Download CHAPTER 19: RESPIRATORY SYSTEM

CHAPTER 19: RESPIRATORY SYSTEM
OBJECTIVES:
1. Name the organs and functions of the respiratory system.
Organs
Functions
1. Nose/External Nares
1 exchange of gases
2 voice production
2. Nasal Cavity
3 blood pH homeostasis
3. Pharynx
4. Larynx
5. Trachea
6. Bronchial Tree within Lungs
7. Paranasal Sinuses
8. Diaphragm
2. Name the 5 parts of respiration (You will define these in later questions).
Pulmonary ventilation
External respiration
Transport of gases
Internal respiration
Cellular respiration
3.
Describe the significance of oxygen and carbon dioxide in human cells.
Oxygen is required by animal cells to perform cellular respiration which releases energy from
nutrients. A waste-product of CR is carbon dioxide.
3. Explain the structure and function of mucous membranes that line most of the
respiratory tract. Specifically name the tissue that lines the trachea.
Mucous membranes (mm) are moist membranes
that warm, moisten, and filter incoming air.
Goblet cells secrete mucus which protects.
Specifically in the trachea the mm is
pseudostratified columnar epithelium (PSCET),
where mucus coated cilia trap debris and cilia beat
debris up and out of airway.
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5.
Locate the upper respiratory organs on the diagram below, describe their structure
and any specific functions they may have (both respiratory and other functions, if
applicable).
All are lined by mucous membranes that warm, filter, and moisten incoming air. Nose
composed of bone and cartilage has macroscopic hairs to trap debris; nasal cavity is divided
into two by nasal septum and into three passageways on each side by nasal conchae;
paranasal sinuses are continuous with nasal cavity; pharyx is divided into nasopharynx,
oropharynx, and larynopharynx; larynx is composed of several hyaline cartilage components
and one elastic cartilage structure called the epiglottis. The larynx also contains vocal cords
producing
speech
6.
Name the four skull bones that contain sinuses and label them below.
Frontal, ethmoid, sphenoid, and maxillary
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7.
Name the three parts of the pharynx and label them in the diagram below.
Nasopharynx, oropharynx, and laryngopharynx
8.
Explain the significance of the epiglottis and glottis. Label the epiglottis above.
The epiglottis closes the airway during swallowing and the glottis is the slit-like space
between the vocal cords through which air passes
9.
Give the scientific name for the "Adam's Apple", and label it in the diagram below.
Thyroid cartilage
10.
Describe how and where sound originates and how it is then converted into
recognizable speech.
Sound originates when expelled air penetrates the vocal cords causing them to vibrate. The
cerebral cortex allows for speech initiation, and Broca’s areas stimulate the muscles necessary
for speech. The sinuses act as resonating chambers.
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11.
Locate the lower respiratory organs on the diagram below, and describe the structure
and any specific functions each may have.
Trachea’s hyaline cartilage supports airway and PSCET warms, filters and moistens with its
cilia; primary bronchi (to each lung), secondary bronchi (to each lobe) and tertiary bronchi
continue to warm….and distribute air
Terminal bronchioles are a regulation site determining the amount of air allowed into the
lung lobule; alveoli allow for gas exchange.
12.
Define the terms C-ring, trachealis muscle, and carina. Label carina above.
C-rings are named for the C shape of the rings of hyaline cartilage of trachea; the trachealis
muscle completes the C-ring anterior to the esophagus; carina is the point of bifurcation (i.e.
fork in the road) of the trachea into the lungs.
13.
Name the type of cartilage that composes the trachea wall. HYALINE CARTILAGE
14.
Distinguish between a primary, secondary, and tertiary bronchus, and label in the
diagram above.
Primary bronchi to each lung, secondary bronchi to each lobe and tertiary bronchi further
subdivide air.
15.
Explain what happens to the epithelial lining, cartilage and smooth muscle of the
bronchi as they branch deep into the lungs to form terminal bronchioles.
Epithelium is reduced to simple columnar ET, cartilage decreases and smooth muscle
increases.
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16.
Explain the effects that histamine and epinephrine have on terminal bronchioles.
Histamine causes bronchoconstriction; epinephrine causes bronchodilation
17.
Discuss the structure and function of the pleural membranes.
The visceral and parietal pleural membranes are serous membranes = simple squamous ET
over loose areolar connective tissue (LACT). The serous fluid (watery with high surface
tension) between them essentially glues the two membranes together and they act as one
which aids in inspiration.
18.
Distinguish between a lobe and lobule of the lung and label each on the diagram
below.
There are five lung lobes; three on the right and two on the left. There are many lung lobules
where each receives a respiratory bronchiole, is surrounded by elastic CT, and houses a
pulmonary artery and a pulmonary vein.
19.
Discuss the microscopic anatomy of the lung, and label the tissue components below.
The alveolar walls are composed of simple squamous ET plus its basement membrane.
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20.
Track a breath of air from the nose to an alveolus, noting what happens to the air as it
meets each structure (16 steps)
Nose
Secondary bronchus
Nasal cavity
Tertiary bronchus
Nasopharynx
Interlobular bronchiole
Oropharynx
Terminal bronchiole
Laryngopharynx
Respiratory bronchiole
Larynx
Alveolar duct
Trachea
Alveolar sac
Primary bronchus
Alveolus
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21.
Distinguish between Type I and Type II alveolar cells, in terms of structure and
function and label each in the diagram below.
Type I alveolar cells are the wall cells while type II secrete surfactant
22.
Define the term surfactant and describe its important function.
Surfactant, secreted by Type II alveolar cells is composed of phospholipids (fat,) and it
functions to reduce the surface tension during expiration, preventing recoiling of the
alveoli upon themselves.
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23.
a.
b.
c.
d.
The Anatomy & Physiology of the Respiratory Membrane (RM).
Draw a sketch of the RM, and label all parts (including specific tissue components
and membrane thickness).
Provide the scientific name of the scientific process that occurs through the RM, and
define that process.
Illustrate what occurs through this membrane using partial pressure values of gases
involved and arrows designating gas flow.
Finally, explain the fate of the transported gases involved.
Oxygen diffuses through the RM from the alveolus into the blood in the lung capillary
where it is transported back to the heart for distribution to the body, and carbon
dioxide diffuses through the RM from the blood in the lung capillary into the air in the
alveolus where it is expelled.
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24.
Define the term pulmonary ventilation, and describe its two actions in terms of
forces, muscles, and membranes involved.
Pulmonary ventilation is breathing. The two actions in pulmonary ventilation include
inspiration and expiration. Inspiration is due to atmospheric pressure and expiration is
due to elastic recoil. The diaphragm and intercostal muscles are involved.
25.
Starting with the diaphragm muscle in its relaxed position, describe in order,
the events that occur during inspiration.
1. The diaphragm contracts and pushes downward
2. The size of the thoracic cavity increases
3. The pressure within the thoracic cavity decreases to 758 mmHg (Boyle’s law)
4. Air rushes into and inflates the lungs (Dalton’s law)
26.
Explain how Boyle's Law relates to ventilation.
Boyle’s law states that the pressure of gas is inversely proportional to the volume of
the gas. As the size (volume) of the thoracic cavity increases, the pressure within the
thoracic cavity decreases to from 760 to 758 mm Hg.
27.
Explain why the serous fluid between the pleural membranes has such high
surface tension.
Serous fluid is composed primarily of water whose molecules are very cohesive
resulting in high surface tension.
28.
Define the term atelectasis, explain what is usually lacking within the alveoli
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when it occurs, and name the disease of premature newborns when it occurs.
Atelectasis is collapsed lung. Premature infants lack surfactant which functions to
overcome the high surface tension within the alveoli. This is called respiratory distress
syndrome.
29.
Name the instrument used to measure lung volumes.
Spirometer
30.
List, define, give estimate values, and correlate the six different lung volume
measurements shown in the graph below.
Tidal volume (TV) is the normal volume Vital capacity (VC) is TV + IRV + ERV
inspired and expired.
Inspiratory reserve volume (IRV) is the Residual volume (RV) is the volume of air
volume of air one can forcibly inhale after that always remains in the lungs.
a normal tidal inspiration.
Expiratory reserve volume (ERV) is the Total lung capacity is VC + RV.
volume of air one can forcibly exhale after
a normal tidal expiration.
31.
State Dalton's Law and explain its significance in respiration.
Dalton’ s law states that gases diffuse from where they are in high pressure to where
they are in low pressure. During inspiration, the pressure of the gas in the thoracic
cavity falls to 758 mm Hg, so air rushes from the outside where its pressure is 760 into
the alveoli.
32.
List the percentages of N2, O2, and CO2 in air.
Nitrogen = 78%; oxygen is 21%; and carbon dioxide is less than 1%.
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33.
Define what is meant by the partial pressure (pp) of a gas in a mixture and list
the pp values of O2 and CO2 in air and in the lung capillaries.
Air is a mixture of gases, which is 21% oxygen and less than 1% carbon dioxide. In a
mixture of gases, each gas exerts a partial pressure toward the total gas pressure, and
the partial pressure of a gas is directly proportional to its concentration. The partial
pressure of oxygen in the air in the alveolus is 104 mmHg and the partial pressure of
oxygen in the lung capillary is 40 mmHg. Consequently, oxygen diffuses through the
RM from the alveolus into the blood in the lung capillary where it is transported back
to the heart for distribution to all body cells. Conversely, the partial pressure of
carbon dioxide in the lung capillary is 45 mm Hg and the partial pressure of carbon
dioxide in the air in the alveolus is 40 mm Hg. Therefore carbon dioxide diffuses
through the RM from the blood in the lung capillary into the air in the alveolus where
it is then expelled.
34.
Discuss the factors that influence the rate at which a gas diffuses.
The factors that influence the rate at which a gas flows include: exchange surface
area, diffusion distance, and breathing rate and depth.
35.
Define the term internal respiration.
Internal respiration is the exchange of gases between the blood in the tissue
capillaries and the tissue cells.
36.
Discuss how oxygen and carbon dioxide are transported in the blood.
Oxygen is loosely carried by the hemoglobin in erythrocytes as oxyhemoglobin.
Most carbon dioxide (70%) is carried as bicarbonate ion; 23% is carried by hemoglobin
as carbaminohemoglobin, and 7% is diffused in the blood.
37.
Name the three factors that cause oxygen to be released from the hemoglobin
of red blood cells.
Oxygen is released by hemoglobin under the following conditions: increased
temperature; increased carbon dioxide concentration/pressure; decreased blood pH.
38.
Define the term hypoxia, and describe how it occurs during carbon monoxide
poisoning.
Hypoxia is a reduction of oxygen to cells. Because carbon monoxide is tightly bound to
hemoglobin, there are fewer hemoglobin molecules to carry oxygen.
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39.
Write the chemical equation that involves carbon dioxide, water, carbonic acid,
a hydrogen ion, and a bicarbonate ion, and explain its significance.
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40.
Locate the neural respiratory center on the diagram below.
Rhythmicity area is located in the
medulla. It is composed of a
dorsal respiratory group which
controls the basic rhythm of
breathing
and
a
ventral
respiratory group which controls
forceful breathing.
Pneumotaxic area is located in
the pons and controls rate of
breathing.
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41.
Explain how respiration is affected by varying chemical (CO 2 and O2)
concentration in the blood.
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