Alveolar Gas Exchange Lab Report

Gas exchange is when oxygen is delivered from the lungs to the blood stream and carbon dioxide is taken out of the bloodstream and into the lungs. Gas exchange occurs within the lungs between the alveoli and capillaries which are in the walls of the alveoli. The walls of the alveoli share a membrane with the capillaries in which oxygen and carbon dioxide move freely between the respiratory system and the bloodstream. Oxygen molecules attach to red blood cells, which travel back to the heart. At the same time, the carbon dioxide in the alveoli are exhaled out of the body.

Emphysema damage to the alveoli causes a significant decrease in the surface area available for adequate gas exchange ability.

This refers to the process of Oxygen and Carbon Dioxide moving between the lungs and blood. Diffusion occurs when molecules move from an area of high concentration to an area of low concentration. This occurs during gaseous exchange as the blood in the capillaries surrounding the alveoli has a lower oxygen concentration of Oxygen than the air in the alveoli which has just been inhaled. Both alveoli and capillaries have walls which are only one cell thick and allow gases to diffuse across them. The same happens with Carbon Dioxide. 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. Therefore CO2 diffuses the other way, from the capillaries, into the alveoli where it can then be

Naturally, there is an anatomical dead space within the respiratory system where gas exchange cannot occur. This is at any point in the respiratory system other than the alveoli. When the alveoli become involved, all of these spaces are the physiological dead space. The increase in physiological dead space is irreversible, and causes prolonged effects including air

Hyperventilation (over-breathing) lowers the tension of CO2 in alveolar air, less fresh air enter the alveoli and respiratory rate increase without increase metabolism (Eugene & Stead, 1960); (Silverthorn, 2010). In addition, the rate of breathing are control by the respiratory centre in the medulla. The activity of the respiratory centre can be influenced by oxygen, carbon dioxide and hydrogen ions which are monitor by peripheral and central chemoreceptors in the medulla. Chemoreceptor also determine the duration of breath hold, the length of breath hold reduce when oxygen concentration in blood decrease and carbon dioxide concentration in blood increase. When carbon dioxide concentration is high, reach the breaking point, around 50mmHg (McArdle,

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

Normally, lungs take in oxygen and remove by exhaling, CO2. Oxygen passes from the lungs into the blood, and CO2 passes from the blood into the lungs. However, if the lungs can not remove the right amount of CO2, respiratory acidosis can occur.

I have decided to do points 1 and 4. At point 1 which is the alveoli of the lungs the PPO2 is 104 mm Hg and the PPCO2 is at 40 mm Hg. At point 4 which is the inspired air the PPO2 is 160 mm Hg and the PPCO2 is at 0.3 mm Hg. The gaseous makeup which originates from the atmosphere is different from within the alveoli. Majority of the alveoli is CO2 and water vapor and minimal O2. The differences of this is a reflection of effects that the gas exchanges that occurs in the lungs. One being the O2 diffuses from the alveoli then travels to the pulmonary blood and then the CO2 diffuses in the complete opposite direction. two being the humidification in the air from the conducting passages. Thirdly, mixing that occurs of the alveolar gas which happens

Despite the lack of innovative technology, Krogh et al. determined that ventilation was constant after an initial increase onset of the heavy work. There was a higher rate of O2 consumption, which results in higher pulse rate, increased circulation thus an increase in O2 absorption. In one of their experiments to clarify the initial increase in O2 absorption, they added 3% CO2 to their subjects and showed there was a “considerable increase in the initial ventilation with the same amount of work performed”. Krogh et al. showed the regulatory mechanism of chemoreceptors’ responsibility in detecting the changes of CO2 levels and how the body responds to it. Krogh et al. also cites Hasselbalch et al. 1912 to show similar results in an initial increase of ventilation after onset of heavy work and increased levels of CO2. They further showed the effects of O2 to “diminish the excitability of the centre”, referring to a respiratory center, a concept that Krogh et al. were trying to suggest the connections of the regulation of ventilation and circulation in the initial stages of exercise. Krogh et al.’s study proved to be a breakthrough and a stepping-stone in further studies and research in regulation of ventilation during

Both go through gas exchange in the lungs to change the CO2 to 02 which is then removed from the body

Gas exchange takes place in the lungs, and more precisely in the alveoli, the tiny little air sacs deep inside the lungs. The exchange takes place between the alveoli and the capillaries that surround the alveoli. The because there are millions of alveoli, this increases the surface area for gas exchange and makes the alveoli specialised for what they do. The walls of the alveoli are permeable and only one cell thick so gas exchange happens easily. The blood in the capillaries around the alveoli return from the body full of carbon dioxide

The human lung is a series of blind end tubes, hollow tubes that that allow for the conduction of air. The conduction of air starts from the nasal cavity or oral cavity, continues to flow through the trachea and bronchus and finally reaches the bronchioles that lead into the alveolus that allows for gas exchange to occur (Phalen et al. 1983). This system can be broken down into two different region; a conducting region and a region of gas exchange. The conduction portion of the respiratory system begins in the nasal cavity and the oral cavity and continues to the bronchioles. The transition from the bronchioles to the alveolar duct results in the transition from the conducting region of the respiratory

Hyperventilation elevates the subject’s ability to hold their breath by reducing the PCO2 level in the blood. Hence, breathing will start a bit late when PCO2 reaches its threshold level which will activate the chemoreceptors in the respiratory center. Consequently, the chemoreceptors will send a signal to the control center in the brain stem which will respond to the somatic motor neurons and trigger the respiratory muscles to start the breathing again.

Gaseous exchange is the delivery of oxygen from the lungs to the bloodstream, and the elimination of carbon dioxide from the bloodstream to the

This allows more space in the lungs and decreases the pressure within them, meaning air flows into the lungs because of the decrease in pressure. This air enters the body through either the mouth or nasal passages and mixes together when they enter the pharynx. The air then travels down the airways (trachea, bronchi and bronchioles) to the gas exchange surface. Carbon dioxide is expelled from a mammal’s gas exchange system by exhalation. The external intercostal muscles and diaphragm