Anatomy & Physiology Lecture
Chapter 22 - Respiratory System
I.
Overview
A. Introduction
B. Conducting Passages
C. Pulmonary Alveoli, Lungs, & Pleurae
D. Mechanics of Breathing
E. Regulation of Breathing
II. Introduction to the Respiratory System
A. The major role of this system is to supply body tissues with ______ and dispose of
_____________ (gas exchange)
B. _______________ refers to 4 main functions
1. ____________ ventilation - breathing
2. ___________ respiration - gas exchanges between the air & blood at the lung alveoli
3. ____________ of respiratory gases via the circulatory system
4. ____________ respiration – gas exchange between cells & capillaries; oxygen is
needed for cellular respiration
C. The respiratory system can be divided ___________ into upper & lower divisions, and
_____________ into a conducting & a respiratory division
D. Basic Structure of the Respiratory System
1. Major ________ & structures of the respiratory system are the
a. __________ respiratory - nasal cavity, pharynx, larynx, and trachea superior to the
lungs
b. __________ respiratory - bronchi, bronchioles, and pulmonary alveoli within the
lungs
2. Air passes from nasal cavity  pharynx  larynx  ________  bronchi 
bronchioles  ________
3. The _________ division includes all the cavities and structures that transport gases to
& from the pulmonary alveoli; called the anatomical ______ space because no gas
exchange occurs here
4. The ____________ division consists of the pulmonary _______, which are the
functional units of the respiratory system, where gas exchange between the air and
blood occur
III. __________ Passages - transport air to the lungs; passages are lined with epithelia that
cleanse, warm, and humidify the air
A. Nose - includes an external portion, the external ______, that opens to an internal nasal
cavity, the nasal ___________
1. The _________ cavity is formed by the following skull bones
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a. Roof - frontal & ________ bones
b. Medially – the nasal _________ formed by the perpendicular plate of the ethmoid,
vomer, & septal cartilage
c. Posteriorly - _________ bone
d. Floor – ______ palate, formed by the palatine & maxillary bones, and muscular
_______ palate
e. Lateral walls have 3 bony projections: the superior, middle, and inferior nasal
________ (turbinates)
2. The conchae are lined with pseudostratified ________ columnar epithelium that
contain mucus-secreting goblet cells
3. Nasal _______ in the nostrils filter inhaled macroparticles
4. The main function of the nasal cavity is to ______, moisten, and filter the inspired air
a. Debris from air is trapped in the _______
b. _____ move the mucus to the pharynx, where it is swallowed
5. ____________ is an inflammation of the nasal mucosa.
B. ___________ Sinuses - connect with the nasal cavity via drainage ducts. These paired
sinuses include the ______:
1. ________
2. _________
3. __________
4. ___________
5. ____________ is an inflammation of these sinuses.
C. ___________ (throat) is divided into 3 regions:
1. _______pharynx - uppermost pharynx, behind the nasal cavity and above the soft
palate; contains the
a. _________ - hangs from the middle part of the soft palate; both block the nasal
cavity during swallowing
b. __________ tubes - connect the nasopharynx with the middle ear cavities
c. Pharyngeal tonsils (__________) are found in the posterior wall of the nasal
cavity
2. ____pharynx - mid-pharynx between the soft palate and hyoid bone; contains paired
a. _________ tonsils on the posterior lateral wall; often become infected and are
removed during a tonsillectomy
b. _________ tonsils on the base of the tongue
3. _________pharynx - posterior pharynx extends downward from the hyoid bone and
opens into the esophagus & larynx.
a. Food goes into the __________
b. Air moves through the ________ into the larynx and trachea
D. ________ (“voice box”) - in anterior midline of the neck at C4-C6
1. The larynx prevents food from entering the _________ and produces sound
2. It is composed of 9 _________: 3 large unpaired and 6 smaller paired structures
a. _______ cartilage - large, unpaired, anterior structure with a laryngeal
prominence (_______ apple)
b. ___________ - composed of elastic cartilage, located behind the root of the tongue;
during swallowing, it folds over the ______ opening to the larynx
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c. ________ cartilage - ring shaped base of larynx; connects thyroid cartilage to the
trachea
d. ________ cartilages - paired above the cricoid and behind the thyroid; posterior
attachments of the vocal folds
e. Cunieform & ___________ cartilages - paired, small accessory structures
associated with the arytenoid cartilages
3. Two pairs of strong CT _____ are stretched between the thyroid & arytenoid cartilages
a. _______ folds (true vocal cords) - vibrate to produce sound
b. _________ folds (false vocal cords) - support the vocal folds, but do not produce
sound
4. Laryngeal __________ include
a. _________ muscles - elevate the larynx during swallowing
b. __________ muscles - change length, position, & tension of the vocal folds
5. ____________ is an inflammation of the larynx
E. __________ (windpipe)
1. Rigid tube anterior to the _________; connects the larynx to the primary bronchi
2. 16-20 anterior hyaline cartilage ________ form the supporting walls of the trachea
3. The trachea mucosal lining consists of _______stratified ciliated columnar epithelium
with many ______ cells; ________ move particles trapped in mucus out of the lungs
4. __________ – surgical incision into the trachea below the larynx to bypass a blockage
or crushed larynx
F. Bronchial _______ - respiratory tubes branch into progressively narrower tubes as they
extend into the lungs in the following order:
1. L. & R. __________ bronchi
2. Secondary (_________) bronchi
3. Tertiary (__________) bronchi
4. __________
5. __________ bronchioles
6. ____________ bronchioles
7. Alveolar _______
8. Alveolar ______
9. Pulmonary __________
G. Smooth ________ in the bronchi walls is affected by the parasympathetic and sympathetic
nervous systems
1. Broncho_________ occurs when parasympathetic nerves or _________ constrict
bronchioles, leading to decreased air flow
2. Broncho__________ occurs when __________, released by the adrenal gland during
exercise or stress, dilates bronchioles, leading to increased air flow
IV. Pulmonary Alveoli, Lungs, & Pluera
A. Pulmonary Alveoli
1. Alveolar sacs are clusters of tiny pulmonary __________, the functional units of the
respiratory system. Alveolar cells are
a. Type __ – simple _________ epithelium surrounded by a basal lamina, forming a
thin respiratory membrane, AND
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b. Type ___ – __________ epithelium that secretes lubricating ____________ that
keeps alveoli from sticking together
2. _____ exchange occurs between the alveoli and their associated capillaries
a. ________ diffuses across the alveoli walls into the capillaries
b. _____ diffuses from the capillaries into the alveoli
B. ________ - paired respiratory organs lateral to the mediastinum and surrounded by the rib
cage within the thoracic cavity
1. Each lung has 4 _________:
a. __________ (medial) surface - slightly concave and contains a verticle slit, the
_______ through which pulmonary vessels, nerves, & bronchi pass
b. ______ - concave inferior surface that fits over the diaphragm
c. ______ - pointed, superior surface that extends above the clavicle
d. __________ surface - rounded lateral surface in contact with the membranes
covering the lungs
2. Right & left lungs are similar, but have some ___________:
a. ______ lung has a _______ notch on its medial surface and is divided by a single
fissure into a superior and inferior lobe
b. _____ lung is divided by ____ fissures into superior, middle, and inferior lobes.
c. Each lobe is further divided into many smaller _________, which contain the
pulmonary alveoli
C. ________ - serous membranes that surround the lungs and line the thoracic cavity include
the
1. ________ pleura adheres to the outer lung surface and extends into the interlobular
fissures
2. ________ pleura lines the thoracic cavity and the mediastinum, thus both lungs are in
separate compartments
3. A pleural ________ is found between the visceral & parietal pleura; ________ fluid in
this cavity allows the membranes to slide across each other during respiration
4. _______ is an inflammation of the pleura, which causes friction between the pleural
membranes and makes breathing difficult
V. Mechanics of Breathing
A. Pulmonary ___________ (breathing) consists of two phases: inspiration (inhaling) and
expiration (exhaling)
B. Relaxed _____________ involves contractions of the diaphragm, external & internal
intercostal muscles
1. Contraction of the dome-shaped ___________ (stimulated by the _________ nerve)
causes it to flatten, increasing lung volume;
2. Simultaneous contractions of the __________ intercostals (stimulated by __________
nerves) lift the ribs, further increasing lung volume
a. _______ Law – the pressure of a quantity of gas is inversely proportional to the
volume of its container (P1/V)
b. During inspiration alveolar volume ___________, which ___________
intrapulmonary pressure below atmospheric pressure (760 mm Hg  757 mm
Hg)
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c. Because atmospheric pressure is now higher than intrapulmonary pressure, air
flows _______ the lungs
d. ____________ pressure (≈754 mm Hg) - the pressure in the pleural cavity is
always more negative than the intrapulmonary pressure; this acts as a suction to
keep lungs inflated
e. ____________ is a condition in which the lung(s) collapse if air enters the pleural
cavity.
C. __________ inspiration involves contractions of the scalenes and sternocleidomastoid
muscles, which further elevate the ribs
D. Relaxed __________ - muscles of inspiration _______, ribs return to their original
position; lung internal volume decreases, causing intrapulmonary pressure to increase, so
air moves _____ of lungs
1. __________ is a lipoprotein produced by type II alveolar cells; it reduces alveolar
_________ tension, allowing the alveoli to recoil during expiration
2. Premature infants are often deficient in surfactant, which causes hyaline membrane
disease (___________ Distress Syndrome)
E. During _________ expiration, internal intercostals and abdominal muscles contract in
response to intercostal and lower spinal nerves
F. Measurements of Ventilation can be obtained via a __________, which captures expired
air and records the rate and depth of breathing, speed of expiration, and rate of oxygen
consumption. Measurements are respiratory volumes or respiratory capacities
1. Tidal volume (___) - amount of air inhaled or exhaled normally in one respiratory
cycle (____ mL)
2. Inspiratory reserve volume (_____) – amount of air above the tidal volume that can
be inhaled with maximum effort (______ mL)
3. Expiratory reserve volume (_____) – amount of air above the tidal volume that can
be exhaled with maximum effort (______ mL)
4. Residual volume (___) – amount of air left in lungs after maximum expiration
(_______ mL)
5. Vital capacity – amount of air that can be exhaled with maximum effort after
maximum inspiration (___ = TV + IRV + ERV) (________ mL)
6. Total lung capacity (____) – total volume of air the lungs can hold (______ mL)
7. Forced expiratory volume (____) – percent of the vital capacity that can be exhaled in
a given time interval.
a. Healthy adults should be able to expel ___-___% of the vital capacity in one
second.
b. Inability to do so may indicate respiratory _________
VI. Regulation of Breathing
A. The three respiratory _________ of the brain are the
1. ___________ area in the medulla __________ contains nerve cell bodies that form the
inspiratory and expiratory portions
2. Apneustic & pneumotaxic areas in the _____ influence the activity of the rhythmicity
area
a. ___________ center promotes inspiration
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b. _____________ (pontine respiratory group) center inhibits inspiratory neurons
B. Two groups of _______________ respond to changes in blood chemistry
1. ________ chemoreceptors in the ____ sense a change in blood ____ and initiate
changes to restore homeostasis
a. High CO2 (___________) stimulates hyperventilation to remove excess CO2
b. Low CO2 (___________) lowers ventilation to restore CO2 levels
2. ____________ chemoreceptors in the aorta and carotid arteries sense a decrease in
blood oxygen levels
a. _________ bodies send sensory information to the MO in the ________ nerves
b. __________ bodies stimulate sensory fibers in the _________pharyngeal nerves,
which signal the MO
VII. Respiratory Conditions
A. Developmental Problems
1. ____________ - genetic disorder which causes an over secretion of thick mucus that
clogs respiratory passages and allows bacteria to infect the lungs
B. Trauma or Injury Problems
1. Choking - foreign object lodges in the trachea; may be dislodged by the __________
maneuver
C. Respiratory Disorders
1. _____________ - acute infection & inflammation of the lung accompanied by fluid
buildup; may be bacterial, fungal, or viral
2. _______________ - inflammatory lung disease contracted by inhaling Mycobacterium
tuberculosis bacteria from a carrier
3. ___________ - caused by allergy to inhaled antigens; causes a swelling or blockage of
lower respiratory tubes
4. Chronic _________ – often found in smokers, tobacco smoke paralyzes and
eventually destroys _______ and alveolar macrophages; excess mucus production
leads to coughing and infection
5. ____________ - causes the breakdown of the pulmonary _____, increasing the size of
air spaces and decreasing their surface area; frequent cause of death among smokers.
D. Lung _________, which causes 1/3 of all cancer deaths in the U.S., is caused mostly by
tobacco smoke, which contains numerous carcinogenic compounds
1. Three forms of lung cancer are __________ cell carcinoma, adenocarcinoma, and
small-cell carcinoma
2. Symptoms include chronic coughing and ______ in the sputum
3. Lung cancer ____________ so rapidly, it has usually spread to other organs by the time
it is diagnosed, and prognosis is poor