SILVERTHORN
CHAPTER 17 – MECHANICS OF BREATHING
THE RESPIRATORY SYSTEM
The four primary functions of the respiratory system are:
1. Exchange of gases between atmosphere and the blood
2. Homeostatic regulation of body pH
3. Protection from inhaled pathogens and irritating substances
4. Vocalization
The respiratory system (RS) is also a significant source of water loss and heat loss from the body.
The RS carries out these function by exchanging air between the environment and the interior
spaces of the lungs. This is the bulk flow of air:
– Flow goes from higher pressure to lower pressure
– Muscular pump creates pressure gradients
– Resistance of air flow is influenced by the diameter of tubes
Air is a less viscous, compressible mixture of gases while blood is a
non-compressible liquid.
Cellular respiration refers to the intracellular reaction of oxygen with
organic molecules to produce carbon dioxide, water and energy in the
form of ATP. External respiration is the movement of gases between
the environment and the body’s cells, and can be subdivided into four
integrated processes:
1. Ventilation (breathing). Inspiration & expiration
2. Exchange of O2 and CO2 between lungs and blood
3. Transport of O2 and CO2 by the blood
4. Exchange of gases between blood and cells
The RS consists of structures involved in ventilation and gas exchange:
1. The conducting system (airways)
2. Alveoli
3. Bones and muscles of the thorax (chest cavity) and abdomen
The RS can be divided into two parts: upper respiratory tract (mouth,
nasal cavity, pharynx and larynx) and lower respiratory tract/ thoracic
portion (trachea, two primary bronchi, their branches and the lungs).
Bones and muscles of the thorax surround the lungs
Two sets of intercostal muscles, internal and external, connect the 12
pair of ribs. Additional muscles, the sternocleidomastoids and
scalenes, run from the head and neck to the sternum and first two ribs.
The pericardial sac contains the heart, and the two pleural sacs
surround a lung.
Kort de anatomie van de longen:
Silverthorn – chapter 17: Mechanics of breathing Page 1 of 10
CHAPTER 17 – MECHANICS OF BREATHING
THE RESPIRATORY SYSTEM
The four primary functions of the respiratory system are:
1. Exchange of gases between atmosphere and the blood
2. Homeostatic regulation of body pH
3. Protection from inhaled pathogens and irritating substances
4. Vocalization
The respiratory system (RS) is also a significant source of water loss and heat loss from the body.
The RS carries out these function by exchanging air between the environment and the interior
spaces of the lungs. This is the bulk flow of air:
– Flow goes from higher pressure to lower pressure
– Muscular pump creates pressure gradients
– Resistance of air flow is influenced by the diameter of tubes
Air is a less viscous, compressible mixture of gases while blood is a
non-compressible liquid.
Cellular respiration refers to the intracellular reaction of oxygen with
organic molecules to produce carbon dioxide, water and energy in the
form of ATP. External respiration is the movement of gases between
the environment and the body’s cells, and can be subdivided into four
integrated processes:
1. Ventilation (breathing). Inspiration & expiration
2. Exchange of O2 and CO2 between lungs and blood
3. Transport of O2 and CO2 by the blood
4. Exchange of gases between blood and cells
The RS consists of structures involved in ventilation and gas exchange:
1. The conducting system (airways)
2. Alveoli
3. Bones and muscles of the thorax (chest cavity) and abdomen
The RS can be divided into two parts: upper respiratory tract (mouth,
nasal cavity, pharynx and larynx) and lower respiratory tract/ thoracic
portion (trachea, two primary bronchi, their branches and the lungs).
Bones and muscles of the thorax surround the lungs
Two sets of intercostal muscles, internal and external, connect the 12
pair of ribs. Additional muscles, the sternocleidomastoids and
scalenes, run from the head and neck to the sternum and first two ribs.
The pericardial sac contains the heart, and the two pleural sacs
surround a lung.
Kort de anatomie van de longen:
Silverthorn – chapter 17: Mechanics of breathing Page 1 of 10
