Yolanda is asked to review a bone slide that her professor has set up under the microscope. She sees concentric layers surrounding a central cavity. Is this bone section taken from the diaphysis or the epiphyseal plate of the specimen?

Verified step by step guidance

1. Identify the key features observed in the bone slide: concentric layers surrounding a central cavity.
2. Recall the structure of a long bone, which includes the diaphysis (shaft) and the epiphyses (ends).
3. Understand that the diaphysis of a long bone contains the medullary cavity surrounded by compact bone, which is organized into concentric layers called osteons or Haversian systems.
4. Recognize that the epiphyseal plate, also known as the growth plate, is a region of cartilage found in growing bones and does not have concentric layers surrounding a central cavity.
5. Conclude that the presence of concentric layers surrounding a central cavity indicates that the bone section is taken from the diaphysis, not the epiphyseal plate.

Key Concepts

Bone Structure

Bone is composed of a dense matrix that includes concentric layers called lamellae, which surround a central cavity known as the Haversian canal. This structure is crucial for understanding how bones are organized and how they function in supporting the body and facilitating movement.

Diaphysis vs. Epiphyseal Plate

The diaphysis is the long, tubular shaft of a long bone, primarily composed of compact bone, while the epiphyseal plate, or growth plate, is a hyaline cartilage structure found at the ends of long bones. The presence of concentric layers suggests that the slide is likely from the diaphysis, as the epiphyseal plate does not exhibit this layered structure.

Microscopic Anatomy of Bone

The microscopic anatomy of bone includes various structures such as osteons, which are the functional units of compact bone. Each osteon consists of concentric lamellae surrounding a central canal, which is essential for nutrient and waste exchange. Recognizing these features helps in identifying the specific type of bone tissue being observed.