respiratory system 3

smallest of the conducting passageways

because of the branching and rebranching of the respiratory passageways within the lungs, the network formed is often referred to as the

air sacs

only site of gas exchangethercohe somecoaigasoxygenausewwhthrenormlua

serve as conduits to and from the respiratory zone

there are _ of the clustered alveoli, which resemble bunches of grapes, and they make up the bulk of the lungs

connect neighboring air sacs and provide alternative routes for air to reach alveoli whose feeder bronchioles have been clogged by mucus or otherwise blocked

the total gas exchange surface provided by the alveolar walls of a healthy man is estimated to be _

sometimes called the dust cells, wander in and out of the alveoli picking up bacteria, carbon particles, and other debris

coats the gas exposed alveolar surfaces and is very important in lung function

four distinct eventsespiration

air must move into and out of the lungs are continuously refreshed.

gas exchange between the pulmonary blood and alveoli must take place. remember that in ____, gas exchanges are being made between the blood and the body exterior

oxygen and carbon dioxide must be transported to and from the lungs and tissue cells of the body via the bloodstream

at systemic capillaries, gas exchange occurs between the blood and cells inside the body. this time, oxygen is unloaded from blood and co2 is loaded

the use of oxygen to produce ATP and carbon dioxide, is the cornerstone of all energy-producing chemical reactions and occurs in nearly all celss

when air is flowing into the lungs

when air is leaving the lungs

the volume within the lungs

atmospheric pressure is high and alveolar pressure is low

atmospheric pressure is low and alveolar pressure is high

respiratory passageways are narrowed by spasm of the bronchioles

respiratory passageways are clogged with mucus or fluid

internal intercostal muscles are activated to help depress the rib cage, and the abdominal muscles contract and help t force air from the lungs by squeezing the abdominal organs upward against the diaphragm

normal pressure within the pleural space

lung collapse, the lung is useless for ventilation. this phenomenon occurs when the air enters the pleural space through the chest wound, but it may also result from a rupture of the visceral pleura, which allows air to enter the pleural space from the respiratory tract

air in the intrapleural space, pushes in on the lung, disrupting the fluid bond between the pleurae