1. RESPIRATORY SYSTEM
STRUCTURE

2. LOOK AT FIGURE 17-2 pg 355

3. NASAL CAVITY Nose Nasal septum divides nose into R and L sides
Both sides are lined with ___________ membranes
Cilia – hairs in nose that trap dirt and particles

4. SINUSES Cavities in skull filled with air
Frontal, maxillary, sphenoid, and ethmoid
Connected to nasal cavity by ducts
Lined with mucous membrane
Helps to warm and moisten air passing through them
Give resonance to the voice
SEE FIGURE 17-3 pg 355

5. PHARYNX Throat Serves as a common passageway for air and food 5” long
Can be subdivided into:
Nasopharynx
Oropharynx
laryngopharynx

6. LARYNX Voice box Triangular chamber below pharynx
Composed of nine fibrocartilaginous plates
Adams apple – largest of the plates
Contains vocal cords
Become larger in males during puberty which makes Adams apple more prominent
Lined with mucous membrane
Epiglottis – flap of cartilage that covers larynx during swallowing
SEE FIGURE 17-4 pg 356

7. TRACHEA
Windpipe
Tubelike passageway that extends from the larynx, passes in front of esophagus, and continues to form the 2 bronchi
4 ½” long
Walls have bands of C-shaped cartilage
Lined with ciliated mucous membrane
FIGURE 17-4

8. BRONCHI AND BRONCHIOLES
Lower end of trachea divides into R and L bronchus
Right bronchus is shorter, wider, and more vertical
Become bronchial tubes and bronchioles as branches enter lungs
FIGURE 17-5 pg 358

9. ALVEOLI
Clusters of thin-walled sacs made of single layer epithelial tissue
Inner surfaces covered with surfactant
What does surfactant do?
Each alveolus surrounded by capillaries
Why?
FIGURE 17-5

10. LUNGS Fill thoracic cavity Upper part = apex Lower part = base
Lung tissue porous and spongy, it floats
Due to alveoli and air it contains
R lung larger and broader but shorter, 3 lobes (superior, middle, and inferior)
L lung smaller, narrower, and longer, has 2 lobes (superior and inferior)
FIGURE 17-6 pg 359

11. PLEURA
Membrane that covers lungs (thin, moist, and slippery tough endothelial cells)
Double-walled sac
Space is pleural cavity
Pleural cavity filled with pleural fluid to prevent friction

12. MEDIASTINUM Interpleural space
Between lungs along the medial plane of the thorax and extends from the sternum to vertebrae
Contains the thoracic viscera