1. The Respiratory System
Human Biology
The Respiratory System

2. Organs of the Respiratory system
Nose
Pharynx
Larynx
Trachea
Bronchi
Lungs – alveoli
Conducting pathways
Gas exchange

3. Function of the Respiratory System
Gas exchange between the blood and external environment
Exchange of gasses takes place within the lungs in the alveoli
Conducting Passageways: purify, warm, and humidify the incoming air

4. Nose and Nasal Cavity
The nose and nasal passage way contain lots of veins very close to their surface.
Warms air entering body
Also has sticky mucous layer that traps debris and bacteria
Nasal cavity

5. Pharynx (Throat) Muscular passage from nasal cavity to larynx
Common passageways for air and food
Phayrnx

6. Larynx (Voice Box) Routes air and food into proper channels
Plays a role in speech
Made of eight rigid hyaline cartilages and a spoon-shaped flap of elastic cartilage (epiglottis)
Larynx

7. Structures of the Larynx
Thyroid cartilage
Largest hyaline cartilage
(Adam’s apple)
Epiglottis
Covers the trachea when swallowing forcing food into the esophagus
Vocal cords (vocal folds)
Vibrate with expelled air to create sound (speech)
Glottis – opening between vocal cords

8. Trachea (Windpipe) Connects larynx with bronchi
Lined with ciliated mucosa
Expel mucus loaded with dust and other debris away from lungs
Walls are reinforced with C-shaped hyaline cartilage
Bronchus
Trachea

9. Lungs
The lung is the essential respiration organ in air-breathing vertebrates. Its principal function is to transport oxygen from the atmosphere into the bloodstream, and to excrete carbon dioxide from the bloodstream into the atmosphere. This exchange of gases is accomplished in the mosaic of specialized cells that form millions of tiny, exceptionally thin-walled air sacs called alveoli. The lungs also have nonrespiratory functions.

11. Bronchioles Smallest branches of the bronchi
Alveoli: Small air sacs where gasses are exchanged

12. Alveoli
Gas exchange takes place within the alveoli in the respiratory membrane
Single layer of squamous epithelial cells
Allows for rapid diffusion of gasses

13. Alveoli Alveoli are surrounded by capillaries
Gasses are exchanged between the air inside the alveoli and the blood in the capilaries
High concentration of O2 in the alveoli
Low concetration of O2 in the blood
Low conentration of CO2 in the alveoli
High concentration of CO2 in the blood

14. Grab a sheet of paper!
Put the following organs of the respiratory system in order without your notes.
Larynx
Nose
Pharynx
Lungs
Trachea
Bronchi