Biol 1152L Name ______
Respiratory System Handout Day & Lab time ______
Written by Nikki Sawyer
Pre-Lab Exercises – COMPLETE PRIOR TO LAB!
Exercise I: You should be familiar with the following terms before coming to lab. Look up the functions of each of the following structures.
Pharynx ______
What are the 3 regions of the pharynx? ______
Epiglottis ______
Arytenoid Cartilage ______
Thyroid Cartilage ______
Cricoid Cartilage______
Diaphragm ______
Vocal Folds ______
False Vocal Folds ______
Pre-Lab Exercise II: Answer the following questions.
1. Describe the branching of the bronchial tree, beginning with the trachea and ending with the bronchioles.
2. Describe the differences between the right and left lung.
3. Describe the blood flow through the pulmonary circuit.
In-Lab Exercise
I. Respiratory System Models
Identify the following structures on models and prepared dissections, using your textbook as a reference. Record the name of the structures of the model in Table 1.
1. Pharynx and Larynx 4. Lungs
a. Epiglottis a. Apex
b. Arytenoid cartilage b. Base
c. Thyroid cartilage c. Horizontal fissure
d. Cricoid cartilage d. Superior lobe
e. Trachea e. Middle lobe
f. Tracheal cartilages f. Inferior lobe
g. Vocal folds g. Oblique fissure
h. False vocal folds 5. Cardiopulmonary Structures
2. Esophagus a. Heart
3. Bronchial Tree b. Pulmonary arteries (right and left)
a. Bronchial cartilage c. Pulmonary veins (right and left)
b. Primary bronchus d. Pulmonary trunk
c. Secondary bronchus
d. Tertiary bronchus
e. Bronchioles
Table 1: Respiratory System Model Inventory
Model / Structures IdentifiedII. Lab Exercises: Sheep Lung Dissection
1. The lungs of a sheep are somewhat different than the lungs of a human. In sheep, the right lung is comprised of four lobes, while the left lung has three lobes.
2. On your specimen, locate the trachea and primary bronchus. Touch the lungs, trachea, and bronchus; notice the texture of the tissue. Pull on the trachea and note how elastic it is.
a. If the heart is still attached, identify the main blood vessels leaving and entering the lungs.
b. Identify any membrane surrounding the lungs.
3. Make a midsagittal cut down the trachea, separating the two lungs.
4. Choose one of the lungs and make a mid-coronal cut to separate the anterior portion of the lung from the posterior portion.
5. On the anterior portion of the lung, using scissors, cut along one primary bronchus, and continue a centimeter or more until you can see the opening of a secondary bronchus. How many secondary bronchi do you see on each side?
6. Cut along a secondary bronchus until you see the openings of tertiary bronchi. Is it possible to remove diseased portions of a lung, leaving other parts to inflate normally? Why or why not?
7. Cut a tertiary bronchus open. Do the airways opening along it contain cartilage? How do you know?
8. Cut out a piece of lung tissue. Would you say it is made of fine or coarse sponge? You will not be able to see the bronchioles, which are the site of an asthma attack.
Questions:
1. What structure allows the trachea to stay open yet still be able to bend?
2. Look at the two primary bronchi that branch off of the trachea. Is one bigger than the other? Explain your observations.
3. Are the lungs hollow bags or spongy? What does the lung tissue look like where you cut into it? What happens when you put this tissue into water?
4. In a living animal, what body movements draw air into the lungs? What body movements force air from the lungs?