RESPIRATORY SYSTEM PHYSIOLOGY

Richland College
Biol. 2402
Marieb A&P Lab Manual - 11 th Edition
RESPIRATORY SYSTEM PHYSIOLOGY
OBJECTIVES
1. To define the various capacities and volumes used in spirometry.
2. To use a dry spirometer and understand which spirometry values can be determined.
3. To correlate the bell bar model with the lungs, and to understand the simulation of inspiration
and expiration.
4. To locate the skeletal muscles involved in normal breathing and how their
contraction/relaxation changes the rib cage size.
5. To describe how changes in carbon dioxide affect your breathing rate and your ability to hold
the breath.
6. To explain the relationship between carbon dioxide and carbonic acid, and to describe how
one can qualitate exhaled carbon dioxide in a solution.
ACTIVITY 1: OPERATING THE MODEL LUNG
Use of the balloon-bell jar to illustrate expiration and inspiration
Understand the parts of the body that correspond to parts on the bell jar model.
ACTIVITY 2: RESPIRATORY SOUNDS
normal sounds
ACTIVITY 3: MEASURING RESPIRATORY VOLUMES - Procedure A only
use of DRY spirometer (nonrecording spirometer) in determining:
tidal volume (average of 3 breaths)
expiratory reserve volume
vital capacity (NOTE: charts on predicted vital capacities for male/female)
Mathematically determine inspiratory reserve volume by formula, knowing above values.
SKIP the section on the Recording (wet) Spirometer. INSTEAD, we will use the DIGITAL
RECORDING SPIROMETER to demonstrate various spirometry volumes.
SKIP ACTIVITIES 4-6 covering the wet sprirometer and BIOPAC
ACTIVITY 7: THE REACTION BETWEEN CARBON DIOXIDE AND WATER
Understand the role of respiratory system in acid-base balance (explained p. 148).
Describe the reaction of carbon dioxide with water, the formation of carbonic acid, and its dissociation.
We are NOT going to perform the exercise in the lab book, but rather the 2 exercises following
this sheet (Effect of Carbon Dioxide on Breath-holding and The Effect of Exercise on the Rate of
Carbon Dioxide Production.
SKIP ACTIVITIES 7-9: CARBON DIOXIDE AND PH
NOTE:
Interactive Physiology CD or access to www.interactivephysiology.com
INTERACTIVE PHYSIOLOGY RESPIRATORY SYSTEM – Excellent review!

Richland College
Biol. 2402
Marieb A&P Lab Manual - 11 th Edition
THE EFFECT OF EXERCISE ON THE RATE OF CARBON DIOXIDE PRODUCTION
Phenolphthalein is a pH indicator. If a solution is alkaline, the phenolpthalein will produce a
purple color. If a solution is neutral to acid, it becomes colorless.
This experiment will show the effects of exercise on CO2 production. As expired air is bubbled
through an alkaline solution, the CO2 in your breath will dissolve in the solution and produce
carbonic acid, changing the pH of the solution from alkaline to neutral, thus from purple to
colorless. The time required for this color change to occur is dependent on the amount of CO2
expelled. Higher levels of CO2 will change the colored solution faster. In this experiment, you
will perform the test resting and then repeat the experiment after exercising.
Note the amount of time required for the color change in the solution to take place. THE SAME
PERSON NEEDS TO BLOW INTO THE FLASK EACH TIME.
1. Add 50ml of 0.01% NaOH (sodium hydroxide) solution to each of 2 flasks.
2. Add 2-3 drops of phenolpthalein to each flask.
3. Take a straw, place it INTO solution and blow continuously into one of the flasks until the
solution loses its color. The color will change gradually, and may even be difficult to tell
whether clear or not. It may help to hold a white piece of paper behind the flask to tell
subtle color changes.
4. Note the time required for the solution to become colorless on the chart.
5. Now run in place for approximately 2 minutes. Afterwards, blow continuously into the
flask solution.
6. Indicate the time required for the solution to become colorless on the chart.
7. RINSE BOTH FLASKS WITH DISTILLED WATER AND RETURN TO THE LAB TRAY.
TIME REQUIRED - RESTING EXHALATION
TIME REQUIRED - POST-EXERCISE EXHALATION
minutes
minutes
QUESTIONS:
1. What color does the solution turn when becoming basic?
2. In which situation was more carbon dioxide produced? WHY?
3. What is the purpose of the phenolpthalein?
4. What is the purpose of the NaOH?
5. Why/how does CO2 acidify the solution?

THE EFFECTS OF CARBON DIOXIDE ON BREATH HOLDING
All 3 tests should be run on the SAME SUBJECT.
NORMAL BREATHING
1. The subject breathes NORMALLY. Be sure that the subject does not exaggerate his/her
breathing, but breathes in a normal pattern. A lab partner will determine your respiratory rate by
counting the number of breaths per minute.
2. The subject now takes the deepest possible breath and HOLDS it. The lab partner will time
the breath-holding from the beginning to end.
3. Record the respiratory rate and breath-holding time below.
Breathing rate : ______ breaths/minute
Duration of breath-holding: ______ seconds
BREATHING INTO A PAPER BAG
1. The subject will breathe into a paper bag for 2 minutes. Be sure that the bag is closed
tighly around the nose and mouth by holding the hands against the face.
2. Determine the subject's respiratory rate and record below.
3. The subject will now take the biggest possible breath from the paper bag and hold the breath
for as long as possible.
4. Time the duration of this breath-holding and record below.
Breathing rate : ______ breaths/minute
Duration of breath-holding: ______ seconds
HYPERVENTILATION
BE SURE THAT THE SUBJECT IS SITTING DOWN FOR THIS TEST.
1. The subject will hyperventilate (deep, rapid breathing) for 30 seconds to1 minute. If you
begin to get dizzy, stop hyperventilating.
2. The subject will now take the biggest possible breath and hold for as long as possible.
3. Time the duration of this breath-holding and record below.
4. The subject will once again hyperventilate for 30 seconds to a minute, and then breathe
normally. The lab partner will note the respiratory rate during this time.
5. Determine the subject's respiratory rate and record below.
Breathing rate : ______ breaths/minute
Duration of breath-holding: ______ seconds
QUESTIONS:
1. In which situation were you able to hold your breath the least amount of time? WHY?
2. In which situation were you able to hold your breath the longest amount of time? WHY?
3. What happened to the respiratory rate after hyperventilation? WHY?