For other uses, see Fiction (disambiguation). An illustration from Lewis Carroll's Alice's Adventures in Wonderland, depicting the fictional protagonist, Alice, playing a fantastical game of croquet. Fiction is a story or similar work derived from imaginationâin other words, not based strictly on history or fact.
In human physiology, the muscles of respiration are those muscles that contribute to inhalation and exhalation, by aiding in the expansion and contraction of the thoracic cavity.The diaphragm and, to a lesser extent, the intercostal muscles drive respiration during quiet breathing.Additional 'accessory muscles of respiration' are typically only used under conditions of high metabolic demand (e.g. exercise) or respiratory dysfunction (e.g. an asthma attack).dditional 'accessory muscles of respiration' are typically only used under conditions of high metabolic demand (e.g. exercise) or respiratory dysfunction (e.g. an asthma attack).
Breathing is an active process-requiring the contraction of skeletal muscles. The primary muscles of respiration include the external intercostal muscles (located between the ribs) and the diaphragm (a sheet of muscle located between the thoracic & abdominal cavities).ntra-alveolar pressure during inspiration & expiration. As the external intercostals & diaphragm contract, the lungs expand. The expansion of the lungs causes the pressure in the lungs (and alveoli) to become slightly negative relative to atmospheric pressure.