External intercostals contract to elevate the ribs during inhalation while internal intercostals contract to depress the ribs during forced exhalation.
While inhalation is simply the act of breathing in, exhalation is the exact opposite, breathing out.
The intercostal muscles are muscles situated in between the ribs of an animal or a person. It is separated into:
To learn more about muscles, see: https://brainly.com/question/9883108?referrer=searchResults
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