Chapter 22 - Respiratory System
Which of the following does not influence hemoglobin saturation?
D
Major organs of the respiratory system
-Nose, nasal cavity, paranasal sinuses. -Pharynx -Larynx -Trachea -Bronchi and their branches -Lungs and aveoli
For gas exchange to be efficient, the respiratory membrane must be ________.
0.5 to 1 micrometer thick
Regions of the nose
1. External nose: Root, bridge, dorsum nasi, and apex - also philtrum and nares (nostrils) 2. Nasal cavity: In and posterior to the external nose, divided by a midline nasal eptum.
Walls of trachea
1. Mucosa: Ciliated pseudostratified epithelium with goblet cells. 2. Submucosa: Connective tissue with seromucous glands. 3. Adventritila: Outermost layer made of connective tissue that encases the C-shaped rings of hyaline cartilage.
Functions of the nose (5)
1. Provides an airway for respiration. 2. Moistens and warms the entering air. 3. Filters and cleans inspired air (nose hairs!) 4. Serves as a resonating chamber for speech. 5. Houses olfactory receptors.
Select the correct statement about the neural mechanisms of respiratory control. A) The pons is thought to be instrumental in the smooth transition from inspiration to expiration. B) The dorsal respiratory group neurons depolarize in a rhythmic way to establish the pattern of breathing. C) The pontine respirator group (PRG) continuously stimulates the medulla to provide inspiratory drive. D) The ventral respiratory group is contained within the pons.
A
Which of the choices below describes the forces that act to pull the lungs away from the thorax wall and thus collapse the lungs? A) the natural tendency for the lungs to recoil and the surface tension of the alveolar fluid B) compliance and transpulmonary pressures C) the natural tendency for the lungs to recoil and transpulmonary pressures D) compliance and the surface tension of the alveolar fluid
A
Oxygen and carbon dioxide are exchanged in the lungs and through all cell membranes by...
Diffusion
The larynx contains...
A thyroid cartilage.
Alveoli
Account for most of the lungs volume; main site of gas exchange.
38) Which of the choices below is not a role of the pleura? A) allows the lungs to inflate and deflate without friction B) helps divide the thoracic cavity into three chambers C) helps limit the spread of local infections D) aids in blood flow to and from the heart because the heart sits between the lungs
Aids in blood flow to and from the heart.
Nasopharynx
Air passageway posterior to the nasal cavity. Soft palate and uvula close nasopharynx during swallowing.
Physical factors influencing pulmonary ventilation
Airway resistance Alveolar surface tension Lung compliance
42) The respiratory membrane is a combination of ________. A) respiratory bronchioles and alveolar ducts B) alveolar and capillary walls and their fused basement membranes C) atria and alveolar sacs D) respiratory bronchioles and alveolar sacs
Alveolar and capilary walls and their fused basement membranes.
Which of the following determines lung compliance?
Alveolar surface tension
41) Which of the following provide the greatest surface area for gas exchange? A) alveolar sacs B) alveoli C) respiratory bronchioles D) alveolar ducts
Alveoli
Tidal volume
Amount of air inhaled or exhaled with each breath under resting conditions.
Residual volme
Amount of air remaining in the lungs after forced exhalation.
Expiratory reserve volume
Amount of air that can be forcefully exhaled after a normal tidal volume exhalation.
Inspiratory reserve volume
Amount of air that can be forcefully inhaled after a normal tidal volume inhalation.
How is the bulk of carbon dioxide carried in blood?
As the bicarbonate ion in the plasma after first entering the red blood cells.
39) Which of the following correctly describes mechanisms of CO2 transport? A) 710% of CO2 is dissolved directly into the plasma B) 20% of CO2 is carried in the form of carbaminohemoglobin C) as bicarbonate ion in plasma D) attached to the heme part of hemoglobin
Attached to the heme part of hemoglobin.
Larynx
Attaches to the hyoid bone. Helps to close glottis during swallowing. Functions 1. Provides a patent airway 2. Routes air and food int proper channels. 3. Voice production.
Alveolar surface tension
Attracts liquid molecules to one another at a gas-liquid interface - resists any force that tends to increase the surface area of the liquid.
19) Which of the following is not a form of lung cancer? A) adenocarcinoma B) Kaposi's sarcoma C) small cell carcinoma D) squamous cell carcinoma
B
21) Which of the following is not true of the respiratory tract from the medium bronchi to the aveoli? A) Cartilage gradually decreases and disappears at the bronchioles. B) Resistance to air flow increases due to the increase in cross-sectional diameter. C) Proportionally, smooth muscle decreases uniformly. D) Lining of the tubes changes from ciliated columnar to simple squamous epithelium in the alveoli.
B
The nose serves all the following functions except ________. A) as a passageway for air movement B) as the initiator of the cough reflex C) warming and humidifying the air D) cleansing the air
B
Which of the choices below determines the direction of respiratory gas movement? A) solubility in water B) partial pressure gradient C) the temperature D) molecular weight and size of the gas molecule
B
Which of the following does not influence the increase in ventilation that occurs as exercise is initiated? A) psychic stimuli B) decrease in lactic acid levels C) proprioceptors D) simultaneous cortical motor activation of the skeletal muscles and respiratory center
B
Which of the following is not an event necessary to supply the body with O2 and dispose of CO2? A) pulmonary ventilation B) blood pH adjustment C) internal respiration D) external respiration
B
Which of the following is not possible? A) Gas flow equals pressure gradient over resistance. B) Pressure gradient equals gas flow over resistance. C) Resistance equals pressure gradient over gas flow. D) The amount of gas flowing in and out of the alveoli is directly proportional to the difference in pressure or pressure gradient between the external atmosphere and the alveoli.
B
Paranasal sinuses
In frontal, sphenoid, ethmoid, and maxillary bones. Lighten the skull and help to warm and moisten the air.
The relationship between the pressure and volume of gasses is given by...
Boyle's Law
A premature baby usually has difficulty breathing. However, the respiratory system is developed enough for survival by ________. A) 17 weeks B) 24 weeks C) 28 weeks D) 36 weeks
C
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.
C
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?
C
The factors responsible for holding the lungs to the thorax wall are ________. A) the smooth muscles of the lung B) the diaphragm and the intercostal muscles alone C) the visceral pleurae and the changing volume of the lungs D) surface tension from pleural fluid and negative pressure in the pleural cavity
D
37) Which of the following is not found on the right lobe of the lung? A) middle lobe B) cardiac notch C) horizontal fissure D) oblique fissure
Cardiac notch
What maintains the patency (openness of the trachea?
Cartilage rings
Conducting zone
Conduits to gas exchange sites.
48) Which of the following statements is true regarding the respiratory rate of a newborn? A) The respiratory rate of a newborn is slow. B) The respiratory rate of a newborn varies between male and female infants. C) The respiratory rate of a newborn is approximately 30 respirations per minute. D) The respiratory rate of a newborn is, at its highest rate, approximately 40-80 respirations per minute.
D
Select the correct statement about oxygen transport in blood:
D
The erythrocyte count increases after a while when an individual goes from a low to a high altitude because the ________. A) temperature is lower at higher altitudes B) basal metabolic rate is higher at high altitudes C) concentration of oxygen and/or total atmospheric pressure is higher at higher altitudes D) concentration of oxygen and/or total atmospheric pressure is lower at high altitudes
D
Which of the choices below is not a factor that promotes oxygen binding to and dissociation from hemoglobin? A) partial pressure of oxygen B) temperature C) partial pressure of carbon dioxide D) number of red blood cells
D
"in a mixture of gases, the total pressure is the sum of the individual partial pressures of gases in the mixture" paraphrases ________.
Dalton's law
Respiratory pressure
Described relative to atmospheric pressure. Negative is less than atmospheric pressure. Positive results in exhalation.
Furfactant
Detergent like lipid produced by type II alveolar cells- reduces surface tension and discourages alveolar collase. Insufficient quantity in premature infants causes infant respiratory distress symptom (it's produced at 28 weeks).
Respiratory muscles
Diaphragm and other muscles that promote ventilation. Inhalation is an active process that depends on muscles (exhalation is passive).
Gas emboli may occur because a...
Diver holds his breath upon ascent.
Roof of nasal cavity (Bones)
Ethmoid and sphenoid
Total volume is air....
Exchanged during normal breathing.
The loudness of a person's voice depends on...
Force with which air rushes across vocal folds.
Airway resistance
Friction is major nonelastic source of resistance to gas flow. Resistance is usually insignificant because of large airway diameters. As resistance rises, breathing becomes more strenuous.
Respiration
Gas exchange.
Expiration
Gases exit the lungs. Normally a passive process - but doesn't have to be, forced expiration is active using abdominal and internal intercostal muscles.
Inspiration
Gases flow into the lungs. An active process.
Air moves out of the lungs when the pressure inside the lungs is...
Greater than the pressure in the atmosphere.
Floor of nasal cavity (bones)
Hard and soft palates.
The most powerful respiratory stimulus for breathing in a healthy person is ________.
Increase in carbon dioxide.
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.
35) Which respiratory-associated muscles would contract if you were to blow up a balloon? A) diaphragm would contract, external intercostals would relax B) internal intercostals and abdominal muscles would contract C) external intercostals would contract and diaphragm would relax D) diaphragm contracts, internal intercostals would relax
Internal intercostals and abdominal muscles would contract.
The auditory tube drains into the...
Nasopharynx.
Atelectasis
Lung collapse due to plugged bronchioles, which leads to a collapsed alveoli OR wound that admits air into pleural cavity (pneumothorax)
Total lung capacity
Maximum amount of air contained in lungs after a maximum inspiratory effort.
Vital capacity
Maximum amount of air that can be expired after a maximum inspiratory effort.
Inspiratory capacity
Maximum amount of air that can be inspired after a normal expiration.
31) 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 WBCs.
Pharynx
Muscular tube that connects to the nasal cavity and mouth superiorly and larynx and esophagus inferiorly. The throat. From the base of the skull to the level of the 6th cervical vertebrae.
Is respiratory rate lowest in newborn infants?
Nope.
Lungs
Occupy all of the thoracic cavity except for the mediastinum. Left lung is smaller, separated into two lobes by an oblique fissure. Right lung has three lobes separated by oblique and horizontal fissures.
In the plasma, the quantity of oxygen in solution is....
Only about 1.5% of the oxygen carried in dissolved form.
Cartilage of larynx (paired and unpaired)
Paired: Arytenoid, cuneiform, corniculate Unpaired: Thyroid, cricoid, epiglottis
Laryngopharynx
Passageway for food and air - extends to larynx, where it is also continuous with the esophagus.
Oropharynx
Passageway for food and air from the level of the soft palate to the epiglotis.
Which center is located in the pons?
Pontine respirator group?
Atmospheric pressure
Pressure exerted by the air surrounding the body - 760 at sea level.
Interpleural pressure
Pressure in pleural cavity - fluctuates with breathing, but always negative or lungs would collapse.
Intrapulmonary pressure
Pressure within the aveoli - always eventually equalizes with atmospheric pressure. Positive on exhale.
Interpulmonary pressure is the...
Pressure within the aveoli of the lungs.
External respiration
Respiration at the level of lungs. Exchange between lungs and blood.
Internal respiration
Respiration at the tissue level - unloading from cells in capillaries. Exchange between systemic blood vessels and tissues.
Because the lungs are filled with fluid during fetal life, which of the following statements is true regarding respiratory exchange? A) Respiratory exchanges are made through the ductus arteriosus. B) Respiratory exchanges are not necessary. C) Respiratory exchanges are made through the placenta. D) Because the lungs develop later in gestation, fetuses do not need a mechanism for respiratory exchange.
Respiratory exchanges are made through the placenta.
Bronchea
Right main bronchus is wider, shorter, and more vertical than the left. Foreign objects usually go to right bronchus for this reason.
28) Which of the following is not a stimulus for breathing? A) rising carbon dioxide levels B) rising blood pressure C) arterial Po2 below 60 mm Hg D) arterial pH resulting from CO2 retention
Rising blood pressure.
Type II aveoli cell function
Secrete surfactant.
Respiratory zone
Site of gas exchange. Composed of respiratory bronchioles, alveolar ducts, and alveolar sacs (clusters of alveoli).
Boyle's law
The relationship between the pressure and volume of gas. Pressure varies inversely with volume
Inspiratory capacity is...
The total amount of air that can be inspired after a tidal expiration.
Nerve impulses from ____ will result in inspiration
The ventral respiratory group.
Possible causes of hypoxia include...
Too little oxygen in the atmosphere.
The lung volume that represents the total volume of exchangeable air is the ________.
Vital capacity
Functional residual capacity
Volume of air remaining in the lungs after a normal tidal volume expiration.
40) Factors that influence the rate and depth of breathing include ________. A) thalamic control B) voluntary cortical control C) stretch receptors in the alveoli D) composition of alveolar air
Voluntary cortical control
Trachea
Windpipe, from the larynx into the mediastinum.
Most inspired particles such as dust fail to reach the lungs because of the ________.
ciliated mucous lining in the nose
With the Bohr effect, more oxygen is released because a(n) ________.
decrease in pH (acidosis) weakens the hemoglobin-oxygen bond
Respiratory control centers are located in...
medulla and pons
Two factors on which expiration depends
the recoil of elastic fibers that were stretched during inspiration and the inward pull of surface tension due to the film of alveolar fluid
