1. Human Respiratory System
Upper Respiratory Tract
Nasal cavity
Pharynx
Lower Respiratory Tract
Larynx
Epiglottis
Vocal cords
Trachea
Bronchi
Lungs
Bronchioles
Alveoli
The nose opens into the nasal cavity. Hairs and cilia in the nose screen out debris. Air moving in through the nose, trachea, and bronchi is filtered, warmed, and moistened. Cilia in the trachea and bronchi beat upward to carry mucus, dust, and occasional bits of food into the throat, where the sputum is swallowed or expelled.
Air reaching the lungs is at body temperature and saturated with water.

2. Upper Respiratory Tract
Functions
Olfaction
Filter, warm, and moisten air
Resonating chamber
Cartilage differences are the main reason why people have different shaped noses, although the shape of the nasal bones can determine the slope of the nose itself.
The nasal cavities are separated from the mouth by the hard and soft palates.
The air and food passages cross in the pharynx, with danger of choking if food enters the trachea by accident.
This arrangement is good because it allows mouth breathing when the nose is plugged or when more air is needed during heavy exercise.
The pharynx
The 2 eustachian tubes open into the upper part of the pharynx. When food is swallowed, the glottis is closed by a flap of tissue called the epiglottis, and backward movement of the soft palate covers the entrances to the nasal passages so that food enters the esophagus.
The larynx
The larynx is a short passageway that connects the pharynx to the trachea. This is where the glottis and vocal cords can be found. The glottis is attached to elastic ligaments called the vocal cords, which vibrate to produce sound when air is moved out past them. The larynx is held open permanently by complex cartilage that forms the Adam's apple, and it is inside this structure that the vocal cords can be found. Larger in males than in females due to the actions of testosterone.

3. URT: Nose External nares (nostrils) Nasal vestibule Nasal cavity
PCCE, mucus
Warms and filters
Olfaction
Turbinates (conchae)
Internal nares
Nasopharynx
Hard palate
Soft palate
The nasal cavity is a large air-filled space above and behind the nose in the middle of the face. The nasal cavity is important in warming and cleaning the air as it is inhaled. The nasal cavity also contains organs involved in olfaction.
The nasal cavity is enclosed by the nasal bone above and by the maxilla and ethmoid bone on the sides. The palate separates the nasal cavity from the mouth. To the front of the nasal cavity is the nose, while the back is continuous with the pharynx. The paranasal sinuses are connected to the nasal cavity through small orifices called ostia.
The nasal cavity is divided in two by a vertical fin called the nasal septum. On the sides of the nasal cavity are three horizontal outgrowths called turbinates or conchae (singular "concha"). These turbinates disrupt the airflow, directing air toward the olfactory epithelium on the surface of the turbinates and the septum.
Cilia and mucus along the inside wall of the nasal cavity trap and remove dust and germs from the air as it flows through the nasal cavity. The cilia move the mucus down the nasal cavity to the pharynx, where it can be swallowed.
There is a rich blood supply to the nasal cavity. In some animals, such as dogs, the capillary beds flowing through the nasal cavity help cool the blood flow to the brain.

4. URT: Pharynx Functions 3 anatomical regions: Nasopharynx Oropharynx
Passageway for air and food
Resonating chamber
Houses tonsils
3 anatomical regions:
Nasopharynx
Eustachian tubes
Oropharynx
Common passageway for food/water and air
Laryngopharynx
Epiglottis
Remember the upper respiratory tract’s function is to filter, warm, and humidify the air we breathe.

6. Lower Respiratory Tract
Functions:
Vocalization
Exchange gases for respiration and pH control

7. Larynx Superior border: laryngopharynx Posterior border: esophagus
Inferior border: trachea
Stratified squamous epithelium
PCCE inferior to vocal cords
Nine cartilages

8. Laryngeal Cartilages Epiglottis Thyroid Cricoid Arytenoid (2)
Elastic cartilage
Thyroid
Thyrohyoid membrane
Laryngeal prominence
Hyaline cartilage
Cricoid
Cricothyroid ligament
Hyaline, complete ring
Arytenoid (2)
Vocal ligaments
Corniculate (2)
Cuneiform (2)
Aryepiglottic fold
Thyroid cartilage growth is stimulated by testosterone; reason why “Adam’s apple” is larger in males.
Cricoid is narrow anteriorly, but wid in posterior to support larynx.
The cuneiform cartilages don’t attach to the others; held in aryepiglottic fold (false vocal cord, lateral fold next to corniculate cartilages

9. Trachea Larynx to L and R bronchi C-shaped cartilage
Why?
Annular ligaments
Trachealis muscle and ligamentous membrane
PCCE
The trachea is held open by a series of C-shaped cartilaginous rings with the open part facing the back. Not complete so as to allow for changes in diameter due to heavy breathing or coughing. From the trachea, air passes into 2 bronchi that enter the right and left lungs
The trachea is lined with epithelial tissue that has goblet cells and cilia to trap and move debris out of the lungs. What type is it? (PCCE)
The trachea branches into two bronchi.

10. Lungs Cardiac notch – heart makes left lung 10% smaller than right
Separated from each other by the heart
Each lung enclosed by double-layered pleural membrane
Parietal pleura – lines wall of thoracic cavity
Visceral pleura – covers lungs themselves
Pleural cavity is space between layers
Pleural fluid reduces friction, produces surface tension (stick together)
Cardiac notch – heart makes left lung 10% smaller than right

11. Lungs Apex Base Costal surface (lateral) Mediastinal surface (medial)
Parenchyma
CT trabeculae
Septa (lobules)
Parenchyma means the tissue characteristic of an organ.

12. Lung Lobes Right Left Superior Middle Inferior Cardiac notch
Horizontal fissure
Middle
Oblique fissure
Inferior
Left
Cardiac notch

13. Alveoli
Alveolar sacs are made up of tiny bulges called alveoli and it is inside the alveoli that gas exchange takes place. Our lungs contain about 100 million alveoli with a total surface area of 750 to 800 square feet. By comparison, the total surface area of our skin is 15 to 20 square feet. The wall of each alveoli is only one cell layer thick and is surrounded by capillaries. There are certain epithelial cells inside the alveoli that secrete a substance called a surfactant, which helps to reduce the surface tension inside each alveolus.
Gas exchange