The respiratory system provides for exchange of oxygen and carbon dioxide of the body.
- In terrestrial vertebrae’s, the respiratory system includes 3 steps:
1. Breathing: Inspiration (inhaling oxygen) and Expiration (exhaling carbon dioxide)
2. External exchange- Gas exchange between the AIR and BLOOD in lungs. Blood then transfers oxygen to the tissue cells.
3. Internal exchange- Gas exchange between the BLOOD & TISSUE FLUID and between the CELLS & TISSUE FLUID. Blood then transfers carbon dioxide to the lungs.
- The respiratory system is involved in production of sound.
- Respiratory system helps regulate blood pH.
The respiratory system structure - includes all of the structures that conduct air in a continuous pathway to and from the lungs.
Respiratory system is divided into two tracts:
Upper Respiratory Tract
Consist of:
Nasal Cavities- One or two canals in the nose, separated by a septum.
Lined with hair, cilia, and goblet cells that make up mucus and filters the air from air-dust, pollen and foreign materials.
Pharynx- Common passageway for both food intake and air movement.
Larynx- Voice Box, Contains the vocal chord. Located between the pharynx and the trachea.
Lower Respiratory Tract
Consist of:
Trachea- Air tube (windpipe) that runs between the larynx and the bronchi.
Bronchi- Branch of the trachea that leads to the lungs
Bronchioles- Small tube that conducts air from a bronchus to the alveoli.
Lungs- Respiratory organ containing moist surfaces for gas exchange
Alveoli- Terminal, microscopic, grape like air sac in the lungs. The pulmonary artery and pulmonary vein surround it. The alveolus is directly responsible for the exchange of oxygen and carbon dioxide.
Neural Control of Breathing Rate
The Brain regulates breathing rate by controlling contraction of the rib cage muscles and the diaphragm.
Increase concentrations of hydrogen ions (H+) and carbon dioxide (CO2) in the blood are the primary