Lab2-Human Skeleton Below Skull

Overview

This lecture covers key bones of the human skeleton below the skull, including the hyoid, sternum, and ribs, along with their structure and terminology.

The Hyoid Bone

• The hyoid bone is located beneath the jaw.
• It resembles a small horseshoe or jaw with "fangs."
• The hyoid is not directly attached to other bones and supports tongue movement.

The Sternum

• The sternum, or breastbone, runs down the center of the chest.
• The sternum consists of three parts: the manubrium (upper), the body (middle), and the xiphoid process (lower).
• Visible separations distinguish the parts of the sternum.

The Costal Cartilage

• Costal cartilage connects the ribs to the sternum.
• This cartilage provides flexibility and allows the rib cage to expand.
• "Costal" refers to the ribs.

The Ribs

• Ribs are flat bones forming the rib cage.
• They protect vital organs such as the heart and lungs.
• Each rib is connected to the sternum via costal cartilage.

Key Terms & Definitions

• Hyoid bone — a U-shaped bone beneath the jaw, supporting tongue muscles.
• Sternum — the flat bone at the center of the chest, composed of manubrium, body, and xiphoid process.
• Manubrium — the upper part of the sternum.
• Xiphoid process — the small, lower tip of the sternum.
• Costal cartilage — cartilage connecting ribs to the sternum.
• Rib — flat bone forming the sides of the rib cage.

Action Items / Next Steps

• Review the structure and functions of the hyoid bone, sternum, ribs, and costal cartilage.
• Memorize the three parts of the sternum and their names.