The respiratory membrane is composed of fused membrane of the capillary walls and...
Type I cells
No exchange of gases occurs here
Ventilation perfusion coupling means that more blood flows past functional alveoli than past nonfunctional alveoli?
The olfactory mucosal lining of the nasal cavity contains the receptors for the sense of smell?
The functions of the nasal conchae are to enhance the air turbulance in the cavity and to increase the mucosal surface area exposed to the air?
The lungs are perfused by two circulations: the pulmonary and the bronchial. The pulmonary circulation is for oxygenation of blood. The bronchial circulation supplies blood to the lung tissue?
Changes in arterial pH can modify respiration rate and rythm even when carbon dioxide and oxygen levels are normal?
Intralpleural pressure is normally about 4mm Hg less than the pressure in the alveoli?
During normal quiet breathing, aproximately 750ml of air moves into and out of the lungs with each breath?
The alveolar ventilation rate is the best index of effective ventilation?
In chronic bronchitis, mucus production is decreased and this leads to the inflammation and fibrosis of the mucosal lining of the bronchial tree?
Labored breathing is termed dispenea?
The largest amount of carbon dioxide is transported in the bloodstream in the form of carbonic anhydrase?
Increased temperature results in decreased O2 unloading from hemoglobin?
The epiglottis is a smooth muscle that covers the glottis during swallowing?
Valsalva's maneuver involves closing off the glottis (preventing expiration) while contracting the muscles of expiration, causing an increase in intra-abdominal pressure?
Smoking diminishes ciliary action and eventually destroys the cilia?
Tracheal obstruction is life threatening?
The parietal pleura lines the thoracic wall?
The average individual has 500ml of residual volume in his lungs?
Atelectasis (lung collapse) renders the lung useless for ventilation?
The hering-breuer reflex is a potentially dangerous response that may cause overinflation of the lung?
Strong emotions and pain acting through the limbic system activate sympathetic centers in the hypothalmus, thus modulating respiratory rate and depth by sending signals to the respiratory centers?
As carbon dioxide enters systemic blood, it causes more oxygen to dissociate from hemoglobin (the haldane effect), which in turn allows more CO2 to combine with hemoglobin and more biocarbonate ion to be generated (the Bohr effect)?
Dalton's law states that the total pressure exerted by a mixture of gases in the sum of the pressures exerted independently by each gas in the mixture?
Oxygenated hemoglobin releases oxygen more readily when the pH is more basic?
Nasal cochae mainly work on inhalation to warm and moisten air. They serve minor functions for exhalation?
Under certain conditions, the vocal folds act as a sphincter that prevents air passage?
Apneustic breathing is characterized by prolonged inspirations?
Which of the choices below is NOT a functional process performed by the respiratory system?
C) Transport of respiratory gases
The loudness of a person's voice depends on the...
A) Force with which air rushes across the vocal folds
The walls of the aveoli are composed of two types of cells, type I and type II. The function of type II is to...
B) Secrete surfactant
Complete the following statement using the choices below. Air moves out of the lungs when the pressure inside the lungs is...
D) Greater than the pressure 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?
C) The recoil of elastic fibers that 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) cartilage rings
Intrapulmonary pressure is the...
C) pressure within the alveoli of the lungs
The relationship between the pressure and volume of gases is given by
A) Boyle's law
The statement "in a mixture of gases, the total pressureis the sum of the individual partial pressures of gases in the mixture" paraphrases...
B) Dalton's law
Surfactant helps to prevent the alveoli from collapsing by...
B) interfering with the cohesiveness of water molecules, thereby reducing the surface tension of the alveolar fluidinterfering with the cohesiveness of water molecules, thereby reducing the surface tension of the alveolar fluid
For gas exchanges to be efficent, the respiratory membrane must be...
D) 0.5 to 1 micrometer thick
with the Bohr effect, more oxygen is released because a(n)...
A) decrease in pH (acidosis) weakens the hemoglobin-oxygen bond
The most powerful respiratory stimulus for breathing in a healthy person is ...
B) increase of carbon dioxide
Nerve impulses from will result in inspiration.
B) the ventral respiratory group
In the plasma, the quantity of of oxygen in solution is...
A) only about 1.5% of the oxygen carried in dissolved form
which of the following statements is in correct?
A) 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 ant thus collapse the lungs?
C) the natural tendency for the lungs to rrecoil and the surface tension of the alveolar fluid
which of the following does not influence the increase in ventilation that occurs as exercise is initiated?
C) decrese in lactic acid levels
which of the following is not a from of lung cancer?
C) Kaposi's sarcoma
Which of the following is not an event necessary to supply the body with O2 and dispose of CO2?
B) blood pH adjustment
Which of the following is not true of the respiratory tract from the medium bronchi to the aalveoli?
D) resistance to air flow increases due to the increase in cross-sectional diameter
which of the following determines lung compliance?
B) alveolar surface tension
Tidal volume is air.
C) exchanged during normal breathing
Which of the choices below determines the direction of respiratory gas movement?
A) partial pressure gradient
possible causes of hypoxia include.
B) too little oxygen in the air
The lung volume that represents the total volume of exchangable air is the.
D) vital capacity
Because the lungs are filled with fluid during fetal life, which of the folowing statements is true regarding respiratory exchange?
C) respiratory exchanges are made through the placenta
Which of the following is not a stimulus for breathing?
D) rising blood pressure
Respiratory control centers are located in the.
D) medulla and pons
The amount of reserve that can be inspired above the tidal volume is called.
C) inspiratory reserve
Which statement about CO2 is incorrect?
A) More CO2 dissolves in the blood plasma than is carried in the RBC's
Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by.