Deep inhalation...active process
diaphragm and ext. int
scalenes rib pairs 1-2, sternocleomastoid: elevates sternum , pec minor: elevates ribs 3-5Forced expirationrectus abdominus
external and internal oblique
transversus abdominus
internal intercostalspressure within the pleural cavity
keeps lungs inflated between breathsintrapleural pressure
remains negative
more negative when inhalepressure within the alveoli of the lungsintrapulmonary pressure
negative compared to atmosphere when inhaleConducting pathway structures (7)nose pharynx larynx trachea primary bronchi bronchioles terminal bronchiolesFxn of the conducting pathwaymove air
filter warm and humidify air
no gas exchangeRespiratory pathway structures (3)respiratory bronchioles
alveolar ducts
alveolar sacsWhere are central chemoreceptors located and what do they do?medulla oblongata
respond to pH of CSF which reflects CO2 amount in bloodWhere are peripheral chemoreceptors located and what do they do?Carotid and aortic bodies
respond to O2 and CO2 in bloodWhere are stretch receptors located and what do they do?smooth bronchi
bronchioles
visceral pleura
respond to inflation of lungsWhere are irritant receptors located and what do they do?epithelial cells of airway
respond to dust, smoke, dirt, pollen, cold air, excess mucusWhere is surfactant produced and what is it's purpose?type 2 alveoli cells
mixes with alveolar fluid to decrease surface tension and keep sacs inflatedhow much effort is required to stretch the lungs and chest wallCompliancecompliance is dependent on...elasticity and surface tensionList the factors that affect breathingcentral chemoreceptors
peripheral chemoreceptors
irritant receptors
surface tension
surfactant
compliance
airway resistancepressure exerted by a gas when mixed with other gasespartial pressureEach gas in a mixture of gases exerts its own pressure as if no other gases were presentdalton's lawquantity of gas that will dissolve in a liquid is proportional to partial pressure of gas and its solubilityhenry's lawwhy are the alveoli so efficient at gas exchange?large surface area and small diffusion distanceexplain how O2 and CO2 are transported in systemic gas exchangeo2 exits via arteriole side CO2 enters cap via venule sidewhen cells are at rest how much O2 do they need?25%blood transport of O21.5% dissolved in plasma 98.5% on hgbpartial pressure of Oxygen and hemoglobin saturationpartial pressure O2 greater in pulmonary capillaries so O2 bings to hgb
Partial pressure O2 less in tissue capillaries so it diffuses into tissue instead of hgb bindingFactors affecting gas exchange1) pressure gradient of the gases
2) solubility of the gases
> CO2 is 20X as soluble as O2
> O2 is 2X as soluble as N2
3) membrane thickness
4) membrane surface area
