Volumes: lung volumes - vital capacity - functional residual capacity - respiratory minute volume - dead space - spirometry - body plethysmography - peak flow meter The Respiratory System Among four-legged animals, the respiratory system generally includes tubes, such as the bronchi, used to carry air to the lungs, where gas exchange takes place. ... Human physiology is the science of the mechanical, physical, and biochemical functions of normal humans or human tissues or organs. ... It has been suggested that Gas exchange be merged into this article or section. ... The average pair of human lungs can hold about 6 litres of air, but only a small amount of this capacity is used during normal breathing. ... Vital capacity is the total amount of air that a person can expire after a complete inspiration. ... Functional Residual Capacity (FRC) is a medical term referring to the amount of air present in the lungs at the end of passive expiration. ... In physiology, dead space is air that is inhaled by the body in breathing, but does not partake in gas exchange. ... Spirometry (meaning the measuring of breath) is the most common of the Pulmonary Function Tests (PFTs), measuring lung function, specifically the measurement of the amount (volume) and/or speed (flow) of air that can be inhaled and exhaled. ... Body Plethysmographs-To do a body plethysomograph, the person is enclosed in an airtight chamber often referred to as a body box. ... A peak flow meter is a small, hand-held device used to manage asthma by monitoring airflow through the bronchi and thus the degree of restriction in the airways. ...

ventilation (V) (positive pressure) breath (inhalation, exhalation) - respiratory rate - respirometer - pulmonary surfactant - compliance - hysteresivity - airway resistance In respiratory physiology, ventilation is the rate at which gas enters or leaves the lung. ... Positive Pressure ventilators help patients with respiratory problems to breathe easier. ... Breathing redirects here. ... Exhalation is the movement of air out of the bronchial tubes, through the airways, to the external environment during breathing. ... It has been suggested that this article or section be merged with Minute volume. ... ... Diagram of the alveoli with both cross-section and external view Pulmonary surfactant is a surface-active lipoprotein formed by type II alveolar cells. ... “Hysteresivity” derives from “hysteresis”, meaning “lag”. It is the tendency to react slowly to an outside force, or to not return completely to its original state. ... Airway resistance is a concept used in respiratory physiology to describe mechanical factors which limit the access of inspired air to the pulmonary alveoli, and thus determine airflow. ...

pulmonary circulation - perfusion (Q) - hypoxic pulmonary vasoconstriction - pulmonary shunt Pulmonary circulation is the portion of the cardiovascular system which carries oxygen-depleted blood away from the heart, to the lungs, and returns oxygenated blood back to the heart. ... Perfusion is a physiological term that refers to the process of nutritive delivery of arterial blood to a capillary bed in the biological tissue. ... Hypoxic Pulmonary Vasoconstriction is the phenomenon when pulmonary arterioles vasoconstrict in the presence of hypoxia (low oxygen levels) without hypercapnia (high carbon dioxide levels). ...

ventilation/perfusion ratio (V/Q) and scan - zones of the lung - gas exchange - pulmonary gas pressures - alveolar gas equation - hemoglobin - oxygen-haemoglobin dissociation curve (DPG, Bohr effect, Haldane effect) - carbonic anhydrase - oxyhemoglobin - respiratory quotient - arterial blood gas - diffusion capacity - Dlco In respiratory physiology, the ventilation/perfusion ratio (or V/Q ratio) is a measurement used to the efficiency and adequacy of the matching of two variables:[1] V - ventilation - the air which reaches the lungs Q - perfusion - the blood which reaches the lungs A normal value is approximately 0. ... Gas exchange or respiration takes place at a respiratory surface - a boundary between the external environment and the interior of the body. ... 3-dimensional structure of hemoglobin. ... The oxygen-haemoglobin dissociation curve plots the proportion of haemoglobin in its saturated form on the vertical axis against the prevailing oxygen tension on the horizontal axis. ... 2,3-bisphosphoglycerate (2,3-BPG, also known as 2,3-diphosphoglycerate or 2,3-DPG) is a three carbon isomer of the glycolytic intermediate 1,3-bisphosphoglycerate and is present at high levels in the human red blood cell (RBC; erythrocyte) in the same molar concentration as hemoglobin. ... The Bohr effect is an adaption in animals to reduce the affinity of hemoglobin for oxygen as a response to an increase in blood carbon dioxide levels and a decrease in pH. It was first described by the Danish physiologist Christian Bohr in 1904. ... The Haldane effect is a property of hemoglobin first described by the British physician John Scott Haldane. ... Carbonic anhydrase (carbonate dehydratase) is a family of metalloenzymes (enzymes that contain one or more metal atoms as a functional component of the enzyme) that catalyze the rapid interconversion of carbon dioxide and water into carbonic acid, protons, and bicarbonate ions. ... The Respiratory Quotient is used in BMR calculations (basal metabolic rate) and is a form of indirect calorimetry. ... Arterial blood gas measurement is a blood test that is performed to determine the concentration of oxygen, carbon dioxide and bicarbonate, as well as the pH, in the blood. ... In biology, diffusion capacity is a measurement of the lungs ability to absorb and excrete gases, notably, oxygen and carbon dioxide. ... There are very few or no other articles that link to this one. ...

control of respiration: pons (pneumotaxic center, apneustic center) - medulla (dorsal respiratory group, ventral respiratory group) - chemoreceptors (central, peripheral) - pulmonary stretch receptors - Hering-Breuer reflex Control of ventilation refers to the physiological mechanisms involved in the control of ventilation (physiology). ... Position of the pons in the human brain The pons (sometimes pons Varolii after Costanzo Varolio) is a knob on the brain stem. ... The medulla oblongata is the lower portion of the brainstem. ... The dorsal repiratory group is found in many types of fish and marine mammals. ... A Chemosensor, also known as chemoreceptor, is a cell or group of cells that transduce a chemical signal into an action potential. ...

high altitude - oxygen toxicity - hypoxia Oxygen toxicity or oxygen toxicity syndrome is severe hyperoxia caused by breathing oxygen at elevated partial pressures. ... Hypoxia is a pathological condition in which the body as a whole (generalised hypoxia) or region of the body (tissue hypoxia) is deprived of adequate oxygen supply. ...