No exchange of gases occurs here.
Secrete a fluid containing surfactant.
Type Il cells
Where the respiratory zone of the lungs begins.
Composed of simple squamous epithelium.
type l cells
Terminates in alveoli.
Composed of cuboidal cells.
Type Il cells
The respiratory membrane is composed of fused basement membrane of the capillary walls and ________.
type l cells
TV + IRV + ERV + RV
total lung capacity
ERV + RV
Functional residual capacity
TV + IRV + ERV
TV + IRV
The main site of gas exchange is the ________.
The loudness of a person's voice depends on the ________.
Force with which air brushes across the vocal folds
The walls of the alveoli are composed of two types of cells, type I and type II. The function of type II is to ________.
Complete the following statement using the choices below. Air moves out of the lungs when the pressure inside the lungs is ________.
greater than the preassure in the atmosphere
Unlike inspiration, expiration is a passive act because no muscular contractions are involved. Expiration, however, depends on two factors. Which of the choices below lists those two factors?
the recoil of elastic fibersthat were stretched during inspiration and the inward pull of surface tension due to the film of alveolar fluid
Which of the following maintains the patency (openness) of the trachea?
C-shaped cartilage rings
Intrapulmonary pressure is the ________.
pressure with in the veoli of the lungs
The relationship between gas pressure and gas volume is described by ________.
The statement, "in a mixture of gases, the total pressure is the sum of the individual partial pressures of gases in the mixture" paraphrases ________.
Surfactant helps to prevent the alveoli from collapsing by ________.
interfering with the cohesiveness of water molecules, ther by reducing the surace tension of aveolar fluid
For gas exchange to be efficient, the respiratory membrane must be ________.
0.5 to 1 micrometer thick
With the Bohr effect, more oxygen is released because a(n) ________.
decrease in PH(acidosis) weakens the hemoglobin-oxygen bond
The most powerful respiratory stimulus for breathing in a healthy person is ________.
increase of carbone dioxide
The local matching of blood flow with ventilation is ________.
) In the plasma, the quantity of oxygen in solution is ________.
only about 1.5% of the oxygen carried in the blood
Which of the following statements is incorrect?
respiratory rate is lowest in newborn infants
Which of the choices below describes the forces that act to pull the lungs away from the thorax wall and thus collapse the lungs?
the natural tendency for the lungs to recoil and the surface tension of the alveolar fluid
Which of the following counteracts the movement of bicarbonate ions from the RBC?
Which of the following is not a form of lung cancer?
Which of the following is not an event necessary to supply the body with O2 and dispose of CO2?
blood pH adjustment
The major nonelastic source of resistance to air flow in the respiratory passageways is ________.
Which of the following determines lung compliance?
aveolar surface tension
Tidal volume is air ________.
exchanged during normal breathing
Which of the choices below determines the direction of respiratory gas movement?
partial pressure gradient
Possible causes of hypoxia include ________.
too little oxygen in the atmosphere
The lung volume that represents the total volume of exchangeable air is the ________.
Because the lungs are filled with fluid during fetal life, which of the following statements is true regarding respiratory exchange?
respiratory exchanges are made through the placenta
) Which of the following is not a stimulus for breathing?
rising blood preasure
Respiratory control centers are located in the ________.
medulla and pons
The amount of air that can be inspired above the tidal volume is called ________.
Which statement about CO2 is incorrect?
A) Its concentration in the blood is decreased by hyperventilation.
B) Its accumulation in the blood is associated with a decrease in pH.
C) More CO2 dissolves in the blood plasma than is carried in the RBCs.
D) CO2 concentrations are greater in venous blood than arterial blood
More CO2 dissolves in the blood plasma than is carried in the RBCs.
Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by ________.
Select the correct statement about the pharynx.
the auditory tube drains into the nasopharynx
The larynx contains ________.
the thyroid cartilage
Which respiratory-associated muscles would contract if you were to blow up a balloon?
internal intercostals and abdominal muscle would contract
How is the bulk of carbon dioxide carried in blood?
as the bicarbinate oin in the plasma, after first entering the red blood cells
Which of the choices below is not a role of the pleura?
aids in blood flow to and from the heart because the heart sits between the lungs
Which of the following incorrectly describes mechanisms of CO2 transport?
attached to the heme part of hemoglobin
Factors that influence the rate and depth of breathing include ________.
voluntary cortical control
Which of the following provide the greatest surface area for gas exchange?
The respiratory membrane is a combination of ________.
alveolar and capillary walls and their fused basement membranes
Gas emboli may occur because a ________.
diver holds his breath upon ascent
Inspiratory capacity is ________.
the total amount of air that can be inspired after a tidal expiration
Which center is located in the pons?
pontine respiratory group (PRG)
The nose serves all the following functions EXCEPT ________.
as the direct initiator of the cough reflex
A premature baby usually has difficulty breathing. However, the respiratory system is developed enough for survival by ________.
Which of the following statements is true regarding the respiratory rate of a newborn?
the respiratory of a new born ,at its highest rate ,aproximately 40-80 respirations per minute.
Select the correct statement about the neural mechanisms of respiratory control.
the pons is thought to be instrumental in the smooth transition from inspriation to expiration.
Which of the choices below is NOT A FACTOR that promotes oxygen binding to and dissociation from hemoglobin?
number of res blood cells
The factors responsible for holding the lungs to the thorax wall are ________.
surface tention from pleural fluid and negative pressure in the pleural cavity
The erythrocyte count increases after a while when an individual goes from a low to a high altitude because the ________.
concentration of oxygen and/or total atmospheric pressure is lower at high altitudes
Most inspired particles such as dust fail to reach the lungs because of the ________.
ciliated mucous lining in the nose
Which of the following is NOT possible?
pressure gradiant equals gas flow over resistance
Select the correct statement about the physical factors influencing pulmonary ventilation.
A) A decrease in compliance causes an increase in ventilation.
B) A lung that is less elastic will require less muscle action to perform adequate ventilation.
C) As alveolar surface tension increases, additional muscle action will be required.
D) Surfactant helps increase alveolar surface tension.
Diff: 3 Page Ref: 820-821
as aveolar surface tension increases, additional muscle action will be requierd
Select the correct statement about oxygen transport in blood
a 50% oxygen satuation level of blood returining to the lungs might indicate an activity level higher than normal
Which of the disorders below is characterized by destruction of the walls of the alveoli producing abnormally large air spaces that remain filled with air during exhalation?
Which of the following does NOT influence hemoglobin saturation?
Type II alveolar cells secrete ________.
The law of partial pressure is called ________ law.
The law that applies to the amount of CO2 you could dissolve in a Pepsi is called ________ law.
The Bohr effect refers to the unloading of ________ in a RBC due to declining pH.
A disorder characterized by permanent enlargement of the alveoli accompanied by destruction of the alveolar walls is ________.
The cartilaginous flap that closes the trachea during swallowing is called the ________.
The archway in the back of the throat is called the ________.
isthmus of the fauces (oropharynx)
Terminal bronchioles are lined with ________ epithelium.