Inhalation or inspiration? During inhalation, motor impulses from the medulla travel along the phrenic nerves to the diaphragm, which contracts and moves down. Impulses are sent along the intercostal nerves to the external intercostal muscles, which pull ribs up and out.? The chest cavity is expanded and expands the parietal pleura. The visceral pleura adheres to the parietal pleura and is also expanded, and in turn expands the lungs. Intrapulmonic pressure decreases and air rushes into the lungs. ??注釋：? ??inhalation? /??nh??le???n/ 吸氣；吸入 ??inspiration /??nsp??re???n/ 吸氣；吸入 ??motor impulse /?m??t? ??mp?ls/ 運(yùn)動沖動 ??medulla? /m??d?l?; m??d?l?/? (也稱medulla oblongata /??bl???ɡɑ?t?/) 延髓 ??phrenic nerve /?fr?n?k ?n??v/ 膈神經(jīng) ??diaphragm /?da??fr?m/ 膈；膈膜；橫膈膜 ??contract? /k?n?tr?kt/ 收縮 ??impulse? /??mp?ls/ 沖動；脈沖 ??intercostal nerve /??nt??k?st(?)l ?n??v/ 肋間神經(jīng) ??external intercostal muscle /?k?st??n(?)l ??nt??k?st(?)l ?m?s(?)l/ 肋間外肌 ??rib /r?b/ 肋骨 ??chest cavity /t??st ?k?v?t?/ 胸腔 ??expand /?k?sp?nd/ 擴(kuò)大；擴(kuò)張；擴(kuò)充；擴(kuò)展? ??parietal pleura /p??ra??t(?)l ?pl?(?)r?/ 壁胸膜；胸膜壁層 →pleura的復(fù)數(shù)形式為pleurae /?pl?(?)ri?/ ??visceral pleura /?v?s?r?l ?pl?(?)r?/ 臟胸膜；臟層胸膜 →pleura的復(fù)數(shù)形式為pleurae /?pl?(?)ri?/ ??adhere /?d?h??/ 黏附；附著 (通常用作adhere to) ??in turn 轉(zhuǎn)而；相應(yīng)地 ??lung? /l??/ 肺