EMBRYOLOGY
RESPIRATORY SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Down and In
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Up & In
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Up & Out
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Just up
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Detailed explanation-1: -When the lungs inhale, the diaphragm contracts and pulls downward. At the same time, the muscles between the ribs contract and pull upward. This increases the size of the thoracic cavity and decreases the pressure inside. As a result, air rushes in and fills the lungs.
Detailed explanation-2: -During inhalation, the ribs move up and outward and the diaphragm moves in. this movement decrease the space in our chest cavity and the air rushes in. During exhalation, the ribs moves down and inward and the diaphragm moves up. This movement increases the space in our chest cavity and the air is pushed out.
Detailed explanation-3: -The movement of the rib cage is controlled by the intercostal muscles, and the diaphragm is a skeletal muscle. During inspiration the diaphragm and the external intercostal muscles contract, causing an increase in the thoracic cavity volume.