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 ChangesDuring Ventilation

                  

    

                   

    

If you pretend that the balloons are lungs, and that the latex sheet on the bottom is the diaphragm……..

What happens when you What happens when you push the diaphragm up? 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) = VC – (TV + ERV)

Inspiratory Capacity (IC) = 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- HCO3- + H+OH-

(carbonic acid)

The respiratory system controls plasma levels of CO2 and thuscontrols plasma levels of H2CO3:

Hypoventilation leads to increased H2CO3 and decreased pH

and

Hyperventilation leads to decreased H2CO3 and increased pH