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.
List of Birth Control Pill Brands. Birth control pills come in different brands and strengths. Photo Credit Dynamic Graphics Group/Dynamic Graphics Group/Getty Images. Birth control pills are a popular way for women to prevent an unwanted pregnancy.All types of birth control pills contain synthetic forms of the hormones estrogen and progesterone, though some pills may only contain one type of hormone.The hormones prevent pregnancy by suppressing ovulation and alter the uterine walls so the egg cannot implant.When taken every day at the same time, birth control pills are almost 100 percent effective in preventing pregnancy. Many different brands of birth control are on the market.he hormones prevent pregnancy by suppressing ovulation and alter the uterine walls so the egg cannot implant. When taken every day at the same time, birth control pills are almost 100 percent effective in preventing pregnancy. Many different brands of birth control are on the market.