Nitrous Oxide 1 Flashcards
(53 cards)
What are the 3 separate functions of respiration?
- ventilation
- gas exchange
- O2 utlilization
T/F. Ventilation is the same as breathing. O2 utilization is cellular respiration.
Both statements are true.
Gas exchange is between air and capillaries in the ___ and between systemic capillaries and tissues of the ___.
lungs; body
___ is the mechanical process that moves air in and out of the lungs. [O2] of air is ___ (lower/higher) in the lungs than in the blood. O2 diffuses from ___ to ___.
Ventilation; higher; air; blood
___ moves from the blood to the air by diffusing down its concentration gradient.
CO2
T/F. Gas exchanges occurs entirely by diffusion.
True
Which alveolar cells are structural and which secrete surfactant?
type 1 - structural
type 2 - secrete surfactant
Which zone is a region of gas exchange between air and blood that includes respiratory bronchioles, alveolar sacs and must contain alveoli?
respiratory zone
Describe the conducting zone.
All the structures air passes through before reaching the respiratory zone.
- Warms and humidifies inspired air.
- Filters and cleans:
Mucus secreted to trap particles in the inspired air.
Mucus moved by cilia to be expectorated.
T/F. Elasticity is distensibility (stretchability). or the ease with which the lungs can expand. It is reduced by factors that produce resistance to distension.
False, both statements refer to compliance
Elasticity is the tendency to return to initial size after distension.
___ ___ is the force exerted by fluid in alveoli to resist distension.
surface tension
H2O molecules at the surface are attracted to other H2O molecules by ___ forces.
attractive
the force is directed inward, raising the pressure in alveoli.
Law of Laplace states the pressure in alveoli is directly proportional to ___ ___ and inversely proportional to ___ of alveoli. Therefore, pressure in ____ (smaller/larger) alveoli is greater.
surface tension; radius; smaller
P= (2 x T) / r
How does surfactant lower surface tension?
reduces attractive forces of hydrogen bonding by becoming interspersed between H2O molecules
T/F. As alveoli radius decreases, surfactant’s ability to lower surface tension increases.
True
___ law states that changes in intrapulmonary pressure occur as a result of changes in lung volume.
Boyle’s
pressure of gas is inversely proportional to its volume.
Which way does air flow?
- Increase in lung volume decreases intrapulmonary pressure.
- decrease in lung volume, raises intrapulmonary pressure above atmosphere.
- air goes in
2. air goes out
What is the intra-alveolar pressure (pressure in the alveoli)?
intrapulmonary pressure
T/F. Intrapleural pressure is postive due to lack of air in the intrapleural space.
False, pressure is NEGATIVE.
What is the pressure difference across the wall of the lung?
transpulmonary pressure
What pressure is the intrapulmonary pressure - intrapleural pressure?
transpulmonary pressure.
it keeps the lungs against the chest wall.
Describe the active process of quiet inspiration.
Contraction of diaphragm, increases thoracic volume vertically.
Contraction of parasternal and internal intercostals, increases thoracic volume laterally.
Increase in lung volume decreases pressure in alveoli, and air rushes in.
Match the pressure changes during INSPIRATION.
- alveolar
- intrapleural
- transpulmonary
A. = +3 mm Hg
B. -4 to -6 mm Hg
C. 0 to -3 mm Hg
- C
- B
- A
Match the pressure changes during EXPIRATION.
- alveolar
- intrapleural
- transpulmonary
A. = -3 to +3 mm Hg
B. +6 mm Hg
C. -6 to -3 mm Hg
- A
- C
- B
