Trachea into left and right main bronchi. The trachea begins level with the sixth cervical vertebra and the carina is found at the level of the fifth thoracic vertebra (T5), opposite the sternal angle and can be positioned up to two vertebrae lower or higher, depending on breathing. The trachea is surrounded by rings of hyaline cartilage; these rings are incomplete and C-shaped. The cricoid cartilage is attached to the first tracheal ring at top of the trachea and acts as the bottom of the larynx. There are fifteen to twenty rings in total, separated by narrow intervals. These reinforce the
Given name by the parents at birth. In informal situations, given names are often used in a familiar and friendly manner. In more formal situations, a person's surname is more commonly used—unless a distinction needs to be made between people with the same surname. The idioms "on a first-name basis" and "being on first-name terms" refer to the familiarity inherent in addressing someone by their given name. By contrast, a surname (also known as a family name, last name, or "gentile" name), which is normally inherited, is typically shared with other members of one's immediate family. Regnal names and religious or monastic