The Mechanics Of Breathing Flashcards
What is the primary principle governing the movement of air during breathing?
Air moves from high pressure to low pressure via diffusion.
What pressure condition is necessary for inspiration to occur?
Pressure in the lungs must be lower than in the atmosphere.
What pressure condition is necessary for expiration to occur?
Pressure in the lungs must be higher than in the atmosphere.
How does increasing the volume of the thoracic cavity affect lung pressure?
It reduces the pressure of air in the lungs.
How does decreasing the volume of the thoracic cavity affect lung pressure?
It increases the pressure of air in the lungs.
What causes the pressure changes in the lungs during breathing?
The contraction of muscles.
Name the muscles used for inspiration during rest.
- Diaphragm
- External intercostals
Name additional muscles used for inspiration during exercise.
- Sternocleidomastoid
- Scalenes
- Pectoralis minor
What muscles are involved in passive expiration at rest?
Diaphragm and external intercostals just relax.
Name the muscles used during active expiration.
- Internal intercostals
- Abdominals
Fill in the blank: To inhale, the diaphragm _______.
[contracts and is pulled flat]
Fill in the blank: During exhalation, the diaphragm _______.
[relaxes and rises to dome-shaped position]
True or False: The ribcage moves upwards and outwards during inhalation.
True.
True or False: The ribcage falls during inhalation.
False.