BIO 202 PhysioEx Lab Report Exercise 7: Respiratory System Mechanics Activity 1: Measuring Respiratory Volumes and Calculating Capacities

2/20/26, 2:08 PM PhysioEx Exercise 7 Activity 1



PhysioEx Lab Report
Exercise 7: Respiratory System Mechanics
Activity 1: Measuring Respiratory Volumes and Calculating Capacities
Name: Morris
Date: 20 February 2026
Session ID:

Pre-lab Quiz Results
You scored 100% by answering 5 out of 5 questions correctly.

1 Which of the following statements describing the mechanics of breathing is false?

You correctly answered: Ventilation relies exclusively on contracting skeletal muscles.

2 The contraction of which of the following muscles will increase the thoracic cavity volume
during inspiration?

You correctly answered: the external intercostals.

3 At the beginning of inspiration, the

You correctly answered: thoracic cavity volume increases.

4 At the beginning of expiration, the

You correctly answered: pressure in the thoracic cavity increases.

5 A tidal volume refers to the

You correctly answered: amount of air inspired and then expired with each breath under
resting conditions.


Experiment Results
Predict Question
1 Predict Question: Lung diseases are often classified as obstructive or restrictive. An
obstructive disease affects airflow, and a restrictive disease usually reduces volumes and
capacities. Although they are not diagnostic, pulmonary function tests such as forced
expiratory volume (FEV1) can help a clinician determine the difference between obstructive
and restrictive diseases. Specifically, an FEV1 is the forced volume expired in 1 second.




https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex7/act1/ 1/6

, 2/20/26, 2:08 PM PhysioEx Exercise 7 Activity 1

In obstructive diseases such as chronic bronchitis and asthma, airway radius is decreased.
Thus, FEV1 will

Your answer: decrease proportionately.

Stop & Think Questions
1 Which muscles contract during quiet expiration?

You correctly answered: none of these muscles contract during quiet expiration.

2 Minute ventilation is the amount of air that flows into and then out of the lungs in a
minute. Minute ventilation (ml/min) = TV (ml/breath) x BPM (breaths/min).


Using the values from the second recorded measurement, enter the minute ventilation.

You answered: 7500 ml/min.

3 A useful way to express FEV1 is as a percentage of the forced vital capacity (FVC). Using the
FEV1 and FVC values from the data grid, calculate the FEV1 (%) by dividing the FEV1 volume by
the FVC volume (in this case, the VC is equal to the FVC) and multiply by 100%.


Enter the FEV1 (%) for an airway radius of 5.00 mm.

You answered: 73.9 %.

4 A useful way to express FEV1 is as a percentage of the forced vital capacity (FVC). Using the
FEV1 and FVC values from the data grid, calculate the FEV1 (%) by dividing the FEV1 volume by
the FVC volume (in this case, the VC is equal to the FVC) and multiply by 100%.


Enter the FEV1 (%) for an airway radius of 3.00 mm.

You answered: 70.2 %.

Experiment Data

Radius Flow TV (ml) ERV IRV RV VC FEV1 TLC BPM
(mm) (ml/min) (ml) (ml) (ml) (ml) (ml) (ml)
5.00 7485 499 ---- --- --- --- --- --- 15
5.00 7500 500 1200 3091 1200 4791 3541 5991 15
4.50 4920 328 787 2028 1613 3143 2303 4756 15
4.00 3075 205 492 1266 1908 1962 1422 3871 15
3.50 1800 120 288 742 2112 1150 822 3262 15
3.00 975 65 156 401 2244 621 436 2865 15



https://media.pearsoncmg.com/bc/bc_0media_ap/physioex/10/ex7/act1/ 2/6