1. Respiratory System
Unit 4

2. Ventilation [Breathing]- the act of moving air in/out of the lungs
Respiration- process where ventilation occurs along with the exchange of gases in the lungs and the body tissues

3. Types of Respiration
External Respiration
-exchange of gases between air in lungs and blood [alveoli and pulm. capillaries]
Internal Respiration
-exchange of gases between the blood stream
and body’s tissues

5. Upper Respiratory Tract Organs - Nose, Nasal Cavity, Sinuses, Pharynx
Lower Respiratory Tract Organs - Larynx, Trachea, Bronchi, Lungs, Bronchial Tree, Alveoli

7. Upper Respiratory Tract
Nose
made of bone and cartilage
nares/nostrils-openings guarded by hairs that filter
Nasal Cavity
-divided sagitally by nasal septum
-lined with mucous membrane
Warms air
Moistens air
Traps particles

9. Nasal Conchae [superior, middle, inferior turbinate]
-bony, scroll like projections on lateral wall of each cavity
-increase surface area inside [helps mucous membrane]
-channel and speed up airflow through nose
Sinuses[paranasal]
-air filled hollow spaces inside 4 bones of skull
[ethmoid, sphenoid, maxillary and frontal bones]
- positioned around nose
-lined with mucous membrane
Drain fluids into nasal cavity
Decrease weight of skull
Resonate the voice

14. Pharynx [throat]
-3 regions: Nasopharynx-posterior to nasal cavity
Oropharynx-posterior to oral cavity
Laryngopharynx- posterior to larynx [voicebox]
*Pseudostratified ciliated epithelial tissue lines most of tract.
Cilia encourages flow of mucous
-trapped particles travel down esophagus into stomach

16. Lower Respiratory Tract
Larynx [voicebox]
-walls made of cartilage
-Thyroid cartilage [adam’s apple]
-Epiglottic cartilage- covered with mucous membrane
-epiglottis blocks opening to trachea [glottis] when
swallowing
False Vocal cords- musc/conn. tissue; same function as epiglottis
True Vocal cords- musc/elastic fibers; vibrate with air passage; helps form words

20. Trachea [windpipe]
-Anterior to esophagus
-4-5 inches long
-Connects larynx to thoracic cavity
-Divides inferiorly at an area called the carina, into R and L primary bronchi (each lung)
-Lined w/ciliated mucous membrane
-Made of “C”-shaped cartilage rings allowing for expansion of esophagus when consuming food
-Also smooth muscle

24. Primary bronchi lead into the lungs and divide to form the bronchial tree Primary bronchi  secondary bronchi tertiary bronchi bronchioles alveolar ducts  alveoli

25. Lungs [Right and Left] -Right – 3 lobes (upper, middle, lower)
– divided by 2 fissures (horizontal b/w upper and middle lobes; oblique fissure b/w middle and lower)
-Left - 2 lobes (upper, lower)
– divide by oblique fissure. Lung is slightly smaller to accommodate space for the heart

27. Pleural Cavity
-double-layered membrane covering
-visceral pleura: inner layer on the lung surface
-parietal pleura: outer layer lines the inside of the thoracic cavity
-space in b/w the pleural layers filled with serous fluid to reduce friction as lungs inflate and deflate.
Pleurisy- infection of the pleural layers. Reduced serous fluid and increased friction when breathing

29. -Serous fluid creates surface tension b/w the pleural layers
-keeps them adhered to each other
-essential for keeping the lungs inflated.
When the outer pleural membrane (parietal pl.) moves outward because it is attached to the thoracic wall ,the inner pleural layer (visceral pl.) moves with it.
Pneumothorax: air gets in the pleural space
Atelectasis: too much air gets in the pleural space disrupting surface tension b/w the pleural layers and causes collapsed lung.