Represents friction and is a major non-elastic source of resistance to gas flow.

Where does airway resistance occur?

F= delta P/R

Gas flow changes inversely with resistance.

Resistance is usually very significant.

Where is resistance greatest?

Where does resistance dissapear?

As airway resistance rises, breathing becomes ___ strenuous.

dilates bronchioles and reduces air resistance

labored breathing

attracts liquid molecules to one another at gas-liquid interface

high surface tensions; coats alveolar walls and reduces alveoli to smallest size

detergent-like lipid and protein complex produced by type II cells

surfactant reduces surface tension of alveolar fluid and discourages alveolar collapse

measure of change in lung volume that occurs with given change in transpulmonary pressure

lung compliance is normally ____.

What causes high lung compliance?

The opposite of lung stretch (distensibility)

total compliance of the respiratory system is influenced by

paralysis of intercostal muscles will cause a ___ in total compliance

amount of air inhaled or exhaled with each breath under resting conditions

amount of air that can be forcefully inhaled after a normal tidal volume inspiration

amount of air that can be forcefully exhaled after a normal tidal volume expiration

amount of air remaining in lungs after a forced expiration.

No gas exchange (conducting zone)

Which one is the "dead zone"?

non-functional alveoli due to collapse or obstruction

conducting zone

sum of anatomical and alveolar dead space

total amount of gas flow into or out of respiratory tract in 1 minute

flow of gases into and out of alveoli during a particular time

Select all of the following that are nonrespiratory air movements

diffusion of gases at body tissues

diffusion of gases in lungs

internal and external respiration both involve physical properties of gases and composition of alveolar gase

pressure exerted by each gas in a mixture of gases

Each gas dissolves in a liquid in proportion to its partial pressure

Which is more soluble?

the amount of gas that dissolves in a liquid depends on

For GASES, if temperature increases, solubility of the gas ____

Alveoli contain more water vapor and CO2 than atmospheric air

External respiration happens at

internal respiration influence by

Respiratory membranes will thicken if

emphysema, tumors, inflammation, mucus will cause ___ surface area.

Which has less pressure?

which has more pressure?

Fast blood flow will cause inadequate gas exchange at the alveoli.

equilibrium across the respiratory membrane of the alveoli is reached in

Which has a steep partial pressure gradient?

Venous blood = 40 mmHg Alveolar = 104 mmHg for

Venous blood = 45 mmHg Alveoli = 40 mmHg for

Which does NOT have a steep partial pressure gradient?

Because the pressure gradient is not as steep, CO2 diffuses in less amounts than oxygen.

CO2 has ___ pressure in blood than alveoli.

blood flow reaching alveoli

amount of gas reaching alveoli

Ventilation and perfusion is ___ balanced for alveoli.

If arterioles constrict, perfusion ____ and ventilation ____.

If arterioles dilate, perfusion ___ and ventilation ___.

Where alveolar O2 is high, arterioles ____

Where alveolar O2 is low, arterioles ____.

Where CO2 is high, bronchioles ____

Where CO2 is low, bronchioles ____

Changes in ___ in alveoli cause changes in diameters of arterioles.

Changes in ____ in alveoli cause changes in diameters of bronchioles.

Tissue PO2 is always ____ than in systemic arterial blood.

Molecular O2 carried in blood is

98.5% of oxygen in the blood is

Reduced hemoglobin

3 or less O2 bound to hemoglobin

Most primary reason to breath is the presence of

A right shift in hemoglobin oxidation curve means