BIOL 2402, A&P II Laboratory
Minimum required structures and slides for:
Exercise 39: Respiratory System Physiology
A. Activity 1: Operating lung models:
Learning outcomes:
a. Describe the muscles and or forces involved in normal inspiration and
expiration.
b. Define a pneumothorax and explain how it may occur.
c. Identify the lobes, bronchi, and alveoli of the preserved wet and dried pig lung
specimens.
Procedures:
a. Follow directions in lab manual for simulating a pneumothorax with
the mechanical model.
b. Inflate preserved pig lung with a pump (usually set up on the side bench by
the windows). Put the lung back in the preservative fluid when not in use.
B. Activity 2: Auscultating respiratory sounds
Learning outcomes:
a. Identify the proper areas of auscultation of the lung and describe a normal
breath sound.
b. Distinguish the following abnormal sounds and their clinical significance
(1) Wheezing: high pitched sound due to narrowing of lower airway,
such as caused by asthma
(2) Crepitation (crackles): crackling or bubbling sound due to air
movement through alveolar fluid, such as caused by pneumonia
Procedures:
a. Following the instruction in your lab manual using a stethoscope, listen to the
lungs sounds of your own lungs or those of a partner. Clean ear pieces with
alcohol swab. Try to find the triangle of auscultation.
C. Activity 3: Spirometry (Measuring Respiratory Volumes and Capacities)
Procedures:
a. Investigate the respiratory volume of each at least two people in your
group by using the Lab Tutor Respiratory Air Flow & Volume computer
program. Use the disposable mouthpieces for this exercise and follow the
directions on the computer.
Learning Outcomes
a. Define the following lung volumes and capacities and identify them on a
diagram:
Tidal Volume (TV)
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Inspiratory Reserve Volume (IRV)
Expiratory Reserve Volume (ERV)
Vital Capacity (VC)
Residual Volume (RV)
Total Lung Capacity (TLC)
b. Compute the following lung capacities using the formulas below:
VC = TV + IRV + ERV
TLC = VC + RV
c. Define forced vital capacity (FVC) and forced expiratory volume one percent
[(FEV1%) FEV1% equals FVC exhaled in 1 second/FVC x 100]. Explain how these
measurements are used to distinguish obstructive* versus restrictive* lung
diseases or conditions.
*Obstructive lung diseases or conditions, such as asthma and bronchitis, reduce
FEV1% more than FVC because of narrowing of the airways. Restrictive lung
diseases or conditions, such as pregnancy or costochondritis, reduce FVC more
than FEV1% because of decreased lung volume.
D. Activities 4: Role of Respiratory System in Acid-Base Balance of Blood
Learning Outcomes
a. Write the formula for carbonic acid formation from CO2 in water.
b. Define a buffer, compare the buffering capacity of water with blood, and
describe what components in blood contribute to its buffering capacity.
Procedures: Follow the directions in the handout with the title, “Role of Respiratory
System in Acid-Base Balance of Blood”.
a. Supplies are at the front of the room on a cart—one basket per group.
b. It is mandatory to wear goggles when using the acids and bases. One drop of
concentrated HCS in the eye can cause permanent blindness!
c. Remember to remove probe cap from pH meters before using and calibrate
meters in standard buffer pH 7 with small screw driver.
d. Test tubes can be used in place of beakers for testing pH.
e. Sheep serum in refrigerator can be used in place of plasma.
f. Dispose of wastes in the marked containers in fume hood.
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