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.
1 There are many different kinds of birth control pills (BCPs). 2  Many types of birth control pills contain two hormones: estrogen and progestin (which is similar to preogesterone). These are called combined birth control pills.  BCPs are also called âoral contraceptive pillsâ (OCPs), âhormone pills,â or âthe Pill.â.