Location of human heart behind rib cage
The volume, the total capacity, and the weight of the right lung is greater than that of the left. The right lung is divided into three lobes. The upper lobe is the largest lobe of the right lung. It extends from the apex of the lung down to the horizontal and oblique fissures.
It bears apical, anterior, and posterior bronchopulmonary segments. The middle lobe is the smallest lobe of the right lung, located between the horizontal and oblique fissures. It bears medial and lateral bronchopulmonary segments. The lower lobe is the bottom lobe of the right lung.
It lies beneath the oblique fissure. It bears medial, lateral, superior, anterior, and posterior bronchopulmonary segments. The Left Lung : This has a concave depression that accommodates the shape of the heart, called the cardiac notch.
The human left lung is smaller and narrower that the right lung, and is divided into two lobes, an upper and a lower, by the oblique fissure. The left lung has only two formal lobes because of the space taken up in the left side of the chest cavity by the heart, though it does have the lingula, which is similar to a lobe. The left lung has a depression on the medial side of its surface called the cardiac notch, a concave impression molded to accommodate the shape of the heart.
The upper lobe of the left lung contains anterior and apicoposterior bronchopulmonary segments. It is above the oblique fissure. The lower lobe of the left lung contains superior, anterior, posterior, medial, and lateral bronchopulmonary segments. The lingula is not formally considered to be a lobe.
It is a small, tongue-like projection of the left lung that is analogous to the middle lobe of the right lung. It contains superior and inferior bronchopulmonary segments. Above and behind the cardiac impression is a triangular depression named the hilum. The hilum is the root of the lung where that contains structures that supply the lungs with blood, lymph fluid, and innervation, such as the pulmonary vein, pulmonary artery, pulmonary nerves, and lymphatic vessels.
These structures are enclosed by pleura. There is a hilium for each of the lungs found in the mediastinum backside of the lungs. The hilium is thinner in the left lung compared to the right lung because it lies between the cardiac notch and the groove for the aorta.
The hilium is important because it is the primary way in which the respiratory system links with the cardiovascular and nervous systems. Pulmonary circulation transports oxygen-depleted blood away from the heart to the lungs and returns oxygenated blood back to the heart. Bronchial circulation by the bronchial arteries supplies blood to the tissues of the bronchi and the pleura, and is considered part of systemic circulation. The right side of the heart deals with pulmonary circulation.
At the end of systemic circulation, the veins take blood back to the heart through the vena cava. The vena cava fills the right atrium with blood, which then ejects blood into the right ventricle by passing through the tricuspid valve. After blood fills in the right ventricle, it contracts and pumps the blood through the pulmonary valve, and into the pulmonary arteries. There are two pulmonary arteries one for each lung that bring the deoxygenated blood to the lungs through the hilium. The arteries branch into the capillaries of the alveoli. Capillaries are the thinnest and smallest type of blood vessel, and they supply oxygen to individual tissues everywhere in the human body.
Gas exchange occurs by passive diffusion in the alveoli, so that dissolved oxygen enters the capillaries, while carbon dioxide leaves pulmonary circulation. The oxygenated blood then leaves the lungs through pulmonary veins also contained in the hilium , which return the blood to the left side of the heart, completing the cycle of pulmonary circulation.
This blood then enters and fills inside the left atrium, which pumps it through the mitral valve also called bicuspid into the left ventricle. The blood fills inside the left ventricle and is then pumped through the aortic valve into the aorta, which marks the beginning of systemic circulation.
Systemic circulation and pulmonary circulation form the overall cycle of the circulatory system: transporting oxygen throughout the body. Pulmonary circuit : Diagram of pulmonary circulation. Oxygen-rich blood is shown in red; oxygen-depleted blood in blue. The heart valves work the same way as one-way valves in the plumbing of your home, preventing blood from flowing in the wrong direction. Each valve has a set of flaps, called leaflets or cusps. The mitral valve has two leaflets; the others have three. The leaflets are attached to and supported by a ring of tough, fibrous tissue called the annulus.
The annulus helps to maintain the proper shape of the valve.
The human ribcage
The leaflets of the mitral and tricuspid valve are also supported by tough, fibrous strings called chordae tendineae. These are similar to the strings supporting a parachute. The chordae tendineae extend from the valve leaflets to small muscles, called papillary muscles, which are part of the inside walls of the ventricles.
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Your Heart & Blood Vessels | Cleveland Clinic
We do not endorse non-Cleveland Clinic products or services. Primary tumors originate in the bone or muscle of the chest wall.
Less than half of malignant chest wall tumors are primary. Secondary tumors originate elsewhere in the body and spread metastasize to the chest wall. Almost all secondary tumors are malignant. Most chest wall tumors found in children are primary, while most found in adults are secondary. All of these tumors tend to be a lump on the chest wall surface or a growth that invades the bone or muscle. While hereditary factors, diet and lifestyle choices may play a role in certain tumor types, there are no clear causes of chest wall tumors.
Chest Wall Tumors The chest cavity is a cage that is framed by the sternum breastplate , spine and ribs. Schedule An Appointment. Conditions Chest Wall Tumors. Like any other part of the body, the walls of the chest cavity are susceptible to tumors.
A tumor is any type of abnormal growth of cells, whether malignant cancerous or benign non-cancerous. Chest wall tumors can interfere with pulmonary function. Symptoms Risk Factors Diagnosis Treatment. Symptoms of benign chest wall tumors may include one or more of the following: A localized mass Swelling Chest Pain Muscle atrophy breakdown Symptoms of malignant chest wall tumors may include one or more of the following: A localized mass Swelling Chest Pain Impaired movement or chest expansion.