The respiratory system Flashcards
Define breathing rate
The number of breaths per minute
Define tidal volume
The volume of air inspired or expired per breath
Define minute ventilation
The volume of air inspired or expired per minute
Breathing equation
Breathing rate x Tidal volume = Minute ventilation
Mechanics of breathing-Inspiration at rest
-external intercostals and diaphragm contract and flattens
-ribs move up and out
-thoracic cavity volume increases
-pressure decreases
Mechanics of breathing-Expiration at rest
-External intercostals and diaphragm relax and returns to dome shape
-ribs move down and in
-thoracic cavity volume decreases
-pressure increases
Mechanics of breathing-Inspiration during exercise
-Sternocleidomastoid + pectoralis major
-ribs move up and out more
-thoracic cavity volume increases more
-pressure decreases more
Mechanics of breathing-Expiration during exercise
-Internal intercostals and rectus abdominals
-ribs move down and in more
-thoracic cavity volume decreases more
-pressure increases more
What is partial pressure?
pressure exerted by an individual gas held in a mixture of gases
Untrained values at rest
BR=12-15 b/min
TV=500ml
VE=6-7.5 l/min
Trained values at rest
BR=11-12 b/min
TV=500 ml
VE=5.5-6 l/min
Untrained values at maximal exercise
BR=40-50 b/min
TV=2.5-3 l
VE=100-150 l/min
Trained values at maximal exercise
BR=50-60 b/min
TV= 3-3.5 l/min
VE= 160-210 l/min