The lungs, with many alveoli of various sizes are inherently unstable. Surface tension in the lungs between the alveolar gas and the fluid lining the alveoli plays an important role here. Alveolar instability due to surface tension is produced as described below:
When two alveoli with different radius connect with each other, the amount of pressure generated (P) in each is, P= (2 × surface tension)/radius. Therefore, when the surface tension is constant, the pressure in the smaller alveolus will be more than the larger alveolus, which makes the lungs unstable. In other words, the unstable situation in the lungs is that, a smaller alveolus has higher pressure, while a larger alveolus has lower pressure. The instability is primarily caused
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This effect of carbon dioxide on the hemoglobin’s capacity to combine with oxygen is known as the Bohr effect. The physiologic advantage of the Bohr effect is that it serves to enhance O2 uptake in the lungs and delivery of O2 to tissues. Listed below are 3 situations in which the Bohr effect is beneficial to …show more content…
Moreover, vasa recta not only bring nutrients and oxygen to the medullary nephron, but also remove excess water from the medullary interstitium. The blood plasma, as it enters vasa recta is isotonic (300 mOsm) with respect to the interstitum. As plasma makes it way down into the medullary interstitial fluid, it is encountering increasingly hyperosmotic interstitial fluid (ISF). Since it’s a capillary, there is a free exchange of water and solute between the vasa recta and the medullary ISF. As plasma moves down the descending loop of Henle, due to hyperosmotic ISF, water moves out and sodium and chloride move into the bloodstream. At the end of the descending loop of Henle, the concentration of salt inside the rasa recta is around 1200 mOsm. Now, as plasma moves up the ascending loop of Henle, sodium and chloride move out and water move into the bloodstream. The ascending loop of Henle cannot remove the added water because they are water-impermeable. The vasa recta remove the water; this is why blood flow in the ascending vasa recta exceeds blood flow in the descending vasa recta. Interestingly, sodium and chloride that are moved out of the vasa recta in the ascending loop of Henle enter the descending loop of Henle and the cycle continues. The countercurrent exchange process is passive and it helps maintain an electrochemical gradient.
The final concentration
Air then travels to the bronchioles which are narrow (bronchoconstriction) due to the natural defence in keeping irritants out of the airway, causing wheezing breath sounds.(Eldridge, 2016) The air then proceeds to the alveoli, which are weakened and damaged air sacs due to the progression of the disease, that are unable to efficiently move O2 into the blood stream and gas exchange CO2 to be expelled through exhale, causing hypoxemia, lethargy, dyspnoea and high CO2 reading. (“Lung conditions - chronic obstructive pulmonary disease (COPD),”
Pulmonary stenosis (PS) - Pulmonary Stenosis causes an obstruction of blood flow from the right ventricle into the pulmonary arteries. This obstruction causes the right ventricle to have more difficulty pumping the oxygen-poor blood received from the vena cava to the lungs in order to pick up the oxygen needed. Therefore causing a decrease in exchange of oxygen in the lungs, as well as a decrease of blood volume to the lungs.
Respiratory distress syndrome type I is a decrease production of surfactant, a noncelluar chemical produced in the type II alveolar in the lungs that's primary function is to decrease the surface tensions and attraction between the type I alveolar walls. Respiration requires the alveolar walls to inflate and deflate continuously, while ventilating the alveoli are exposed to moisture causing an attraction between the alveolar walls. (Kenner, Lott, & Flandermeyer, 271) Surfactant primary function is to neutralize the attraction to prevent alveolar collapse during deflation.
In this activity Effects of Arteriole Radius on Glomerular Filtration was recorded with valve opened and closed when blood pressure changed. When the one-way valve between the collecting duct and the urinary bladder was closed the filtrate pressure in Bowman’s capsule (was not directly measured) and the GFR pressure stayed the same and glomerular filtration decreased. Increasing the systemic blood pressure stayed the same when valve was closed and GFR was low when the valve was open.
In the lungs gas exchange occurs to re-oxidize the blood. Air travels through the respiratory tract to reach the lungs and back up to be exhaled into the environment. At the termination point of the respiratory tract lays the alveoli. The alveoli have a sac-like structure. In biological systems, the structure and functions of components are related. The alveoli have a structure specialized for efficient gaseous exchange. In the structure of the alveoli (alveolus), it looks as if it has the form of a hollow cavity that is paired with elastic fibers...
Fluid from the intravascular space shifts into the interstitial space surrounding the cells. This shift is caused by increased hydrostatic pressure within capillaries as the result of reduced liver function blocking blood flow. Increased capillary permeability from inflammation pushes albumin into the interstitial space, increasing interstitial osmotic pressure and deceasing capillary osmotic pressure. Due to decreased liver function, albumin is not longer readily made decreasing its presence in body. Without albumin, osmotic pressure will remain decreased within the plasma. As the body compensates for this loss of water and increased sodium in the intravascular space hypertonic alterations pull water from the intracellular fluid causing
As mentioned above, emphysema affects the alveoli. When you develop emphysema the symptoms may go unnoticed for many years. With emphysema, your alveoli lose their elasticity and that makes it harder for the body to dispel the carbon dioxide. Also, the alveoli will eventually rupture and develop into one larger air sac. (Mayo Clinic)
Pneumonia is an inflammatory response that results in an excess amount of fluid in the interstitial spaces, the alveoli, and the bronchioles. It is caused by the inhalation of organisms or irritants that move into the alveoli when the immune system is not strong enough to combat it. Once these organisms or irritants enter the lungs, they reach the alveoli where they begin to multiply. This multiplication of these organisms results in white blood cells traveling into the area subsequently causing local capillaries to become edematous, leaky, and to create exudate. The combination of this results in thickening of the alveolar wall due to fluid collection within and around the alveoli. Impaired gas exchange, which is the ...
In normal breathing, the lungs expand and contract easily and rhythmically within the ribcage. To facilitate this movement and lubricate the moving parts, each lung is enveloped in a moist, smooth, two-layered membrane (the pleura). The outer layer of this membrane lines the ribcage, and between the layers is a virtually imperceptible space (the pleural space), which permits the layers to glide gently across each other. If either of your pleurae becomes inflamed and roughened, the gliding process is impeded and you are suffering from pleurisy. Pleurisy is actually a symptom of an underlying disease rather than a disease in itself. The pleurae may become inflamed as a complication of a lung or chest infection such as pneumonia or tuberculosis, or the inflammation may be caused by a slight pneumothorax or chest injury. The pleural inflammation sometimes creates a further complication by causing fluid to seep into the pleural space, resulting in a condition known as pleural effusion. However, pleurisy is not the only condition that can lead to pleural effusion, it may also be produced by diseases such as rheumatoid arthritis, liver or kidney trouble or heart failure. Even cancer spreading from the lung, breast or ovary can cause pleural effusion. If you have pleurisy, it hurts to breathe deeply or cough, and chest pain is likely to be severe. Accompanying the pain are any other symptoms associated with the underlying disorder. The pain will disappear if a pleural effusion occurs as a consequence of pleurisy, because fluid stops the layers of the pleura from rubbing against each other; however, you may become breathless as the fluid accumulates. In most cases, the risks are those of the underlying cause. A big pleural effusion can compress the lungs and cause breathlessness. Any effusion may lead to empyema. A chest X-ray examination may be required.
However, with pulmonary edema the alveoli fill with fluid instead of air. Pulmonary edema is the ending result of abnormal build-up of fluid leads to shortness of breath. The term edema itself generally means swelling. This can happen either because of too much pressure in the blood vessels or not enough proteins in the bloodstream to hold on to the fluid in the plasma; the part of the blood that does not contain any blood cells (Medicinenet). This lung condition is usually caused by a number of cardiac and non-cardiac conditions such as: Coronary artery disease, cardiomyopathy, heart valve problems, high blood pressure, acute respiratory distress syndrome, high altitudes, nervous system conditions, adverse drug reactions, pulmonary embolism, and smoke inhalation (Brunner 2015). These many conditions are all health related problems that should be examined by a
The respiratory system is a complex organ structure of the human body anatomy, and the primary purpose of this system is to supply the blood with oxygen in order for the blood vessels to carry the precious gaseous element to all parts of the body to accomplish cell respiration. The respiratory system completes this important function of breathing throughout inspiration. In the breathing process inhaling oxygen is essential for cells to metabolize nutrients and carry out some other tasks, but it must occur simultaneously with exhaling when the carbon dioxide is excreted, this exchange of gases is the respiratory system's means of getting oxygen to the blood (McGowan, Jefferies & Turley, 2004).
Asthma is a chronic disease that makes it difficult to breathe. The airways to the lungs swell up and become inflamed, which narrows the air passageway to the lungs and the lungs cannot receive the amount of oxygen that it needs. “Mucus builds up inside the airways so you have trouble getting air in and out of your lungs.” (Pope, 2002, p.44). If the lungs do not receive the essential amount of air, it will cause a lot of distress and wheezing to the patient.
Healthy lung tissue is predominately soft, elastic connective tissue, designed to slide easily over the thorax with each breath. The lungs are covered with visceral pleura which glide fluidly over the parietal pleura of the thoracic cavity thanks to the serous secretion of pleural fluid (Marieb, 2006, p. 430). During inhalation, the lungs expand with air, similar to filling a balloon. The pliable latex of the balloon allows it to expand, just as the pliability of lungs and their components allows for expansion. During exhalation, the volume of air decrease causing a deflation, similar to letting air out of the balloon. However, unlike a balloon, the paired lungs are not filled with empty spaces; the bronchi enter the lungs and subdivide progressively smaller into bronchioles, a network of conducting passageways leading to the alveoli (Marieb, 2006, p. 433). Alveoli are small air sacs in the respiratory zone. The respiratory zone also consists of bronchioles and alveolar ducts, and is responsible for the exchange of oxygen and carbon dioxide (Marieb, 2006, p. 433).
Alveolar hyperventilation causes a decreased partial pressure of arterial carbon dioxide (PaCO2). The decrease in PaCO2 increases the ratio of bicarbonate concentration to PaCO2 which increases the pH level. The decrease in PaCO2 develops when a strong respiratory stimulus causes the respiratory system to remove more carbon dioxide than is produced. Respiratory alkalosis can be acute or chronic. Acute respiratory alkalosis is when the PaCO2 level is below the lower limit of normal and the serum pH is alkalemic. Chronic respiratory alkalosis is when the PaCO2 level is below the lower limit of normal, but the pH level is relatively normal or near normal. Respiratory alkalosis is the most common acid-base abnormality observed in patients who are critically ill. It is associated with numerous illnesses and is a common finding in patients on mechanical ventilation. Many cardiac and pulmonary disorders can occur with respiratory alkalosis. When respiratory alkalosis is present, the cause may be a minor or non–life-threatening disorder. However, more serious disease processes should also be considered in the differential diagnosis (Byrd, 2017). Hyperventilation is most likely the underlying cause of respiratory alkalosis. Hyperventilation is also known as over breathing (O’Connell, 2017).
of the air spaces and drops the air pressure in the lungs so that air