Conducting Zone Involuntary Control (continued)
Functions Input received from:
Respiratory Zone Chemoreceptors in:
Boyle’s Law Aorta
Muscles of Quiet Respiration Carotids
Diaphragm Chemosensitive Area
External Intercostals (in Medulla Oblongata)
Muscles of Forced Respiration Baroreceptors in:
Forced Inspiration/Inhalation Aorta
Sternocleidomastoid Carotids
Pectoralis Minor Stretch Receptors (in lung)
Forced Expiration/Exhalation Hering-Breuer Reflexes
Inflation Reflex
External Abdominal Oblique
Deflation Reflex
Internal Abdominal Oblique
Voluntary Control
Transverses Abdominus Originates from higher brain
Rectus Abdominus areas (Cerebrum)
Lung Function Affected By Can bypass respiratory centers
Compliance (need to maximize) of brain and take direct
Elasticity (need to maximize) control over breathing
Surface Tension (need to minimize) muscles (which are skeletal
Surfactant (contraction of Surface Active Agent) muscle)
Produced inside alveoli E.g., speaking and singing
Cuts surface tension by breaking Can stimulate or inhibit the
hydrogen bonds Pneumotaxic and
Produced by Type II (Septal Cells) Apneustic Centers
Important in holding breath
Respiratory Distress Syndrome in
premature babies
Type I cells in alveoli form the respiratory Terms relevant to respiratory rate
membrane across which gas Hyperventilation vs. Tachypnea
exchange occurs Hypoventilation
Control of Respiration Apnea
Local Control
Alveolar Capillaries Respiratory Minute Volume
Bronchioles ⚫
VE = f x VT
Control by Brain
f = Respiratory Rate
Involuntary Control VT = Tidal Volume
Structure in Medulla Oblongata: Alveolar Ventilation
Rhythmicity Center/Area ⚫
Structures in Pons: VA = f x (VT – VD)
Apneustic Center/Area VD = Volume of Anatomic
Pneumotaxic Center/Area Dead Space
(continued)