Skeletal System Overview

Overview

This lecture introduces and reviews key bones and features of the human skeletal system, focusing on anatomy terminology relevant for the KIN 170 Lab Midterm.

Major Long Bone Structures

• The diaphysis is the shaft or central part of a long bone.
• The medullary cavity is a hollow area inside the diaphysis that contains bone marrow.

Skull Bones and Features

• The frontal bone forms the forehead and part of the eye socket.
• The parietal bone is located on the upper sides of the skull.
• The occipital bone forms the back and base of the skull.
• The temporal bone is found on the sides and base of the skull.
• The ethmoid bone is a delicate bone in the front of the cranium, between the eyes.
• The cribriform plate is a part of the ethmoid bone with small holes for olfactory nerves.
• The crista galli is a vertical projection of the ethmoid bone.
• The perpendicular plate is a thin plate of bone forming part of the nasal septum.
• The sagittal suture is the joint between the two parietal bones.
• The occipital condyles are rounded projections that articulate with the first cervical vertebra.
• The foramen magnum is a large opening at the base of the skull for the spinal cord.
• The mastoid process is a bony prominence behind the ear on the temporal bone.
• The anterior cranial fossa is the front depression in the floor of the cranial base.

Key Terms & Definitions

• Diaphysis — Shaft of a long bone.
• Medullary Cavity — Central cavity of bone shafts where marrow is stored.
• Frontal Bone — Forehead portion of the skull.
• Parietal Bone — Side and roof bone of the skull.
• Occipital Bone — Posterior and base part of the skull.
• Temporal Bone — Sides and base of the skull.
• Ethmoid Bone — Bone between the nasal cavity and orbits.
• Cribriform Plate — Perforated ethmoid bone structure for olfactory nerves.
• Crista Galli — Upward projection of the ethmoid bone.
• Perpendicular Plate — Thin bone forming part of the nasal septum.
• Sagittal Suture — Joint uniting two parietal bones.
• Occipital Condyles — Articulate skull with the spine.
• Foramen Magnum — Opening for the spinal cord in the skull.
• Mastoid Process — Protrusion behind the ear on the temporal bone.
• Anterior Cranial Fossa — Frontal depression in the base of the skull.

Action Items / Next Steps

• Review labeled diagrams of the major skull bones and long bone structures.
• Memorize the key terms and definitions for all bones and features listed.
• Prepare for midterm identification questions using practice flashcards.