1. 3/17/08 Respiratory System Chapter 21 – Day 1

2. 3/17/08 Respiratory System Overview  Respiratory System Functions  Expulsion of CO 2  External vs. Internal Respiration  Organization – Upper & Lower  Pathway of O 2

3. 3/17/08 Respiratory System  O 2 delivery to cells is critical & the respiratory system makes it possible for O 2 from the atmosphere to enter the blood  Function ♦O 2 transport to the blood ♦CO 2 transport from the blood ♦Some role in speech (in terms of air movement)  Do we really breath out CO 2 ?  How does the body take in O 2 & expel CO 2 ?

4. 3/17/08  Special organs ♦Nose ♦Pharynx ♦Larynx ♦Trachea ♦Bronchi ♦Lungs - exchange of gases takes place here  Additional help comes from skeletal muscles Respiratory System Direct air into/out of lungs

5. 3/17/08 Process of Respiration  Physical movement of air ♦= External Respiration  Use of O 2 in cells for metabolism ♦= Internal/Cellular respiration

6. 3/17/08 Pathway of Air/ O 2  Nose – external nares → nasal cavity → internal nares   Pharynx – nasopharynx → oropharynx → laryngopharynx   Larynx – epiglottis → larynx   Trachea – trachea   Bronchi – primary bronchi → secondary bronchi → tertiary bronchi → bronchioles   Lungs – alveoli → blood stream

7. 3/17/08 Pathway of Air/ O 2  Each component is composed of special tissues which aid in their function  Passageways & accessory structures in the nose and pharynx = upper respiratory system  Nose: external & internal nose ♦Outside: cartilage & skin structure with 2 openings = external nares ♦Directs air into nasal passageways ♦External = object of “vanity’ “nose job” = Rhinoplasty – surgery to repair or alter nose structure – involves addition or removal of tissue Involves inconspicuous incisions & local anesthesia

8. 3/17/08 Pathway of Air/ O 2 - Skull  Nostrils lead into 2 chambers separated by the nasal septum  Right and left chambers of the nasal cavity  Walls of the nasal septum = ethmoid & vomer bones  Protrusions of the bone = nasal conchae (superior, middle, inferior) ♦Allows air to swirl in the nasal cavity – airborne particles get trapped in mucus ♦Cavity is lined with mucous membrane ♦Mucus is secreted by the paranasal sinuses (=air cavity with epithelium in the skull)  Floor of the nasal cavity = hard palate (roof of the mouth)

9. 3/17/08 Function of the Nose  Directs air into the nasal passageway  Warms air via blood circulation  Location for olfaction sensation  Traps particles & microbes = non-specific defense ♦These then get swallowed with mucous

10. 3/17/08 Pathway of Air/ O 2 – Pharynx and on  From the nasal cavity, air enters internal nares then the pharynx (throat)  Pharynx ♦Shared by digestive and respiratory systems ♦It is a muscular tube lined with mucous epithelium  Just behind the nasal cavity = nasopharynx

11. 3/17/08 Pathway of Air/ O 2  Nose – external nares → nasal cavity → internal nares   Pharynx – nasopharynx → oropharynx → laryngopharynx   Larynx – epiglottis → larynx   Trachea – trachea   Bronchi – primary bronchi → secondary bronchi → tertiary bronchi → bronchioles   Lungs – alveoli → blood stream

12. 3/17/08 Mechanics of Respiration  You will cover the details of aspects of the respiratory system in lab and lecture on Wednesday  For lab today you also need to be familiar with Pulmonary Ventilation (the fancy way to say “breathing”)  Air is pulled in & pushed out by a mechanical process ♦= ventilation ♦This process involves the diaphragm and skeletal muscles (intercostal muscles)  Breathing consists of 2 phases: ♦Inspiration air is taken into the lungs ♦Expiration Air passes out of the lungs

13. 3/17/08 Mechanics of Respiration  Air is moving in and out of the lungs due to pressure gradients  We will cover the mechanism in more detail in lecture, but be sure you read the introduction to each lab and to each section/activity…you will be responsible for the information presented there in lab and lecture!  Happy breathing