BIOL 204 Lab For Week 9
Respiratory System Physiology and
Histology
Objective 1
Trachea - Histology
Identify the pseudostratified ciliated epithelium, the hyaline
cartilage and smooth muscle (if visible)
Tracheal Epithelium
A lower magnification – tracheal cartilage
Objective 2
Lung Tissue
Identify bronchioles, alveolar sacs, alveolar ducts, bronchi and
alveoli
Can You Tell The Difference?????
Objective 3
Pressure/Volume Changes
During Ventilation
If you pretend that the balloons are lungs, and that the latex
sheet on the bottom is the diaphragm……..
What happens when you
push the diaphragm up?
What happens when you
pull the diaphragm down?
Objective 4, 5 and 6
Spirometry
Can be used to measure lung volumes and calculate lung capacities
A Hand Held Spirometer
is used to measure
1. tidal volume (TV)
2. expiratory reserve
volume (ERV)
3. vital capacity (VC)
Use these values to calculate:
Minute Respiratory Volume (MRV) = Tidal Volume X respirations/Minute
Inspiratory Reserve Volume (IRV)
Inspiratory Capacity (IC)
= VC – (TV + ERV)
=
TV + IRV
Predicted Vital Capacity
Males
=
0.052 (height) – 0.022 (age) – 3.60
Females
=
0.041 (height) - 0.018 (age) - 2.69
VC = vital capacity in liters
H = height in centimeters
A = age in years
average measured VC
% of predicted vital capacity
=
X 100
predicted value (from tables)
Objective 7
Acid Base Balance
Plasma buffers exist to maintain plasma pH between 7.35 and 7.45
NaHCO3 (sodium bicarbonate) buffers H+ and prevents acid fluctuations:
NaHCO3 + H+
HHCO3 + Na+
(sodium bicarbonate)
H2CO3 (carbonic acid) buffers OH- and prevents alkaline fluctuations:
H2CO3 + OH(carbonic acid)
HCO3- + H+OH-
The respiratory system controls plasma levels of CO2 and thus
controls plasma levels of H2CO3:
Hypoventilation leads to increased H2CO3 and decreased pH
and
Hyperventilation leads to decreased H2CO3 and increased pH