The entire process of exchanging gases between the atmosphere and body cells.
Pulmonary ventilation, external ventilation, internal ventilation.
Events of respiration
The movement of air into and out of the lungs. Composed of inspiration (inhalation) and expiration (exhalation).
Gas exchange between blood and air in the lungs.
Gas exchange between blood and body cells.
Oxygen utilization and CO2 production at the cellular level.
Pressure inside alveoli must become _______ that atmospheric pressure for air flow _____ the lungs.
Pressure of a gas in a closed container is inversely proportional to the volume of the container.
Lungs must expand, increasing volume, decreasing pressure below atmospheric pressure.
Inhilation is: active or inactive?
Inhilation is contraction of:
Diaphragm, external intercostals, and accessory muscles
Most important muscle of inhilation.
Diaphragm is responsible for ____% of air entering lungs during normal quiet breathing.
External intercostals are responsible for ____% of air enter lungs during normal quiet breathing.
When thorax expands, parietal and visceral pleurae adhere tightly due to:
Subatmospheric pressure and surface tension
As lung volume ________, alveolar (intrapulmonic) pressure ______.
increases; drops OR drops; increases
During expiration, pressure in lungs is _________ than atmospheric pressure.
Expiration is normally _________(passive or active?).
Passive-muscles relax instead of contract
Expiration is based on elastic recoil of chest wall and lungs from elastic fibers and ______ ______ of alveolar fluid.
The diaphragm becomes _________ during expiration.
Exhalation only actice during _________ breathing.
Three factors that affect rate of airflow and ease of pulmonary ventilation.
Surface tension of alveolar fluid, lung compliance, and airway resistance
This causes alveoli to assume smallet possible diameter.
High lung compliance means lungs and chest wall expand _______.
Larger diameter airway has ________ (more or less?) resistance.
One inspiration followed by one expiration is called a:
The measurement of respiratory volumes.
The four distinct respiratory volumes are:
Tidal, inspiratory reserve, expiratory reserve, and residual
The amount of air that enters or leaves the lungs during one normal respiratory cycle is the:
Tidal volume (TV)
Only about ___% of tidal volume reaches respiratory zone.
___% of the tidal volume remains in the conducting zone.
Conducting airways with air that does not undergo respiratory gas exchange.
Alveolar ventilation rate
During forced inspiration, an additional volume of air, the _______ ________ ______ can be inhaled into the lungs.
Inspiratory reserve volume (IRV)
During maximal forced expiration, an _______ _______ _______ additional air can be exhaled, but there remains a _______ _______ in the lungs.
Expiratory reserve volume (ERV); residual volume (RV)
________ air remains in the lungs at all times, so newly inhaled air is constantly ________ with old air.
This is the tidal volume plus IRV and ERV combined (maximum air exhaled after taking deepest breath possible).
Vital capacity (VC)
Vital capacity plus RV is the:
Total lung capacity (TLC)
Pressure of a specific gas is:
This is the sum of all the partial pressures.
P(N2) + P(O2) + P(H2O) + P(CO2) + P(other gases) =
Armospheric pressure (760 mmHg)
Each gas diffuses across a permeable membrane from the area where its partial pressure is ______ to the area where is partial pressure is ____.
The _______ the difference, the _______ the rate of diffusion.
Diffusion across the respiratory membrane.
Oxygen diffuses from alveolar air into blood of _______ _______.
Diffusion occurs until P(O2) of _______ _______ blood matches P(O2) of _______ ____.
Pulmonary capillary; alveolar air
________ _______ diffuses from deoxygenated blood in pulmonary capillaries into alveolar air.
Respiration in tissues throughout the body.
Oxygen diffuses from _______ ______ blood into _______ _______ during internald respiration.
Systemic capillary; tissue cells
Blood drops to ____mmHg by the time blood exits the systemic capillaries.
Carbon dioxide diffuses from _____ _____ into _____ _____ during internal respiration.
Tissue cells; systemic capillaries
The rate of external respiration depends on:
Surface area for gas exchange, diffusion distance, partial pressure gradient, breathing rate and depth.