Explain the process of breathing in humans, clearly differentiating between inhalation and exhalation.
Breathing in humans involves two main phases: inhalation and exhalation. During inhalation, the diaphragm contracts and moves downwards, while the rib cage moves upwards and outwards. This increases the volume of the chest cavity, creating a lower pressure inside. Air, being at higher atmospheric pressure, rushes into the lungs. During exhalation, the diaphragm relaxes and moves upwards, and the rib cage moves downwards and inwards. This decreases the volume of the chest cavity, increasing the pressure inside. Air is then forced out of the lungs.
Explanation
Key points: Description of diaphragm and rib cage movement for both inhalation and exhalation, change in chest cavity volume, and resultant air pressure differences.