Breathing Mechanism
During normal quiet breathing, the lungs are expanded almost entirely by the downward movement of this muscle
This is the pressure of the fluid in the thin space between the lung pleura and the chest wall, which is normally a slight suction
Pleural Pressure
This is the volume of air inspired or expired with each normal breath, averaging about 500 ml in a healthy man
Tidal Volume
These microscopic structures line the respiratory passages and beat 10 to 20 times per second to move mucus toward the pharynx
Ciliary Power
This mechanical function of speech is achieved specifically by the larynx
Phonation
These specific muscles contract to pull the upper ribs forward and upward, functioning as muscles of inspiration
External intercostal
This term describes the extent to which the lungs will expand for each unit increase in transpulmonary pressure
Lung Compliance
This capacity, totaling about 4600 ml, is the maximum amount of air a person can expel after first filling the lungs to their maximum extent
Vital capacity
Triggered by irritation in the trachea or bronchi, this process can expel air at velocities ranging from 75 to 100 miles per hour
Cough Reflex
This is the common name for the thyroid cartilage, to which the vocal ligaments are attached anteriorl
During heavy breathing, extra force to expel air is achieved mainly by the contraction of these muscles
Abdominal muscles
These granular epithelial cells constitute about 10% of the alveolar surface and are responsible for secreting surfactant
Type II cells
This is the volume of air that remains in the lungs even after the most forceful expiration
Residual volume
The nose performs three functions for inspired air: it is warmed, humidified, and partially filtered
Nasal air conditioning
This function of speech involves the structures of the mouth, specifically the lips, tongue, and soft palate
Articulation
During high-intensity breathing, these three specific muscle groups—the sternocleidomastoid, anterior serrati, and scaleni—assist by lifting the sternum and the first two ribs to further expand the chest
Accessory Inspiratory Muscles
it is a measure of the elastic forces in the lungs that tend to collapse the lungs at each instant of respiration
Recoil pressure
This term refers to air that fills respiratory passages, such as the trachea, but never reaches the gas exchange areas
Dead space air
This mechanism in the nasal passages uses conchae to force air to change direction, causing heavier particles to hit and stick to the mucous coating
Turbulent Precipitation
When the adrenal glands release epinephrine into the blood, it causes this effect on the bronchial tree.
Sympathetic Dilation
This muscle of inspiration lifts the first two ribs
Scaleni
This combined value of 110 ml/cm H2O is roughly half that of isolated lungs, explaining why twice the pressure is required to inflate the respiratory system while it is inside the chest cage.
Lung-thorax compliance
Because residual volume cannot be expired into a spirometer, this indirect method is used to measure functional residual capacity
Helium dilution
Particles that reach the alveoli and are not expelled may be removed by these specialized cells
Alveolar Macrophages
Activated vagus nerves secrete acetylcholine, which causes mild to moderate narrowing of these respiratory passages
Parasympathetic Constriction