1. 1   These are formed by division of trachea.   Food descends from mouth to stomach through this muscular tube.   Larger dust particles in the inhaled air are trapped in the mucus and hair found here.   Exchange of gases occurs here.   Hint Half-n-half Clue   2. 2   It secretes saliva.   These are formed by division of trachea.   Exchange of gases occurs here.   Food is mixed with saliva here.   Half-n-half Clue   3. 7   Exchange of gases occurs here.   Food descends from mouth to stomach through this muscular tube.   Larger dust particles in the inhaled air are trapped in the mucus and hair found here.   It secretes saliva.   Half-n-half Clue   4. 6   Exchange of gases occurs here.   These are formed by division of trachea.   Food descends from mouth to stomach through this muscular tube.   It secretes saliva.   Half-n-half Clue   5. 8   It pumps blood to various parts of the body.   Larger dust particles in the inhaled air are trapped in the mucus and hair found here.   These are formed by division of trachea.   It is a muscular tube containing semicircular rings of cartilages.   Half-n-half Clue   6. 9   It secretes saliva.   It pumps blood to various parts of the body.   Food descends from mouth to stomach through this muscular tube.   Food is mixed with saliva here.   Half-n-half Clue   7. 3   It secretes saliva.   These are formed by division of trachea.   Food descends from mouth to stomach through this muscular tube.   Larger dust particles in the inhaled air are trapped in the mucus and hair found here.   Half-n-half Clue   FREE PREVIEW: Last 7 Questions not a part of the free preview. Get Premium Membership to view all questions.