Chapter 22: Respiratory System
The most powerful respiratory stimulus for breathing in a healthy person is due to which of the following chemicals?
CO2
Select the correct statement about oxygen transport in blood: During conditions of acidosis, hemoglobin is able to carry oxygen more efficiently. During conditions of alkalosis, more oxygen is released to the tissues. Exercise causes more oxygen to be released to the tissues. During normal activity, a molecule of hemoglobin returning to the lungs carries one molecule of O2.
Exercise causes more oxygen to be released to the tissues.
Which statement about CO2 is incorrect?
More CO2 dissolves in the blood plasma than is carried in the RBCs.
Respiratory zone of the lungs begins with?
Respiratory bronchioles
Select the correct statement about the pharynx.
The auditory tube drains into the nasopharynx.
Which of the following cells are composed of simple squamous epithelium?
Type 1 alveolar cells
The respiratory membrane is a combination of ________.
alveolar and capillary walls and their fused basement membranes
Most alveoli are clustered around which of the following tubes?
alveolar ducts
Which of the following determines lung compliance?
alveolar surface tension and extensibility of the lung tissue
Which of the following provide the greatest surface area for gas exchange?
alveoli
How is the bulk of carbon dioxide carried in blood?
as bicarbonate ion
Possible causes of hypoxia include all of the following except ________.
blocking of the esophagus
Which of the following maintains the patency (openness) of the trachea?
c-shaped rings of hyaline cartilage
Which of the following is not a structure of the right lung?
cardiac notch
Most inspired particles such as dust fail to reach the lungs because of the ________.
ciliated mucous lining in the nose
The erythrocyte count increases when an individual goes from a low to a high altitude because the ________.
concentration of oxygen is lower at high altitudes (hypoxia)
Oxygen and carbon dioxide are exchanged between the alveoli and capillaries in the lungs via which process?
diffusion
Unlike inspiration, quiet or normal expiration is a passive act because muscular contractions are not involved. Normal expiration depends on two factors. Which of the choices below lists those two factors?
elastic recoil of lungs and surface tension of alveolar fluid
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?
emphysema
Tidal volume is air ________.
exchanged during normal breathing
Each of the following will result in inspiration or an increase in the respiratory rate. Which of the following is the exception?
inflation of lungs
The amount of air that can be inspired above the tidal volume is called ________.
inspiratory reserve
Surfactant helps to prevent the alveoli from collapsing by ________.
interfering with the cohesiveness of water molecules, thereby reducing the surface tension of alveolar fluid
Which respiratory-associated muscles would contract if you were to blow up a balloon?
internal intercostals and abdominal muscles would contract
Respiratory control centers are located in the ________.
medulla and pons
Which of the following does not influence hemoglobin saturation?
nitric oxide
Which of the choices below is not a factor that promotes oxygen binding to and dissociation from hemoglobin? temperature partial pressure of carbon dioxide partial pressure of oxygen number of red blood cells
number of RBCs
Intrapulmonary pressure is the ________.
pressure within the alveoli
Each of the following is a stimulus for breathing except ____________________.
rising BP
The walls of the alveoli are composed of two types of cells, type I and type II. The function of type II is to ________.
secrete surfactant
No exchange of gas occurs here
segmental/tertiary bronchi
The nose serves all the following functions except ________. a site for gas exchange a passageway for air movement warming and humidifying the air cleansing the air
site for gas exchange
A primary factor responsible for holding the lungs to the thorax wall is ________.
surface tension of the fluid within the pleural cavity
A premature baby usually has difficulty breathing due to the lack of ________.
surfactant
Which of the choices below determines the direction of respiratory gas movement?
the difference in the partial pressures of the gas between each location (i.e. capillary/alveoli - etc.)
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
The functional residual capacity is ________.
the total amount of air remaining in the lungs after a tidal expiration
What process is completed by a system other than the respiratory system?
transport of nutrients and blood
Atelectasis (lung collapse) renders the lung useless for ventilation.
true
Dalton's law states that the total pressure exerted by a mixture of gases is the sum of the pressures exerted independently by each gas in the mixture.
true
Labored or difficult breathing is termed dyspnea.
true
The functions of the nasal conchae are to enhance the air turbulence in the cavity and to increase the mucosal surface area exposed to the air.
true
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 structures (tissue).
true
The lung volume that represents the total volume of exchangeable air (air that can move into and out of the lungs during ventilation) is the ________.
vital capacity
