Term
|
Definition
| Gas exchange between atmosphere, blood, and cells. |
|
|
Term
| What is pulmonary ventilation? |
|
Definition
| The movement of air into and out of lungs, breathing. |
|
|
Term
| What is external respiration? |
|
Definition
| Gas exchange between blood and the lungs. |
|
|
Term
| What is internal respiration? |
|
Definition
| The gas exchange between blood and tissue in the body. |
|
|
Term
| What is the function of pleural fluid? |
|
Definition
| Allows lungs to slide within thorax during breathing, separation between pleurae creates surface tensions so lungs cling to thoracic wall. |
|
|
Term
|
Definition
| From the diaphragm to slightly superior of clavicles. |
|
|
Term
| What is the general anatomy of the right lung? |
|
Definition
| 3 lobes (superior, middle, and inferior), with an oblique and horizontal fissure. |
|
|
Term
| What is the general anatomy of the left lung? |
|
Definition
| 2 lobes (superior and inferior), with one oblique fissure and a depression for the heart. |
|
|
Term
| What is the ordering of bronchi? |
|
Definition
| Primary, secondary, and tertiary (segmental). |
|
|
Term
| Each segmental bronchi supplies how many of what? |
|
Definition
| Bronchopulmonary segments (about 10), which contain many small lobule compartments - the smallest visible unit. |
|
|
Term
|
Definition
| Small sacs where gas exchange occurs, surrounded by elastic fibers. |
|
|
Term
|
Definition
|
|
Term
| What engulfs pathogens in the lungs? |
|
Definition
| Alveolar macrophages, dust cells. |
|
|
Term
| What are type I cells in the lungs? |
|
Definition
| Simple squamous endothelial cells of the alveoli. |
|
|
Term
| What does the respiratory membrane allow for? |
|
Definition
| Gas exchange between air on the alveolar side, and blood on the capillary side. |
|
|
Term
| What are type II cells in the respiratory cells? |
|
Definition
| Cuboidal cells that secrete fluid (surfactant) which prevents collapse of alveoli during expiration. |
|
|
Term
| What are the two phases of pulmonary ventilation? |
|
Definition
| Inspiration and expiration. |
|
|
Term
| What is intrapulmonary pressure? |
|
Definition
| Pressure within the alveoli, rises and falls with breathing, but always equalizes with atmospheric pressure. |
|
|
Term
| What is intrapleural pressure? |
|
Definition
| The pressure within the pleural cavity, fluctuates with breathing but ALWAYS ~ 4 mmHg less than alveolar pressure. |
|
|
Term
| Why is the intrapleural pressure always less than alveolar pressure? |
|
Definition
| Because of the natural elasticity of lungs and their tendency to recoil to smallest size, surface tension of alveolar fluid that draws alveoli into smallest position. |
|
|
Term
| What is transpulmonary pressure? |
|
Definition
| The difference between intrapulmonary and intrapleural pressure, keeps the lungs from collapsing. |
|
|
Term
| What is the technical term for a collapsed lung? |
|
Definition
|
|
Term
| What are the two steps of inspiration? |
|
Definition
| The diaphragm contracts, followed by intercostal muscles which lift rib cage and sternum to expand thoracic volume even more. |
|
|
Term
| What other muscles become involved during forced inspiration? |
|
Definition
| Sternocleidomastoid, scalenes, and pectoralis minor all act to increase thoracic volume. |
|
|
Term
| What muscles aid in forced expiration? |
|
Definition
| Obliques and transversus abdominis, as well as internal intercostals. |
|
|
Term
| What must alveolar overcome in order to expand? |
|
Definition
| Surface tension within them. Surfactant is a mixture of lips and proteins that reduces surface tension. |
|
|
Term
| What occurs in infant respiratory distress syndrome? |
|
Definition
| Too little surfactant, requires ventilation and surfactant replacement. |
|
|
Term
| What is compliance of the lungs? |
|
Definition
| Distensibility, the ease with which lungs and thoracic wall expand. |
|
|
Term
|
Definition
| A mixture of gases in contact with a liquid will dissolve in such a way that it is proportionate to its partial pressures. |
|
|
Term
| What is the most soluble gas? |
|
Definition
|
|
Term
| What is an insoluble gas? |
|
Definition
|
|
Term
| What is nitrogen narcosis? |
|
Definition
| N2 accumulation in lipids, esp. the CNS fatty tissue - causes dizziness. |
|
|
Term
| CO2 is how many times more soluble than O2 in the blood? |
|
Definition
| 20 times more soluble than O2 |
|
|
Term
| What occurs in a high alveolar O2? |
|
Definition
| Arterioles dilate to increase uptake of O2. |
|
|
Term
| At rest how much of available oxygen from blood enters cells? |
|
Definition
| About 25 % enters tissue cells. |
|
|
Term
| What happens to hemoglobin as the pressure of O2 is increased? |
|
Definition
| It is loaded with oxygen until its maximum potential is reached. |
|
|
Term
| What factors effect hemoglobin's affinity for O2? |
|
Definition
| Increased temperature, H+ content, and pressure of CO2. |
|
|
Term
| What occurs in an acidic environment? |
|
Definition
| The Bohr shift - O2 readily splits from hemoglobin because a decreased pH weakens O2-Hemoglobin bond. |
|
|
Term
| What happens to hemoglobin as temperature is increased? |
|
Definition
| The amount of O2 released from hemoglobin increases. |
|
|
Term
| What is the problem with CO and hemoglobin? |
|
Definition
| It's affinity for hemoglobin is 200x stronger than oxygen's - can severely reduce oxygen carrying capacity of the protein. |
|
|
Term
| How is CO2 transported in blood? |
|
Definition
| Dissolved in plasma (least), carbaminohemoglobin (bound to globin, middle), and bicarbonate ions which dissociate into H+ and HC03- (most of all). |
|
|
Term
| What happens as CO2 is converted to bicarbonate? |
|
Definition
| The chloride shift, as HCO3 leaves Cl enters RBC's, maintaining ionic balance between plasma and RBC |
|
|
Term
| What happens as CO2 enters the blood? |
|
Definition
| Causes O2 to split from hemoglobin, lowers blood pH as H+ increases. |
|
|
Term
| What happens as O2 binds to hemoglobin with respect to CO2? |
|
Definition
| CO2 is released from the blood. |
|
|
Term
| Where is the respiratory center of the brain? |
|
Definition
| In the reticular formation of the medulla and pons. |
|
|
Term
| What is the inspiration pacesetter? |
|
Definition
| The dorsal respiratory group. |
|
|
Term
| What suppresses the medullary respiratory center? |
|
Definition
| Sleeping pills, alcohol, and morphine, supress this center. |
|
|
Term
| What are expiratory area neurons? |
|
Definition
| Inactive during most quiet respiration, activated during high ventilation, causes contraction of forced expiration muscles. |
|
|
Term
| What is the ventral respiratory center responsible for? |
|
Definition
|
|
Term
| What are the pons respiratory centers responsible for? |
|
Definition
| Smoothing transitions between inspiration and expiration, fine tuning of rhythm. |
|
|
Term
| What is the pneumotaxic center? |
|
Definition
| Inhibits medullary inspiratory center to prevent lung overinflation. |
|
|
Term
| What is the apneustic center? |
|
Definition
| Stimulates medullary inspiratory center to prolong inspiration. |
|
|
Term
| How does chemical regulation occur to regulate H+, CO2, and O2 levels in arterial blood? |
|
Definition
| Central chemoreceptors (medulla), and peripheral chemoreceptors (aortic arch and carotid arteries) |
|
|
Term
| What are central chemoreceptors? |
|
Definition
| Respond to changes in H+ / pressure of CO2 in CSF. |
|
|
Term
|
Definition
| CSF pH decreased, stimulates respiratory center. |
|
|
Term
| What are peripheral chemoreceptors? |
|
Definition
| Respond to changes in O2 pressure in arteries. |
|
|
Term
| What is the most important stimulus for breathing in a healthy person? |
|
Definition
|
|
Term
| What happens if the pressure of CO2 is too low? |
|
Definition
| Hypocapnia, CO2 must accumulate to trigger respiration. |
|
|
Term
| What is a long term adjustment to high altitude? |
|
Definition
| Kidneys produce more erythropoietin to stimulate RBC production. |
|
|
Term
|
Definition
| Alveoli lose elasticity, causes lung fibrosis. |
|
|
