Respiratory Cycle / Quiet breath: End of expiration (end of the cycle)
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At the end of expiration...

The chest wall has outward elasticity. When the inward elasticity of the lungs balances with the outward elasticity of the chest wall, expiration ends. Naturally, the negative pleural pressure and lung volume are at their minimum (within a quiet breath).
When the lung volume ceases to decrease, pressure inside the lungs (alveolar pressure) becomes equal to the atmospheric pressure and the gas outflow (expiration) ceases.

This is the same illustration as in "quiet breath:When the respiratory muscles are relaxed and there is no respiratory movement". Again, the diaphragm contracts and the cycle is repeated.

Achievement Quiz
At the end of expiration, the diaphragm is 1 [ A contracting / B relaxing ].
At the end of expiration, the lung volume is 2 [ A at its minimum / B increasing from its minimum to its maximum / C at its maximum / D decreasing from its maximum to its minimum ] (within a quiet breath).
At the end of expiration, the inward elastic force of the lungs is 3 [ A at its minimum / B increasing from its minimum to its maximum / C at its maximum / D decreasing from its maximum to its minimum ] (within a quiet breath).
At the end of expiration, 4 [ A gas (air) flows in / B there is no gas flow / C gas flows out ].
At the end of expiration, the pressure inside the lungs (alveolar pressure) is 5 [ A negative compared / B equal / C positive compared ] to the atmospheric pressure.
At the end of expiration, the negative pleural pressure is 6 [ A at its minimum / B increasing from its minimum to its maximum / C at its maximum / D decreasing from its maximum to its minimum ] (within a quiet breath).
Answer
1 [ B relaxing ]
2 [ A at its minimum ]
3 [ A at its minimum ]
4 [ B there is no gas flow ]
5 [ B equal ]
6 [ A at its minimum ]
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