In contrast, the parietal pleura is the outer layer that connects to the thoracic wall, the mediastinum, and the diaphragm.Tags: Business Plan For A BakeryConcept EssaysOrchestra EssayFine Writing Paper StationeryEssay About Armenian GenocideBarn Burning By William Faulkner Point Of ViewCharacter Development EssayPolitical Essay QuestionsPoverty And In Africa EssayHow To Write A Brilliant Essay
As they near the alveoli, the pulmonary arteries become the pulmonary capillary network.
The pulmonary capillary network consists of tiny vessels with very thin walls that lack smooth muscle fibers.
This blood supply contains deoxygenated blood and travels to the lungs where erythrocytes, also known as red blood cells, pick up oxygen to be transported to tissues throughout the body.
The pulmonary artery is an artery that arises from the pulmonary trunk and carries deoxygenated, arterial blood to the alveoli.
In addition, innervation by the both the parasympathetic and sympathetic nervous systems provides an important level of control through dilation and constriction of the airway.
The major function of the lungs is to perform gas exchange, which requires blood from the pulmonary circulation.The parasympathetic system causes bronchoconstriction, whereas the sympathetic nervous system stimulates bronchodilation.Reflexes such as coughing, and the ability of the lungs to regulate oxygen and carbon dioxide levels, also result from this autonomic nervous system control.The pleura (plural = pleurae) is a serous membrane that surrounds the lung.The right and left pleurae, which enclose the right and left lungs, respectively, are separated by the mediastinum. The visceral pleura is the layer that is superficial to the lungs, and extends into and lines the lung fissures (Figure 2).A pulmonary lobule is a subdivision formed as the bronchi branch into bronchioles.Each lobule receives its own large bronchiole that has multiple branches.The right lung is shorter and wider than the left lung, and the left lung occupies a smaller volume than the right.The cardiac notch is an indentation on the surface of the left lung, and it allows space for the heart (Figure 1). Each lung is composed of smaller units called lobes. The right lung consists of three lobes: the superior, middle, and inferior lobes.Once the blood is oxygenated, it drains from the alveoli by way of multiple pulmonary veins, which exit the lungs through the hilum.Dilation and constriction of the airway are achieved through nervous control by the parasympathetic and sympathetic nervous systems.