Chapter 7 Flashcards
alveoli
saclike structures that facilitate gas exchange in the respiratory zone.
Boyles Gas Law
gas law states that at a given constant temperature, pressure and volume are inversely proportional to each other.
Expiration
(usually) passive process of breathing out air.
External Respiration
physiological process of gas exchange between lungs and pulmonary capillary blood.
Internal Respiration
physiological process of gas exchange between the blood and body tissues.
Pulmonary ventilation
breathing, is the process by which a person moves air into and out of the lungs.
respiratory pump
assists with venous return when a person changes intra-abdominal and intrathoracic pressures by breathing in and out
Residual volume
volume of air left in the lungs after a person has exhaled as much as possible.
Total lung capacity
= vital capacity + residual volume
vital capacity
The maximal amount of air that a person can exhale after a maximal inhalation
spirometry
Lung volumes, capacities, and flow rates are measured using a technique
tidal volume
volume of air entering and leaving the lungs during quiet breathing
respiratory membrane
structure in the lungs that is composed of the alveolar wall, the capillary wall, and their respective basement membranes
Dalton’s law
total pressure of a mixture of gases (like atmospheric air) equals the sum of the partial pressures of the individual gases in the mixture.
Fick’s law
states that the rate of gas diffusion through a tissue (like the respiratory membrane) is proportional to the surface area and the gas partial pressure gradient.
Henry’s Law
states that gases dissolve in liquids in proportion to their respective partial pressures
oxygen diffusion capacity
- rate at which oxygen can diffuse from the alveoli into the blood.
- expressed as the volume of oxygen that diffuses through a membrane per minute per 1 mmHg of pressure difference.
pulmonary diffusion
When gases move across the respiratory membrane and are exchanged between the alveoli and the pulmonary capillary blood
hemoglobin
majority of oxygen transported in the blood is bound to
Bohr Effect
When the oxyhemoglobin dissociation curve shifts to the right from changes in pH or temperature
carbaminohemoglobin
When carbon dioxide is bound to hemoglobin
Oxyhemoglobin dissociation curve
graphical representation of the relationship between the partial pressure of oxygen and the degree of hemoglobin saturation.
bicarbonate ion
majority of carbon dioxide in the blood is transported as
arterial-mixed venous oxygen difference
-difference in oxygen content between arterial and mixed venous blood.
- index of oxygen extraction by body tissues.
myoglobin
- Within muscle cells, what oxygen is transported by.
-higher affinity for oxygen than hemoglobin has
Compared to the oxyhemoglobin dissociation curve, the oxygen-myoglobin dissociation curve is shifted to the?
left
respiratory centers
found in the medulla oblongata and pons regions of the brain stem, help establish the rate and depth of breathing.
Central chemoreceptors
trigger an increase in breathing rate and depth when stimulated by high CO2 concentrations in cerebrospinal fluid.
Mechanoreceptors
in the pleurae, bronchiole, and alveoli respond to excess stretch by signaling for a decrease in inspiratory rate.
The majority of carbon dioxide in the blood is transported as
bicarbonate ions
According to ________ law, the total pressure of a mixture of gases (like atmospheric air) equals the sum of the partial pressures of the individual gases in the mixture
Daltons
Hering-Breuer reflex
When pulmonary stretch receptors send a signal that triggers a shortened duration of inspiration, it is known as the
When you inhale, which of the following occurs as a result of the respiratory pump?
Thoracic vena cavae fill
visceral pleura
anchoring membrane that attaches to the lungs themselves
Physiological “dead space” is composed of all of the following EXCEPT
bronchioles
During heavy exercise, inhalation is assisted by all of the following EXCEPT
internal intercostals
residual volume
volume of air that remains in the lungs after expiration and cannot be exhaled
The pressure gradient that is found in the pulmonary circulation (i.e., from pulmonary arteries to pulmonary veins or left atrium) is approximately
10 mmHg
PCO2 in the alveoli is approximately
40 mmHg
During exercise, the oxygen diffusion capacity increases dramatically because
lower venous O2 content increases the PO2 gradient
The maximum total O2-carrying capacity for a person with a blood volume of 5 L would be approximately
1 L O2
If PO2 is high, a large change in PO2 would lead to _____________ in hemoglobin saturation.
small change
In hemoglobin, CO2 binds to
globular protein
As bicarbonate diffuses from the red blood cell into the plasma, __________ moves from the plasma into the red blood cell to prevent electrical imbalance.
chloride
Compared to the slope of the oxyhemoglobin dissociation curve, the slope of the O2-myoglobin dissociation curve i
steeper but in the same direction
When venous blood from exercising and nonexercising tissues is included in the calculation, it is
arterial-mixed venous O2 difference
