1. The Respiratory System

2. System Overview
Includes tubes that remove particles from incoming air and transport air in and out of the lungs
Microscopic air sacs for gas exchange
Organs include:
Nose, nasal cavity, and paranasal sinuses
Pharynx
Larynx
Trachea
Bronchial tree
Lungs

3. Steps of Respiration
Respiration = the process of gas exchange between the atmosphere and body cells
Ventilation
External Respiration: Gas exchange between blood and air in lungs
Gas transport between lungs and body cells
Internal Respiration: Gas exchange between blood and body cells

4. Upper and Lower Respiratory Tracts
Upper Respiratory Tract
Organs located outside the thorax
Lower Respiratory Tract
Organs located within the thorax

5. The Nose Supported by bone and cartilage Nostrils Nasal cavity
Nasal septum
Nasal conchae
Support mucous membranes
Pseudostratified columnar epithelium and goblet cells
Extensive network of blood vessels to warm air

6. Paranasal Sinuses Air-filled spaces within: Reduce skull weight
Maxillary bones
Frontal bone
Ethmoid bone
Sphenoid bone
Reduce skull weight
Resonance chambers

7. Pharynx
Behind the oral cavity and between the nasal cavity and the larynx
Passageway for food and air
Helps produce speech

8. Larynx
AKA “Voice box”
Enlargement at the top of the trachea and below the pharynx
Conducts air in and out of the trachea
Prevents foreign objects from entering trachea
Houses vocal cords
Epiglottis

10. Vocal Cords
Horizontal folds of muscle and CT with a mucous membrane covering
False vocal cords
True vocal cords
Speech is formed by changing the shape of the pharynx and oral cavity
Words formed by the tongue and lips
Loudness
Pitch
Glottis
Steven Tyler Vocal Cords

11. Trachea
AKA windpipe
Extends in front of the esophagus and into the thoracic cavity
Splits into left and right bronchi
Ciliated epithelium and goblet cells
Filters incoming air
Sweeps particles out into pharynx
20 hyaline cartilage rings

12. Bronchial Tree Branched airways leading from trachea to lungs
Structurally similar to trachea with less cartilage
Mucous membranes filter incoming air and distribute air to alveoli

13. Passage of Air Though the Bronchial Tree
Primary bronchi  secondary bronchi  bronchioles  alveolar ducts  alveoli
Alveoli=air sac that exchange gases
creates surfactant fluid
Helps keep shape

14. Lungs Soft, spongy, cone-shaped organs in thoracic cavity
Lungs separated by the heart
Enclosed by thoracic cage and diaphragm
Suspended from bronchi and some large blood vessels
Right lung (3 lobes) is larger than left (2 lobes)
Visceral pleura
Hilus- entrance for blood vessels and bronchi (back of lungs)

15. Breathing Breathing consists of 2 processes: Inspiration (inhalation)
Expiration (exhalation)
Air moves into the lungs because of atmospheric pressure.
When lung pressure is lower than atmospheric pressure because of diaphragm and intercostal muscle contractions  inspiration
When muscles relax and lungs and thoracic cage return to normal size  expiration

16. How do Lungs work?

17. Control of Breathing Vital capacity=total amount of air in deep breath
Tidal Volume= normal breathing
Controlled by the respiratory center of the medulla oblongata and the pons
May also be affected by
Chemicals in body fluids (CO2, H+, O2)
Degree to which lung tissue stretches
Emotional state
Hyperventilation
Smoking
Control of Breathing

18. Incredible Human Machine Video