Air enters the lungs via the "trunk", the trachea. The trachea branches in two, to form the bronchi. Each bronchus continues to branch out each branch is a different colour in the image above until, at the end of each bronchiole, we reach a cluster of alveoli like grapes on the bough. Alveoli are small sacs where the gas-exchange of CO 2 and O 2 takes place. There is an intricate web of blood vessels which wrap around each sac, allowing the transfer of gases to take place through the extremely thin walls of the alveoli.
The total surface area of the alveoli is very, very large - roughly the size of a tennis court. The lungs are not equal in size. The right lung is shorter, because the liver sits high, tucked under the ribcase , but it is broader than the left.
The left lung is smaller because of the space taken up by the heart see diaphragm for an image of this. The alveoli have many capillary veins in their walls. Oxygen passes through the alveoli, into the capillaries and into the blood. It is carried to the heart and then pumped throughout the body to the tissues and organs.
As oxygen is going into the bloodstream, carbon dioxide passes from the blood into the alveoli and then makes its journey out of the body. This process is called gas exchange. When a person breathes shallowly, carbon dioxide accumulates inside the body. This accumulation causes yawning, according to York University. The lungs have a special way to protect themselves. Cilia, which look like a coating of very small hairs, line the bronchial tubes.
The cilia wave back and forth spreading mucus into the throat so that it can be dispelled by the body. Mucus cleans out the lungs and rids them of dust, germs and any other unwanted items that may end up in the lungs. The lungs can have a wide range of problems that can stem from genetics, bad habits, an unhealthy diet and viruses. Asthma , also called reactive airway disease before a diagnosis of asthma, is a lung disease where the air passageways in the lungs become inflamed and narrowed, making it hard to breath.
In the United States, more than 25 million people, including 7 million children, have asthma, according to the National Heart, Lung, and Blood Institute. Lung cancer is cancer that originates in the lungs. It is the No. Symptoms of cancer include coughing up blood, a cough that doesn't go away, shortness of breath, wheezing, chest pain, headaches, hoarseness, weight loss and bone pain.
Chronic obstructive pulmonary disease COPD is long-term lung disease that prevents a person from breathing properly due to excess mucus or the degeneration of the lungs. Chronic bronchitis and emphysema are considered COPD diseases. About Sometimes, those with COPD get lung transplants, replacement lungs garnered from organ donors, to save their lives.
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.
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