1. The Respiratory System
Fall 2017
Anatomy and Physiology lab II
Dr. Santos

2. Upper respiratory tract- consists of the passages superior to the thoracic cavity
Lower respiratory tract- within the thoracic cavity
Conducting zone- passages that carry air to the lower respiratory passages where gas exchange takes place.
Respiratory zone- passages in which gas exchange occurs.

4. General structure of the respiratory system
Respiratory tract- Series of highly branching passages that conducts air to the structures of gas exchange.
Parietal pleura- Outer layer of the pleural membrane that lines the interior of the thoracic cavity and the superior surface of the diaphragm.
Visceral pleura- Inner layer of the pleural membrane that adheres tightly to the lung.
Pleural cavity- Very thin potential space between the parietal and visceral pleura that contains a thin layer of serous fluid.
Lungs and lobes- Lungs are organs composed of elastic connective tissue and tiny air sacs called alveoli. Each lung is divided into sections (three in the right lung and two in the left lung) called lobes.

5. Right lobes- (upper, middle and lower)
Left lobes- (upper and lower)
Fissures-deep indentations that separate the lobes.
Horizontal fissure-separates right upper lobe and right middle lobe
Right oblique fissure-separates the right middle and right lower lobe
Left oblique fissure- separates the left upper lobe and left lower lobe

6. Structures of the Respiratory Tract
Nasal cavity- Area within the skull framed by cartilage and bone that extends from the anterior nares to the posterior nares; filters, warms, and moistens inhaled air.
Pharynx- The area located posterior to the nasal cavity (the nasopharynx), the oral cavity (the oropharynx), and the larynx (the laryngopharynx)
Larynx Cartilage-framed region of the respiratory tract within the neck that houses the vocal cords
Trachea -Portion of the respiratory tract in the inferior neck and superior mediastinum that connects the larynx with the bronchial tree
Primary bronchi- The initial branches off the trachea that each serve one lung
Secondary bronchi- Branches off the primary bronchi that each serve one lobe of the lung
Terminal bronchioles Passageways smaller than 0.5 mm in diameter that control airflow to the structures for gas exchange

7. Respiratory bronchioles- Small branches off the terminal bronchioles that have alveoli in their walls
Alveolar ducts- Portion of the respiratory bronchiole made up exclusively of alveoli
Alveoli- Terminal structures of the respiratory tract; consist primarily of thin simple squamous epithelium through which gases are exchanged with the blood

9. Larynx

10. Air passes from the pharynx to the larynx, a short passage framed by 9 cartilages.
The lid- is a piece of elastic cartilage known as the epiglottis
The thyroid cartilage- a large cartilage that forms the anterior and lateral walls of the larynx
Cricoid cartilage- inferior to the thyroid cartilage
Cricothyroid ligament- a soft ligament between the thyroid and cricoid cartilage
Laryngeal prominence- “Adam's apple”

11. “Voice box” Common name for larynx
Vocal folds/cords- 2 sets of elastic ligaments
Superior set (false vocal cords)- play no role in sound production but serve sphincter function)
Inferior set- they vibrate as air passes over it to produce sound.

12. Passage of air
Start: nasal cavity ➜ nasopharynx ➜ oropharynx ➜ laryngopharynx ➜ larynx ➜ trachea ➜ primary bronchus ➜ secondary bronchus ➜ tertiary bronchus ➜ multiple smaller bronchi ➜ bronchiole ➜ terminal bronchiole ➜ respiratory bronchiole ➜ alveolar duct ➜ alveolus End

13. 21.3 Lung inflation
Cricrothyroidotomy- procedure used to unblock the air passageway
1- Place an incision in the cricothyroid ligament (soft spot)
2- insert a tube into the opening
3- ventilate patient artificially
THIS RESTORES THE PATIENT’S AIRWAY BY BYPASSING THE UPPER RESPIRATORY SYSTEM.