1. Respiratory System Pg. 428 - 435 & 636 - 637
Pg. 428 – & Pg

2. Respiratory System Function: RESPIRATION
- Exchange of gases between body & environment.
You INHALE & EXHALE approx. 16 – 24 X’s a minute.
You BREATHE more than 21,000 X’s in one day.
Pg. 428

3. RESPIRATION Two Phases of Respiration
External Respiration: Exchange of O2 & CO2 between AIR & BLOOD in lungs.
Lungs  O2  Blood
2. Internal Respiration: Exchange of gases between BLOOD & BODY cells.
Blood  O2  Cells
Cells  CO2  Blood
Pg. 428

4. Upper Respiratory Tract
Nose  Pharynx
Mouth & Nose - Air enters and exits your body.
Nostrils - hairs filter particles.
Nasal Cavity - warms & moistens air.
Cilia – Tiny hair-like structures
Trap particles & eliminates mucus from RS.
Mucus Membrane – Keeps passageways from drying out.
- Traps & removes foreign particles
- Dust, dirt, bacteria, viruses
Pg. 430

5. Upper Respiratory Tract
Sinuses - Air filled spaces above nose & throat.
Pharynx - (Throat) Two openings
1. Larynx – voice box
2. Esophagus – food tube
Pg. 430

6. Lower Respiratory Tract
Larynx  Lungs
Larynx – Voice box, connects pharynx to trachea.
- Vocal Chords: elastic tissue
- air passes between chords when you exhale.
- vibrations cause sound.
Epiglottis - flap of cartilage
- folds down to close off entrance to
larynx & trachea when you swallow.
Pg. 431

7. Lower Respiratory Tract
Trachea - Wind pipe (in front of esophagus)
- C – shaped rings of cartilage
to give strength.
- Serves as an air passage
between upper and lower tract.
- lining covered with mucus
and cilia.
Pg. 431

8. Lower Respiratory Tract
Bronchi - the airways that connect Trachea & Lungs.
Pg. 429

9. Lower Respiratory Tract
Alveoli - thin walled air sacs covered w/ capillaries.
- Gas exchange takes place here as O2 & CO diffuse across capillary walls.
Pg. 429

10. Lower Respiratory Tract
Lungs – Principle organ of the RS
Found w/in chest cavity
Protected by Ribs
Pg. 429

11. Lower Respiratory Tract
Diaphragm
Muscle that causes chest cavity to expand and contract.
Pg. 429

12. The Breathing Process INHALE:
Made possible by creating a pressure difference between the lungs and the outside of the body.
INHALE:
When lungs expand, pressure inside them becomes lower than the pressure outside body.
Air naturally flows into lungs to equalize the pressure.
Pg. 430

13. The Breathing Process EXHALE:
When lungs relax, pressure in lungs is higher than pressure outside your body.
Air naturally flows out of lungs to area of lower pressure.

14. Contract = Inhale Relax = Exhale
Pg. 429

15. Sequence For Respiration
Breathing  O2 inhaled
Circulation  O2 carried to cells
Respiration  O2 & Glucose combine in
a chemical reaction to release energy
Circulation  CO2 carried to lungs
Breathing  CO2 is exhaled