Respiratory 1 Flashcards
4 primary functions of respiratory system
- Exchange of gases between atmosphere and blood
- Homeostatic regulations of body pH
- Protection from inhaled pathogens and irritating substances
- Vocalization
By what mechanism does air exchange occur
Bulk flow
What principles does air exchange occur similar to CV system
- Flow from region of high to low pressure
- Muscular pump creates pressure gradients
- Resistance is influenced by diameter of tubes through which air is flowing
What is external respiration
Movement of gases between environment and cells within body
- all processes other than cellular respiration
What is the 4 steps of external respiration
Exchange 1: atmosphere to lung (ventilation)
2: lung to blood
3: transport of gases in the blood
4: blood to cells
What does external respiration require
Coordination between the respiratory and CV systems
- don’t want one working harder
3 structures involved in ventilation and gas exchange
- Conducting system or airways
- Bones and muscles of thorax
- Alveoli
What are muscles involved in ventilation
Sterocleidomastoids,scalenes, intercostals, diaphragm, abdominal
Upper airways
Nasal cavity, mouth, pharynx, larynx
What are lungs composed of
Light spongy tissue that is occupied mostly of air-filled spaces (alveoli filled with air)
Which lung is larger
Right lung: 3 lobes
Left lung: 2 lobes because cardiac notch for heart
What is each lung surrounded by
Double walled pleural sac
What are 2 parts of pleural sac surrounding lungs
Visceral pleura and parietal pleura
Visceral pleura
Connected to outside surface of lungs
Parietal pleura
Connected to inside surface of thoracic cavity
What exists between pleura layers
Fluid
What are functions of fluid between pleura
- created moist slippery surface (no friction)
- holds lungs tight to thoracic wall (they want to recoil but held together like two panes of glass with water between)
Stages of air flow
Nasal cavity/mouth -> pharynx-> larynx -> trachea -> primary bronchi -> smaller bronchi -> bronchioles -> alveoli
What is trachea
Semi flexible tube held open with 15-20 cartilage rings
How do airways follow similar branching to CV system
Every division 2 daughter airways have greater C.S.A. Than parent