XIIV Glossary
Alveoli: Small, grape-like air sacs surrounded by pulmonary blood capillaries. (Chapter 13.3)
Asthma: A common chronic respiratory disease characterized by episodes of bronchospasms (constriction of the bronchioles), inflammation, and edema of the airway that makes it difficult to exhale air. (Chapter 13.5)
Atelectasis: Occurs when alveoli lose air and collapse. (Chapter 13.5)
Bicarbonate: The majority of carbon dioxide (about 75%) is transported in the blood as bicarbonate (HCO3–) ions. (Chapter 13.4)
Bronchial tree: The collective term used for multiple-branched bronchial tubes. (Chapter 13.3)
Bronchioles: Small airways about 1 mm in diameter that branch extensively and lead to terminal bronchioles and alveoli, where gas exchange occurs. (Chapter 13.3)
Bronchospasms: Constriction of the bronchioles. (Chapter 13.5)
Carbaminohemoglobin: A compound formed when carbon dioxide binds to hemoglobin in red blood cells, accounting for about 20% of CO2 transport in the blood. (Chapter 13.4)
Carbon monoxide poisoning: Occurs when carbon monoxide (CO) builds up in the blood and can lead to serious tissue damage or death. (Chapter 13.5)
Cardiac notch: An indentation on the surface of the left lung that allows space for the heart. (Chapter 13.3)
Carina: A raised structure that contains specialized nervous tissue that causes violent coughing if a foreign body, such as food, is present. (Chapter 13.3)
Chronic obstructive pulmonary disease (COPD): A chronic, progressive lung disease caused by inflammation inside the airways, resulting in limited airflow out of the lungs; known as obstruction. (Chapter 13.5)
Cilia: Short, hair-like projections from the cell surface that are involved in movement of the cell or the movement of substances along the cell surface. (Chapter 13.3)
Conducting zone: The parts of the respiratory system that air passes through but do not participate directly in gas exchange. (Chapter 13.2)
Coronavirus disease (COVID-19): An infectious respiratory disease caused by the SARS-CoV-2 virus. (Chapter 13.5)
Cystic fibrosis (CF): A genetic condition that alters a protein in the body involved in the function of the cells, tissues, and glands responsible for producing mucus and sweat. (Chapter 13.5)
Dissolved in plasma: About 5% of carbon dioxide is transported directly in the blood plasma and diffuses into the alveoli for exhalation. (Chapter 13.4)
Epiglottis: A flap of cartilage that closes over the windpipe during swallowing to prevent food and liquids from entering the airway. (Chapter 13.3)
Exhalation: Movement of air out of the lungs; also called expiration. (Chapter 13.4)
Expiratory reserve volume (ERV): The extra amount of air that can be forcibly exhaled after a normal exhalation, about 12 mL. (Chapter 13.4)
External respiration: The exchange of gases between the alveoli and pulmonary capillaries. (Chapter 13.4)
Influenza: A viral infection that affects the epithelial cells lining the respiratory tract; commonly called “the flu.” (Chapter 13.5)
Inhalation: The movement of air into the lungs; also called inspiration. (Chapter 13.4)
Inspiratory reserve volume (IRV): The extra volume of air that can be forcibly inhaled after a normal inhalation, about 3,100 mL. (Chapter 13.4)
Internal nares: The openings between the nasal cavity and the nasopharynx. (Chapter 13.3)
Internal respiration: The exchange of gases between the systemic capillaries and the tissues. (Chapter 13.4)
Larynx: A cartilaginous structure that connects the pharynx to the trachea and helps regulate the volume of air that enters and leaves the lungs; also known as the voice box. (Chapter 13.3)
Laryngopharynx: The lower part of the throat that directs air to the voice box and food to the swallowing tube, serving as a pathway for both respiration and digestion; also known as the hypopharynx. (Chapter 13.3)
Lung cancer: The leading cause of cancer death in both men and women. (Chapter 13.5)
Lungs: A pair of pyramid-shaped organs connected to the trachea by the right and left primary bronchi. (Chapter 13.3)
Lung volume: A medical term used for various volumes of air moved by the lungs at a given point of the respiratory cycle. (Chapter 13.4)
Nares: Allow air into the nasal cavity. (Chapter 13.3)
Nasal conchae: Three bony projections on each lateral wall of the nasal cavity that increase surface area and create turbulence, helping warm, humidify, and filter incoming air. (Chapter 13.3)
Nasopharynx: The upper section of the throat behind the nasal cavity that allows air to pass from the nose to the lungs. (Chapter 13.3)
Oropharynx: The middle section of the throat located behind the mouth that serves as a passageway for both food and air. (Chapter 13.3)
Oxyhemoglobin (HbO2): A bright, red-colored molecule that contributes to the bright red color of oxygenated blood. (Chapter 13.4)
Paranasal sinuses: Air-filled spaces in the bones surrounding the nasal cavity that help warm and humidify incoming air. (Chapter 13.3)
Pharyngitis: Inflammation of the pharynx or throat. (Chapter 13.5)
Pharynx: Involved in both digestion and respiration, receiving food and air from the mouth and air from the nasal cavity. (Chapter 13.3)
Pleural cavity: The space between the visceral and parietal layers that contains pleural fluid. (Chapter 13.3)
Pleural fluid: Secreted by both lung pleural layers and acts to lubricate their surfaces, which reduces friction between the two layers. (Chapter 13.3)
Pleuritis (Pleurisy): Inflammation of the pleura, the membranes surrounding the lungs and chest wall. (Chapter 13.5)
Pneumonia: An infection that inflames the alveoli, causing them to fill with fluid or pus. (Chapter 13.5)
Pneumothorax: Occurs when air leaks into the space between the lung and the chest wall, causing the lung to collapse. (Chapter 13.5)
Pulmonary edema: A serious condition where fluid accumulates in the lungs, making it difficult to breathe. (Chapter 13.5)
Pulmonary embolism (PE): A blood clot or other substance, such as fat or an air bubble, that has traveled through the bloodstream and lodged in a smaller vessel within the pulmonary circulation in the lungs and obstructed blood flow. (Chapter 13.5)
Pulmonary surfactant: A slippery fluid that reduces the surface tension of the alveoli and prevents them from collapsing. (Chapter 13.3)
Pulmonary ventilation: The act of breathing. (Chapter 13.4)
Pulmonologist: A physician who specializes in diagnosing and treating respiratory system diseases. (Chapter 13.6)
Pulmonology: The study of the lungs and their functions. (Chapter 13.1)
Residual volume (RV): The air left in the lungs after exhaling as much air as possible, averaging about 1,200 mL. (Chapter 13.4)
Respiratory distress syndrome (RDS): A condition that primarily affects premature babies, causing difficulty breathing. (Chapter 13.5)
Respiratory membrane: A thin barrier formed by alveolar and capillary walls that allows efficient gas exchange by simple diffusion of oxygen and carbon dioxide. (Chapter 13.3)
Respiratory rate: The total number of breaths that occur each minute. (Chapter 13.4)
Respiratory therapists (RTs): Health care professionals who monitor, assess, and treat people who are having problems breathing. (Chapter 13.6)
Respiratory zone: The parts of the respiratory system where gas exchange between air and blood occurs. (Chapter 13.2)
Sleep apnea: Chronic disorder that can occur in children or adults and is characterized by the cessation of breathing during sleep for several seconds. (Chapter 13.5)
Sudden infant death syndrome (SIDS): Sudden and unexplained death of a baby younger than one year old who otherwise appears healthy. (Chapter 13.5)
Thoracic surgeon: A surgeon who has specialized in either thoracic (chest) surgery or cardiothoracic (heart and chest) surgery. (Chapter 13.6)
Tidal volume (TV): The amount of air inhaled or exhaled in a normal quiet breath, which averages about 500 milliliters (mL) for a healthy male adult and 400 mL for a healthy female adult. (Chapter 13.4)
Tonsillitis: Inflammation of the tonsils (Chapter 13.5)
Total lung capacity (TLC): The sum of all lung volumes (TV+ ERV+ IRV+ RV), which represents the total amount of air a person can hold in their lungs after a forceful inhalation. (Chapter 13.4)
Trachea: An approximately 5-inch-long tubular airway that extends from the larynx inferiorly toward the lungs; also called the windpipe. (Chapter 13.3)
True vocal cords: A pair of white, membranous ligaments attached to cartilage pieces of the larynx; also called vocal folds. (Chapter 13.3)
Tuberculosis (TB): A potentially fatal infectious disease, primarily affecting the lungs but capable of spreading to other organs; caused by Mycobacterium tuberculosis in most U.S. cases. (Chapter 13.5)
Upper respiratory tract infection (URI): The swelling and irritation of the upper airways, including the nose, sinuses, throat, larynx, and larger airways; known as the common cold. (Chapter 13.5)
Uvula: Small, conical projection that hangs from the posterior edge of the soft palate and helps prevent food from entering the nasal cavity during swallowing. (Chapter 13.3)
Vital capacity (VC): The amount of air a person can move into or out of their lungs, which is the sum of all volumes except residual volume (TV+ ERV+ IRV) and is between 4,000 and 5,000 milliliters for adults. (Chapter 13.4)