Respiratory system 3 Flashcards
What makes up the thoracic cavity
Mediastinum (Heart, vessels and pericardium) Pleural cavities (lungs)
How is ventilation driven
Changed in pressure of the thoracic cavity
What is the relationship between pressure and volume
Pressure is inversely proportional to volume. P=1/V
If vol increases, pressure decreases
How is pressure measured
By collisions
How do we breath
By establish a pressure gradient.
What is the gradient when we breath in
Increased volume inside the lungs (decreased pressure)
What is the gradient when we breath out
Decreased volume inside the lungs (increased pressure)
What are the joints in the ribs
Sternocostal (between cartilage and sternum) - Synovial (1st cartilaginous)
Costochondral (between cartilage and rib) - Cartilaginous
Interchondral (between cartilage) - synovial
What is the costotransverse and the costovertebral
Costotransverse - between rib and transverse vertebrae
Costovertebral - between rib and body of vertebrae
What is the articulation between vertebrae and ribs
Synovial joint
What are the primary inspiratory muscles
Diaphragm
Intercostals
When are the accessory muscles used
Only activated when needed
Describe the diaphragm
Skeletal muscle separates thorax from abdomen Relaxed - dome shaped Contracted - Flattened Contraction expands thoracic cavity and compresses abdominopelvic cavity
Describe the intercostal muscles
Attached diagonally between ribs
External - Lifts ribcage expands cavity - inspiration
Internal - depresses ribs and deceases cavity (forced)
What is quiet and forced breathing
Quiet - normal breathing
Forced - when talking/needing more oxygen
