Quick Answer. The function of the cartilaginous rings of the trachea is to stabilize the trachea and keep it rigid while allowing the trachea to expand and lengthen when the person breathes. If the trachea was not supported in this way, it would simply collapse because of the pressure of the chest.
1 The Pill. The pill is the common name for oral contraception. It's one of the safest, most effective, and popular methods of birth control. The pill is made up of synthetic forms of hormones that naturally occur in a female's body - progestin and estrogen.
Pill Remains Most Common Birth Control Method. THURSDAY, Dec. 11, 2014 (HealthDay News) -- The pill remains one of the most popular methods of birth control for women, along with female sterilization and condoms, a new report shows. Among the two-thirds of women aged 15 to 44 who used birth control between 2011 and 2013, approximately 16 percent used the pill.