| Question | Answer |
| upper respiratory system | nose, pharynx, and associated structures |
| lower respiratory system | larynx, trachea, bronchi, and lungs |
| conducting zone | conducts air to the lungs (nose, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles) |
| respiratory zone | site of gas exchange (respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli) |
| external nose | portion of nose visible on the face; bony framework and cartilaginous framework |
| function of the external nose (3) | warming, moistening, and filtering incoming air; detecting olfactory stimuli; modifying speech vibrations through the resonating chambers |
| resonance | prolonging, amplifying, or modifying a sound by vibration |
| internal nose | large cavity beyond nasal vestibule; ethmoid bone forms the roof; palatine bones and palatine processes of the maxillae form the floor |
| nasal septum | separates nasal cavity into right and left |
| what does the arrangement of superior, middle, and inferior meatus plus the conchae do? | increases surface area and prevents dehydration by trapping water during exhalation |
| location of the pharynx | starts at the internal nares and extends to the cricoid cartilage of the larynx |
| functions of the pharynx (3) | passageway for air and food; resonating chamber for speech; houses the tonsils |
| nasopharynx | houses pharyngeal (adenoid) tonsil; receives air from the nasal cavity along with packages of dust-laden mucus; exchanges small amounts of air with the auditory tubes to equalize air pressure between the pharynx and middle ear |
| oropharynx | contains one opening, fauces (throat); serves as a common passageway for air, food, and drink; houses the palatine and lingual tonsils |
| laryngopharynx (hypopharynx) | opens into the esophagus posteriorly (food); opens into the larynx anteriorly (voicebox) |
| larynx | small passageway connecting the laryngopharynx to the trachea |
| structure of larynx (9) | thyroid cartilage, epiglottis, cricoid cartilage, 2 arytenoid cartilage, 2 cuneiform cartilage, and 2 corniculate cartilage |
| arytenoid cartilages | influence changes in position and tension of the vocal cords (true vocal cords) |
| thyroid cartilage | Adam's apple |
| epiglottis | during swallowing elevation of the larynx causes the epiglottis to cover the glottis, this routes food and liquids into the esophagus |
| cricoid cartilage | hallmark for tracheotomies |
| cilia | move particles trapped in mucus down (upper respiratory) or up (lower respiratory) to the pharynx |
| pitch | controlled by tension on the vocal cords |
| vetnricular folds (false vocal cords) | formed by the larynx mucous membrane; when closed it functions in holding breath against pressure in the thoracic cavity |
| vocal folds (true vocal cords) | formed by the larynx mucous membrane; vibrate to produce sound with air |
| voice production | pharynx, mouth, nasal cavity, and paranasal sinuses act as resonating chambers; muscles of the face, tongue, and lips help enunciate the words |
| location of trachea | anterior to esophagus; below the larynx to T5, where it branches into right and left bronchi |
| structure of tracheal wall (4) | mucosa, submucosa, hyaline cartilage, and adventitia |
| 16-20 C-shaped rings of hyaline cartilage | open part faces the esophagus and provides support to the tracheal wall so it doesn't collapse inward during inhalation |
| right primary bronchus | more vertical, shorter, and wider than left; aspirated object more likely to lodge in the right |
| carina | where bronchi branches into left and right; most sensitive part of the cough reflex |
| bronchial tree | right/left primary bronchi > secondary (lobar) bronchi > tertiary (segmental) bronchi > bronchioles > terminal bronchioles |
| structural changes during branching (3) | mucous membrane changes; incomplete rings become plates then disappear; as cartilage decreases, the smooth muscle increases |
| asthma | because there is no supporting cartilage muscle spasms can occur closing off airways |
| pleural membrane | double-layered serous membrane: parietal pleura and visceral pleura |
| parietal pleura | lines the wall of the thoracic cavity |
| visceral pleura | covers the lungs themselves |
| base of the lungs | part resting on the diaphragm |
| apex of the lungs | top portion |
| hilus of the lungs | area where bronchi, pulmonary blood vessels, lymphatic vessels, and nerves enter/exit the lungs |
| cardiac notch | where the heart fits into the left lung |
| lobule | small compartments, containing: a lymphatic vessel, an arteriole, a venule, and a branch from a terminal bronchiole |
| respiratory bronchioles | sub branches of terminal bronchioles |
| alveoli | cup-shaped outpouching lined by simple squamous epithelium; two types of alveolar alveolar cells |
| alveolar sac | two or more alveoli that share the same opening |
| type I alveolar cells | most numerous; simple squamous; main site of gas exchange |
| type II alveolar cells | "septal cells;" cuboidal; contains microvilli and secretes alveolar fluid, keeps the surface between cells and air moist |
| surfactant | a mixture of phospholipids and lipoproteins within alveolar fluid; lowers surface tension which reduces the tendency of alveoli to collapse |
| alveolar macrophages (dust cells) | removes dust particles from alveolar spaces |
| structure of the respiratory membrane | alveolar and capillary walls; alveolar wall, epithelial basement membrane, capillary basement membrane, and capillary endothelium |
| function of the respiratory membrane | where exchange of carbon dioxide and oxygen occurs by diffusion |
| ventilation-perfusion coupling | vessels constrict to divert blood to better ventilated areas of the lung |
| respiration | process of gas exchange in the body |
| 3 steps of respiration | pulmonary ventilation, external (pulmonary) respiration, and internal (tissue) respiration |
| pulmonary ventilation | breathing; involves the exchange of air between the atmosphere and alveoli of the lungs |
| external (pulmonary) respiration | exchange of gases between alveoli of the lungs and blood in pulmonary capillaries; pulmonary capillary blood gains oxygen and loses carbon dioxide |
| internal (tissue) respiration | exchanges of gases between blood in systemic capillaries and tissue cells; blood loses oxygen and gains carbon dioxide (produced by cellular respiration) |
| Boyle's Law | pressure is inversely related to volume, more volume equals less pressure |
| inhalation | occurs when pressure in alveoli is less than atmospheric pressure (760mmHg); pressure change achieved by increasing the size of the lungs |
| diaphragm during inhalation | contracts causing it to flatten; responsible for 75% of the air entering the lungs |
| external intercostals during inhalation | contracts causing ribs to elevate allowing 25% of the air to enter the lungs |
| intrapleural (intrathoracic) pressure | pressure between two pleural layers; parietal pleura, visceral pleura and lungs are pulled in all directions |
| alveolar (intrapulmonic) pressure | pressure inside the lungs |
| accessory muscles | help increase the size of the thoracic cavity during forceful inhalation; sternocleidomastoid (elevates sternum), scalene (elevates first 2 ribs), and pectoralis minor (elevates ribs 3-5) |
| exhalation | passive process during quiet breathing |
| elastic recoil | cause of exhalation; two contributing forces: recoil of elastic fibers that were stretched during inhalation and inward pull of surface tension due to the film of alveolar fluid |
| muscles of forceful exhalation | abdominals and internal intercostals |
| alveolar surface tension | causes alveoli to assume the smallest possible diameter; surface tension must be overcome to expand lungs during inhalation; accounts for 2/3 of lung elastic recoil |
| lung compliance | high compliance means lungs and chest wall expand easily; two factors: elasticity and surface tension |
| airway resistance | larger diameter airway has less resistance; regulated by the diameter of bronchioles and smooth muscle tone |
| eupnea | normal quiet breathing |
| costal breathing | shallow breating, upward and outward movement |
| diaphragmatic breathing | deep breathing, outward movement of the abdomen |
| tidal volume | volume of air in one breath; approximately 500mL |
| minute ventilation | volume of air inhaled and exhaled each minute; (breaths per min) x (tidal volume) |
| spirometer | used to measure the volume of air exchanged during breathing and respiratory rate |
| inspiratory reserve volume (IRV) | additional air inhaled by taking a deep breath |
| expiratory reserve volume (ERV) | volume of air that can be exhaled in addition to tidal volume by exhaling forcefully |
| residual volume (RV) | air remaining after expiratory reserve volume is exhaled |
| inspiratory capacity (IC) | 3.6L; (tidal volume) + (inspiratory reserve volume); amount of air that can be inhaled |
| vital capacity (VC) | 4.8L; (IRV) + (tidal volume) + (ERV); amount of air inhaled and exhaled |
| functional residual capacity (FRC) | 2.4L; (ERV) + (RV); amount of air that can be exhaled |
| total lung capacity (TLC) | 6L; (VC) + (RV); total air |
| anatomic dead space | air in the conducting zone that does not undergo gas exchange |
| alveolar ventilation rate | volume of air per minute that reaches the respiratory zone |
| Dalton's Law | each gas exerts it's own pressure as if no other gases were present; each gas diffuses across a permeable membrane from the area where its partial pressure is greater to lower |
| Henry's Law | quantity of a gas that will dissolve in a liquid is proportional to the partial pressures of the gas and its soulbility; nitrogen gas normally doesn't dissolve into blood due to low solubility |
| nitrogen narcosis | under high pressure nitrogen gas enters blood |
| bends | nitrogen gas comes out of blood too quickly resulting in decompression sickness |
| external respiration (pulmonary gas exchange) | diffusion of oxygen from alveoli to blood in pulmonary capillaries and movement of carbon dioxide from the pulmonary capillaries to alveoli; occurs due to partial pressure differences and the exchange continues till partial pressures are equal |
| internal respiration | systemic capillaries exchange oxygen with tissue cells' carbon dioxide |
| partial pressure difference of the gases | alveolar partial pressure of oxygen must be higher than blood for diffusion to occur |
| surface area available for gas exchange | emphysema (alveolar wall disintegrates) lowers external respiration |
| diffusion distance | pulmonary edema (build up of IF between alveoli) greater the distance of diffusion slows gas exchange |
| molecular weight and solubility of gases | carbon dioxide has a 24x's solubility of oxygen; when diffusion is slow hypoxia occurs before hypercapnia |
| oxygen transport | 98.5% is bound to hemoglobin; 4 molecules of oxygen is bound to each globin (called oxyhemoglobin) |
| relationship between hemoglobin and partial pressure of oxygen | the higher the pressure the more oxygen will bind to hemoglobin |
| temperature's influence on Hb's affinity | when the temperature increases, more oxygen is released; a high temperature shifts the curve right |
| pH's influence on Hb's affinity | when acidity increases Hb's affinity for oxygen decreases, releasing oxygen; greater the acidity shifts the curve right |
| partial pressure of carbon dioxide on Hb's affinity | when partial pressure of carbon dioxide increases Hb's affinity for oxygen decreases; higher partial pressure of carbon dioxide shifts the curve right |
| BPG's influence on Hb's affinity | when BPG is high it increases the unloading of oxygen; high BPG shifts the curve right |
| 2,3-biphosphoglycerate (BPG) | formed in RBCs when they breakdown glucose for ATP |
| Hb affinity of fetal and adult hemoglobin | fetal Hb affinity higher than adult, therefore more oxygen from the mother's blood is transferred to fetal blood |
| carbon dioxide transport | 100mL of deoxygenated blood contains 53mL of gaseous carbon dioxide |
| dissolved carbon dioxide | only 7%, found in blood plasma; diffuses into alveolar air |
| carbamino compounds | 23% combines with amino groups of amino acids and proteins; carbaminohemoglobin |
| bicarbonate ions | 70% transported in blood; carbonic acid dissociates into hydrogen ion and bicarbonate (caused by carbonic anhydrase) |
| chloride shift | bicarbonate accumulates in RBCs as it picks up carbon dioxide causing an inflow of chloride ions to RBCs to balance the loss of negative ions |
| haldane effect | the lower amount of oxyhemoglobin the higher the carbon dioxide carrying capacity; deoxyhemoglobin buffers more hydrogen ion than oxyhemoglobin |
| respiratory center (3) | medullary rhythmicity in the medulla oblongata, pneumotaxic area in the pons, and apneustic area in the pons |
| medullary rhythmicity | nerve impulses in the inspiratory area establishes the rhythm of breathing; after 2 secs the inspiratory area inactivates and for 3 secs exhalation occurs; forceful breathing the expiratory area is activated |
| pneumotaxic area | transmits inhibitory impulses to the inspiratory area; turns off area before lungs become too full (shortens inhalation) |
| apneustic area | transmits excitatory impulses to the inspiratory area; prolongs inhalation for deep inhalation |
| cortical influence on respiration | voluntary control |
| chemoreceptor regulation of respiration | monitors levels of carbon dioxide, hydrogen ion, and oxygen; modes how quickly and how deeply we breathe |
| central chemoreceptors | located near the medulla oblongata and responds to changes in hydrogen ion concentration and partial pressure of carbon dioxide in CSF |
| peripheral chemoreceptors | located in the aortic bodies and in carotid bodies and monitor changes in partial pressure of oxygen and partial pressure of carbon dioxide and hydrogen ion in blood |
| proprioceptor stimulation | located in joints; when you start exercising proprioceptors stimulate the inspiratory area |
| inflation (Hering-Bruer) reflex | located in the walls of bronchi and bronchioles; inhibit inspiratory and apneustic areas by stimulating the vagus (X) nerves; protective mechanism preventing excessive inflation of the lungs |
| exercise and the respiratory system | as cardiac output rises, blood flow to the lungs is increased, and oxygen diffusion is increased |
| pulmonary perfusion | blood flow to the lungs |
