| Question | Answer |
| Respratory Zone | site of gas exchange, consists of bronchioles, alveolar ducts and alveoli |
| Conducting Zone | conduits for air to reach the sites of gas exchange, includes nose, nasal cavity pharynx, trachea |
| major funcions of respiratory system | to supply the body with oxygen and dispose of carbon dioxide |
| respiration | four distinct processes must happen |
| pulmonary ventilation | moving air into and out of the lungs |
| external repiration | gas exchane between the lungs and the blood |
| transport | transport of oxygen and carbon dioxide between the lungs and tissues; lungs |
| internal respiration | gas exchange between systemic blood vessels and tissues; tissues |
| functions of the nose | only externally visible part of repiratory system functions by:
providing an airway fro respiration
mostening/warming the entering air
filtering air and cleaing it of foreign matter
serving as resonating chamber for speech
housinng olfactory receptor |
| inspired air | humidified by the high water content in the nasal cavity
warmed by rich plexuses of capillaries |
| ciliated mucosal cells | remove contaminated mucus |
| pharynx | funnel-shaped tube of skeletal muscle that connects to the:
nasal cavity and mouth superiorly
larynx and esophagus inferiorly
-goes from base of skull to the level of the 6th vervical vertebra |
| pharynx divided in to 3 regions | nasopharynx, oropharynx, laryngopharynx |
| nasopharynx about | lies posterior to the nasal cavity, inferior to the sphenoid, and superior to the level of the soft palate
strictly an air passageway
lined with pseudostartified columnar epithelium |
| nasopharynx does | closes(by the uvula) during swallowing to prevent food from entering the nasal cavity
the pharyngeal tonsil lies high on the posterior wall
pharyngotympanic (auditory) tubes open into the lateral walls |
| oropharynx about | extends inferiorly from the level of the soft palate to the epiglottis
opens to the oral cavity via an archway called the fauces
serves as a common passageway for food and air |
| oropharynx does | the epithelial lining is prtective stratified squamous epithelium-reduces friction when swollowing
palatine tonsils lie in the lateral walls of the fauces
lingual tonsil covers the base of the tongue |
| laryngopharynx | serves as a common passage for food and air
lies posterior to the upright epiglottis(opening to the treachea)
extends to the laynx, where the repiratory and diestive pathways diverge |
| larynx (voice box) | attaches to the hyoid bone and opens into the larngopharynx superiorly
continuos with the trachea posteriorly
elastic cartilage |
| larynx (voice box) 3 functions | -to provide a patent airway
-to act as a switching mechanism to route air and food into the proper channels
-to function in voice production |
| framework of larynx | cartilages (hyaline) of the larynx:
-shield-shaped anterosuperior thyroid cartilage with a midline laryngeal prominence (adam's apple)
-signet ring-shaped anteroinferior cricoid cartilage
-3 pairs arytenoid,cuniform,corniculate cartilages |
| epiglottis | elastic cartilage that covers the laryngeal inlet during swallowing |
| vocal ligaments | attach the arytenoid cartilages to the thyroid cartilage
composed of elastic fibers that form mucosal folds called true vocal cords
-the medial opening between them is the glottis
-they vibrate to produce sounds as air rushes up from the lungs |
| vocal ligaments-false vocal cords | mucosal folds superior to the true vocal cords
have no part in sounds production
*false about true* |
| vocal production (speech) | intermittent release of expired air while opening and closing the glottis |
| vocal production (pitch) | determined by the length and tension of the vocal cords |
| vocal production (loudness) | depends upon the force at which the air rushes across the vocal cords |
| vocal production | the pharynx resonates, amlifies, and enhances sound quality
sound is "shaped" into language by action of the pharynx, tongue, soft palate, and lips
longer the cord the lower the pitch
grunts/words,are utterinces molded into fimilar pitches called langu |
| sphincter functions of the larynx | the larynx is closed during coughing, sneezing, and valsalva's maneuver |
| valsalva's maneuver | air is temporarily held in the lower reporatory tract by closing the glottis
causes intra-abdominal pressure to rise when abdominal muscles contract
helps empty rectum
acts as a splint to stabilize the trunk when lifting heavy loads |
| trachea | flexible and mobile tuve extending from the larynx into the mediastinum
3 layers: mucosa, submucosa, adventitia |
| trachea (mucosa) | made up of goblet cells and ciliated epithelium |
| trachea (submucosa) | connective tissue deep to the mucosa |
| trachea (adventitia) | outermost layer made of C-shaped rings of hyaline cartilage |
| bronchi | carina of the last tracheal cartilage marks the end of the trachea and the beginning of the bronchi
subdivide into secondary bronchi, each supplying a lobe of the lungs
air passages undergo 23 orders of branching |
| bronchial tree | tissue walls of bronchi mimic that of the trachea
as conducting tubes become smaller, structural changes occur:
-cartilage support structures change
-epithelium types change
-amount of smooth muscle increases |
| brochioles | consiste of cuboidal epithelium
have a complete layer of circular smooth muscle
lack cartilage support and mucus-producing cells |
| alveoli | begins as terminal bronchioles feed into respiratory bronchioles |
| respiratory bronchioles | lead to alveolar ducts, then to terminal clusters of alveolar sacs composed of alveoli |
| 300 million alveoli | account for most the lungs volume
provide tremendous surface area for gas exchange |
| respiratory membrane (air-blood barrier) | composed of:
-alveolar and capillary walls
-their fused basal laminas |
| alveolar walls | -are single layer of type 1 epithelial cells
-permit gas exchange by simple diffusion
-secrete angiotensin converting exzyme (ACE)
type 2 cells secrete surfactant |
| alveolar surface tension (surface tension) | the attraction of liquid molecules to one another at a liquid-gas interface
the liquid coating the alveolar surface is always acting to reduce the alveoli to the smallest possibble size |
| alveolar surface tension (surfactant) | a detergent-like complex, reduces surface tension and helps keep the alveoli from collapsing
without surfactant water in lungs will stick and colapse
surfactant keeps water from sticking |
| alveoli | surrounded by fine elastic fibers
contain open pores that:
-connect adjacent alveoli
-allow air pressure throughout the lung to be equalized
house macrophages that keep alveolar surfaces sterile |
| Pleurae (take out lungs and heart and paint inside) | thin, double-layered serosa
parietal pleura
-covers the thoaracic wall and superior face of the diaphragm
-continues around heart and between lungs |
| pleurae (paint heart&lungs different color, put back, 2 layers)(visceral, or pulmonary, pleura) | visceral, or pulmonary, pleura
-covers the external lung surface
-divides the thoracic cavity into 3 chambers
-the central mediastinum
-two lateral compartments, each containing a lung |
| breathing | breathing, or pulmonary ventilation, consists of two phases
-inspiration-air flows into the lungs
-expiration-gases exit the lungs |
| atmospheric pressure (P(atm)) | respiratory pressure is described relative to atomspheric pressure
pressure exerted by the air surrounding the body
negative respiratory pressure is less than P(atm)
positive respriatory pressure is greater than P(atm)
760 mm mercury |
| pressure relationships in the thoracic cavity (intrapulmonary pressure (P(pul)) | pressure within the alveoli |
| pressure relationships in the thoracic cavity (intrapleural pressure (P(ip)) | pressure within the pleural cavity |
| pressure relationships | intrapulmonary pressure and intrapleural pressure fluctuate with the phases of breathing
intrapulmonary pressure always eventually = itself with atmospheric pressure
intrapleual pressure is always less thena intrapulmonary pressure and atmopheric pressu |
| pressure relationships (2 forces) | two forces act to pull the lungs away from the thoaracic wall, promoting lung collapse
-elasticity of lungs causes them to assume smallest possible size
-surface tension of alveolar fluid draws alveoli to their smallest possible size |
| pressure relationships (opposing force) | elasticity of the chest wall pulls the thorax outward to enlarge the lungs
elasticity- strech and return |
| lung collapse | caused by equalization of the intrapleural pressure with the intrapulmonary pressure
transpulmonary pressure keeps the airways open |
| transpulmonary pressure | difference between the intrapulmonary and intrapleural pressures (P(pul)-P(ip))
when intrapleural punctured it brings in air |
| Boyle's Law | the relationship between the pressure and volume of gases P1V1=P2V2
P=pressure of a gas in mm Hg
V=volume of a gas in cubic millimeters
supscripts 1 and 2 represent the initial and resulting conditions, respectively
pressure goes up volume goes down |
| physical factors influencing ventilation:airway resistance | friction is the major nonelastic source of resistance to airflow
the relationship between flow (F) pressure (P) and resistance (R): F=(triangle)change in temp*P/R
pressure goes up flow goes up, resistance goes up flow goes down |
| lung compliance | ease with which lungs can be expanded
determinded by 2 factors
-distensibility of the lung tissue and surrounding thoracic cage
-surface tension of the alveoli
factors-scar tissue or fibrosis that reduces the natural resilience of the lungs |
| eplasmia | enought oxygen but not letting the CO2 out |
| exampes of diminish lung compliance | -deformities of thorax
-ossification of the costal cartilage
-paralysis of intercostal muscles |
| tidal volume (TV) | air that moves into and out of the lungs with each breath(normal breathing) |
| inspiratory reserve volume (IRV) | air that can be inspired forcibly beyound the tidal volume (pushing it out) |
| expiratory reserve volume (ERV) | air that can be evacuated from the lungs after a tidal expiration(deep inhale-exhale and grunt) |
| residual volume(RV) | air left in the lungs after strenuous expiration |
| inspiratory capacity (IC) | total amount of air that can be inspired after a tidal expiration ( |
| tidal volume (TV) | air that moves into and out of the lungs with each breath(normal breathing) |
| inspiratory reserve volume (IRV) | air that can be inspired forcibly beyound the tidal volume (pushing it out) |
| expiratory reserve volume (ERV) | air that can be evacuated from the lungs after a tidal expiration(deep inhale-exhale and grunt) |
| residual volume(RV) | air left in the lungs after strenuous expiration |
| inspiratory capacity (IC) | total amount of air that can be inspired after a tidal expiration (IRV+TV) |
| functional residual capacity (FRC) | amount of air remaining in the lungs after a tidal expiration (RV+ERV) |
| vital capacity(VC) | the total amount of exchangeable air (TV+IRV+ERV) |
| total lung capacity (TLC) | sum of all lung volumes |
| anatomical dead space | volume of the conducting repiratory passages |
| alveolar dead space | alveoli that cease to act in gas exchange due to collapse of obstruction |
| total dead space | sum of alveolar and anatomical dead space |
| spirometer | an instrument consisting of a hollow bell inverted over water, used to evaluate respiratory function
can distinguish between:-obstructive pulmonary disease-increased airway resistance
-restrictive disorders-reduction in total lung capacity from structur |
| total ventilation | total amount of gas flow into or out of the respiratory tract in one minute |
| forced vital capacity(FVC) | gas forcibly expelled after taking a deep breath |
| forced expiratory volume (FEV) | the amount of gas expelled during specific time intervals of the FVC |
| pulmonary function tests | increases in TLC, FRC and RV may occur as a result of obstructive disease- COPD->pus build up in lungs
reduction in VC, TLC, FRC, and RV result from restrictive disease- asthema |
| alveolar ventilation rate (AVR) | measures the flow of fresh gases into and out of the alveoli during a particular time
slow, deep breathing increases AVR and rapid shallow breathing decreases AVR |
| nonrespiratory air movements | most result from reflex action
examples inclue:coughing, sneezing, crying, laughing, hiccupping, and yawning |
| dalton's law of partial pressures | total pressure exerted by a mixture of gases is the sum of the pressures exerted independently by each gas in the mixture
the partial pressure of each gas is directly proportional to its percentage in the mixture
add up the partial pressures |
| Henrys law | when mixture of gases in contact with a liquid,each gass will dissolve in liquid in proportion to its partial pressure
dissolves gases into fluids
O2&CO2 under same pressure
CO2 will dissolve easier/better into water/blood then O2
need hemoglobin carr |
| ventilation-perfusion coupling | ventilation-amount of gas reaching the alveoli
perfusion-blood flow reaching the alveoli
ventilation&perfusion must be tightly regulated for efficient gas exchange
breathing has to match blood flow |
