THE RESPIRATORY SYSTEM

I. HISTOLOGY: 
   A. Lung Slide:  Such slides are difficult to prepare due to the delicate nature of the alveolar sacs and alveolar ducts. The elastic lung tissue forms very thin walls of smaller airways and air sacs. These walls often become distorted or broken during the preparation process. Scan the entire slide to find an area relatively intact and compare what you see to the photographs and diagrams in your text and lab atlas.
 
        You should see simple squamous walls around "empty" spaces. These spaces are the alveoli and can be of a variety of shapes depending upon the angle of the slice through the tissue. You may find a cross-section of a larger airway showing cartilage or smooth muscle in its wall and a pseudostratified ciliated columnar epithelial lining. These are terminal bronchioles. You may also see cross sections of pulmonary blood vessels. Try to distinguish between artery and vein.
 
   B. Trachea slide: (human or other mammal):  The trachea provides examples of several tissue types.  It is a major airway (the "windpipe").  Its lumen has to be supported open so that air may pass through.  It has a lining with the special functions of moistening and cleaning the entering air.  It has to be flexible and resilient.

      1. Hyaline cartilage rings which support the trachea are observed as oval fields or patches of evenly stained matrix.  The chondrocytes (cartilage cells) are isolated in scattered spaces called lacunae (lakes) which often appear white* (empty) after the staining procedures. The cartilage is found deep to the epithelial lining, fibrous connective tissue, and smooth muscle.

      2. The epithelial lining is pseudostratified ciliated columnar epithelium and may demonstrate goblet cells.
          Search for the  free border of cells on your slide, center them, and change to high power.
         (a) Use the fine focus knob to determine the presence of cilia.
         (b) Try to notice whether the cells are all connected to the basement membrane. 
              (They are, but may not appear to be.)
         (c) If you see clear, rounded, or protein-filled cells interspersed among the columnar cells,
               these are the goblet cells and their product (staining blue/purple if present) is mucus.

      3. As to the presence of other tissues, the slides vary in the amounts of fibrous connective, smooth muscle, or adipose tissue which may be observed.  Adipose cells are very large and appear white (empty) as the stored lipid contained within the cell was rinsed out during preparation.  The very little cytoplasm is pushed to the cell membrane, as is the  nucleus.  List all the types of tissues you can identify in your slide.

FOR THE PRACTICAL BE ABLE TO RECOGNIZE THE STRUCTURES IN BOLD PRINT ABOVE.

II. GROSS ANATOMY. 

 

FOR THE PRACTICAL, BE ABLE TO RECOGNIZE AND CORRECTLY NAME THE  STRUCTURES LISTED BELOW.  Recognize and identify the following on the models and sheep pluck (if possible): Respiratory models: model 1, model 2, model 3, model 4, model 5, model 6, model 7, model 8, model 9, model 10, model 11 and model 12
   

   A. nares

        1. internal nare

        2. external nare

    B. nasal cavity
        1. superior conchae

        2. middle conchae

        3. inferior conchae
    C. hard and soft palates
    D. cribriform plate

    E. pharynx
        1. nasopharynx
        2. oropharynx 
        3. laryngopharynx 
    F. tonsils
        1. pharyngeal tonsil
        2. palatine tonsils
        3. lingual tonsil
    G. uvula
    H. tongue
    I. esophagus
    J. larynx
        1. epiglottis
        2. glottis
        3. true and false vocal cords
        4. hyoid bone
        5. cricoid cartilage   
        6. thyroid cartilage
        7. arytenoid cartilages
        8. laryngeal prominence
        9. thyrohyoid membrane
    K. trachea
    L. bronchi
        1. primary bronchi and site of Carina
        2. secondary bronchi
        3. tertiary bronchi

        4. terminal bronchiole

        5. respiratory bronchioles

        6. there are 23 orders of branches 
    M. thoracic cavity
        1. external and internal intercostal muscles
        2. parietal and visceral pleura
        3. diaphragm
    N. right and left lung
        1. apex, base
        2. surfaces
            a. costal surface 
            b. mediastinal surface
            c. diaphragmatic surface
        3. lobes (5 total)
            a. right lung: superior lobe, middle lobe, inferior lobe
            b. left lung: superior lobe, inferior lobe
        4. fissures 
            a. right lung: horizontal, oblique
            b. left lung: oblique
        5. cardiac notch
        6. pulmonary hilus   
    O. right and left pulmonary blood vessels
    

    P. Cat dissection:  Photo1 Photo2 Photo3

  1. Larynx
  2. Trachea within mediastinum
  3. Right Lung (cranial,  middle, caudal, accessory lobes)
  4. Left Lung (cranial, middle, caudal lobes)
  5. Diaphragm
  6. Parietal Pleura
  7. Visceral Pleura

III. PHYSIOLOGY

     A. Use the stethoscope against a partner's chest and dorsal rib cage to listen for respiratory sounds.

     B. Take a resting respiratory rate for your partner by counting respirations (one inspiration and one expiration equal one respiration) for one full minute. The average respiratory rate is 12-18 respirations per minute.

     C. Have your partner step in place or ride an exercise bike for three full minutes, then take another respiratory rate.  Did the rate change?  Did you notice any change in the depth of respirations?
 
     D. Using the spirometer available, determine your vital capacity Diagram 1, Diagram 2, Diagram 3
          (1)  Obtain a fresh mouthpiece for the spirometer.
          (2)  If using the hand-held spirometer, turn the silver dial so that the red "0" mark is at the needle.  If using the wet spirometer, make sure the bell is empty of air and move the indicator to "0" on the scale.
          (3)  Breathe in as deeply as you can, even using all the accessory muscle power available to you.
          (4)  Hold your nose (so that air will not escape) and blow forcefully into the spirometer, using accessory expiration  muscles, until you have no air to expel.
          (5)  Read the number on the scale (in ml).
          (6)  The value you read is your vital capacity; that is, the total amount of air you can exchange using your inspiratory  reserve volume, tidal volume, and expiratory reserve volume.  3-4 liters (3000-4000 ml) is a typical healthy vital capacity.

FOR THE PRACTICAL, BE ABLE TO IDENTIFY AND NAME THE SPIROMETER, DEMONSTRATE AN UNDERSTANDING OF THE TERM "VITAL CAPACITY", CALCULATE A RESPIRATORY RATE AND MATHEMATICALLY DETERMINE ALL CAPACITIES AND VOLUMES GIVEN A SET OF NUMBERS.

IV.  WEBSITES