All are true regarding trachea EXCEPT?: (A) Has C shaped cailages, (B) Outer diameter is 2 cm, (C) More than 20 hyaline cailages, (D) Isthmus of thyroid gland lies at 2, 3 and 4th tracheal rings
Answer is C. Trachea Length - 10- 15cm Diameter - 2cm (males), 1.5cm (females) Upper end - at lower end of cricoid cailage. Lower end - sternal angle C6 - T6 (erect position in living person). Fibroelastic wall. Cailaginous skeleton suppoed by 16 - 20 C- Shaped rings. Lumen lined by ciliated pseudostratified columnar epithelium