PCO2 and %O2 are consistent with the proposed values 100 mmHg, 40 mmHg and around 98% (Silverthorn, Johnson & Ober, 2013, p. 590). This is due to arterial gas composition being approximately equal to alveolar gas composition (Silverthorn, Johnson & Ober, 2013, p. 590). The breath-hold after hypoventilation condition resulted in an increased CO2 intake into the lungs due to breathing deeply. There was a decrease in PO2 and %O2 and increase in PCO2 as arterial PCO2 rose because metabolic processes continued without a new intake of air into the lungs. This disturbance of respiratory homeostasis hinders the ability to hold one’s breath (Mason, 2015). CO2 decreases pH of extracellular brain fluid, which stimulates central chemoreceptors, causing a break-point in breath-hold (Moreira, Takakura, Colombari & Guyenet, 2006). CO2 is detected very quickly in the blood (respiratory acidosis) by peripheral chemoreceptors (carotid and aortic bodies) (Miller, Cunningham, Lloyd & Young, 1974). The respiratory centre is controlled by chemoreceptor response, which then re-establishes respiratory homeostasis, by inducing a change in ventilation (Haldane & Priestley, 1905). However, the hyperventilation pattern, which involved shallow breathing, caused an increase in PO2 due to greater accumulation rate of O2 and larger O2 store in the lungs. A reduction in arterial PCO2 and increased expiration of CO2, increased %O2, which explains why there was a reduction in PCO2 (Lindholm &

Control centers: the medulla oblongata and neural circuits establish a person’s breathing rhythm that gathers information from the internal environment to coordinate breathing based on the body’s need for oxygen. To accomplish this, the sensors in the medulla monitor the pH of the cerebrospinal fluid to indicate the concentration of carbon dioxide in the body. A normal pH is about ~7.4. When the blood pH falls below this range, the medulla’s sensors detect a low pH in the cerebrospinal fluid and blood. This cause the ribs and diaphragm to increase their rate of rate of ventilation, causing the carbon dioxide level in the blood to fall and raising the blood and cerebrospinal fluid pH once again. The higher the carbon dioxide level, the more hydrogens that are present in a substance, causing its pH to

Gas exchange occurs between the air and blood in the lungs. Since the oxygen saturation of air is higher in the lungs than in the blood, oxygen diffuses from air to blood. Carbon dioxide moves from the blood to the air within the lungs by diffusing down its concentration gradient. As a result of this exchange, the inspired air contains more oxygen and less carbon dioxide than the expired air. The lungs provide necessary oxygen to the body, in addition to removing carbon dioxide. More importantly, blood leaving the lungs has a higher oxygen and lower carbon dioxide concentration than the blood delivered to the lungs in the pulmonary arteries. This is because the lungs function to bring the blood into gaseous equilibrium in the air. Gas exchange between the air and blood occurs entirely by diffusion through the lung tissue

The result of this is that air becomes trapped in the alveoli, and prevents O2 rich air from entering the lungs.

This event was simulated during the re-breathing exercise. Unlike hyperventilation, where the subject had a long breath-hold and a small carbon dioxide composition, re-breathing had the shortest duration and the highest percent of carbon dioxide. The test subject was able to hold her breath for only 27 seconds. While her CO2% before the breath-hold was 6.23% and after was 6.61%. This short duration of breath hold was attributed by a low concentration of oxygen in the arterial

low, the oxygen in our body diffuses into tissues, allowing carbon dioxide in the blood (Pendleton, 2003).