1. RESPIRATORY SYTEM
Anatomy & Physiology

2. BACKGROUND-Cellular Respiration
Oxygen is used by cells
Oxygen is needed to convert glucose to ATP
Carbon dioxide is a waste product
Body cells die if respiration fails

3. FUNCTIONS Supplies body with oxygen and removes carbon dioxide
Filters, warms, and humidifies air
Helps with producing sound
Regulates blood pH

4. DIVISIONS OF THE RESPIRATORY SYSTEM
Upper respiratory tract
Nose/nasal cavity/sinuses/pharynx/larynx
Lower respiratory tract
Trachea/bronchial tree/lungs

5. STRUCTURES/ORGANS Conducting Zone- passages that let air in
Respiratory Zone- gas exchange
Larynx- voice box; made of cartilage; false and true vocal cords; attached to hyoid bone
Speech
Breathing airway
Switching mechanism for food and air→ epiglottis

7. Structures/organs
Trachea- windpipe; smooth cartilage with C shaped rings that divides into 2 bronchi; flexible but does not collapse despite pressure changes
Bronchi- tubes enter lungs; branch into microscopic alveolar ducts that end in sacs
Lungs- extend from diaphragm to clavicle; lobes (2 left lobs and 3 right lobes)
Alveoli- site of gas exchange

9. STRUCTURES/ORGANS
Nose- airway; moisten and warms air; filters; resonating chamber for speech; olfactory receptors; nasal cavity=floor=palate (anterior is hard and posterior is soft)
Paranasal sinus- open into nasal; lighten the skull; infection=sinusitis
Pharynx- throat; houses tonsils; 3 parts (naso,oro,laryngo);
uvula closes nasopharynx (no food in the nose)

10. RESPIRATORY MUCOSA Goblet cells
Secrete mucus; watery fluid with lysozyme
Produce about a quart a day of liquid with dead junk (dead junk is swallowed)

11. GAS EXCHANGE
Air fills alveoli and accounts for most of the lung volume (1500 sq feet)
Wall of alveoli→ 2 cell thick (thinner than tissue paper); external wall is covered with cobweb of capillaries
air/blood barrier- gas exchange; oxygen diffuses from air in alveoli to blood in capillaries; carbon dioxide diffuses from blood (capillaries) into alveoli
Moves from a high to low concentration through diffusion

12. RESPIRATION INCLUDES:
Pulmonary ventilation- replaces gases
External respiration- gas exchange in the lungs
Transport- gases by the blood and heart
Internal respiration- gas exchange into the tissues

14. VENTILATION Breathing is pulmonary ventilation 2 phases
Inspiration- inhalation of air/air goes in
Diaphragm flattens when contracted (high height of thoracic cavity)
Intercostal muscles contract to raise the ribs (increases circumference of the thoracic cavity, keeps thorax stiff so sides don’t collapse)
Expiration- exhalation of air/air goes out
Rib cage drops under the force of gravity
Relaxed diaphragm → moves up (curved shape)
Volume decreases which increases the pressure  

15. Ventilation Mechanical forces causes movement of air
Gases flow from high to low pressure
Diaphragm and intercostal muscles accomplish this
Pressure is established by changes in the thoracic cavity
High (size) thorax → low pressure = air moves in
Low (size) thorax → high pressure = air moves out

16. VOLUMES OF AIR EXCHANGE
Vital capacity: largest volume of air a person can move in and out
Depends on the size of the cavity, posture, diseases/condition