Trachea are generally highly elastic but they may calcify with age. The trachealis muscle connects the ends of the incomplete rings and contracts during coughing, reducing the size of the lumen of the trachea to increase the rate of air flow. The esophagus lies posteriorly to the trachea, adjoining along the tracheoesophageal stripe. Circular horizontal bands of fibrous tissue called the annular ligaments of trachea join the tracheal rings together. The cartilaginous rings are incomplete to allow the trachea to collapse slightly so that food can pass down the esophagus. A flap-like epiglottis closes the opening to the larynx during swallowing
What Is Life During the verses, Gordon moves to a square, Motown-style beat – or "rock-steady Northern soul backbeat" in Leng's words – before returning to the "galloping rhythm" of the more open, "knockout" choruses, and the song is driven equally by Badfinger drummer Mike Gibbins' powerful tambourine work. On "What Is Life", Spector provided what music critic David Fricke terms "echo-drenched theater", in the form of reverb-heavy brass, soaring strings (arranged by John Barham) and "a choir of multitracked Harrisons". The vocals and Barham's contribution, along with a brief slide-guitar commentary from Harrison over the final verse, were overdubbed at Trident Studios,