Microscopic Structure of Bone Overview

Questions and Answers

What is spongy bone?

Made up of trabeculae, it is found in flat, short, irregular, and sesamoid bones, and is located at the epiphyses of long bones, closely associated with red bone marrow.

What is compact bone?

A type of bone tissue that has very few spaces and coats the exterior of all bones; it makes up the majority of the diaphysis of long bones.

What are trabeculae?

The flat plates of bone found in spongy bone that form the spaces where red bone marrow is located.

What is an osteon?

The functional unit of compact bone, also known as a Haversian system, containing concentric lamellae, lacunae, canaliculi, central canals, and perforating canals. Signup and view all the answers

What is the central canal?

The central portion of an osteon that provides a space for blood vessels, nerves, and lymphatic vessels. Signup and view all the answers

What are concentric lamellae?

Layers of bone matrix arranged in concentric circles within an osteon. Signup and view all the answers

What is bone matrix?

The solid material composed of inorganic salts such as calcium and phosphorus that makes up most of compact bone tissue. Signup and view all the answers

What are lacunae?

Spaces found in the bone matrix where osteocytes can be found. Signup and view all the answers

What are osteocytes?

Mature bone cells responsible for the daily metabolism of bone. Signup and view all the answers

What are canaliculi?

Tiny canals that radiate from the lacunae, allowing for the transportation of nutrients and waste to/from osteocytes. Signup and view all the answers

What are perforating canals?

Also known as Volkmann's canals, these are tunnels that penetrate transversely into an osteon, allowing vessel travel throughout compact bone. Signup and view all the answers

What are osteogenic cells?

The only bone cells capable of dividing to create new bone cells, assisting with bone growth. Signup and view all the answers

What are osteoblasts?

Bone-building cells that secrete bone matrix and remove calcium from the blood to make bone matrix. Signup and view all the answers

What are osteoclasts?

Cells that break down bone matrix through resorption and release calcium back into the bloodstream. Signup and view all the answers

Study Notes

Microscopic Structure of Bone

Spongy Bone: Composed of trabeculae, primarily found in flat, short, irregular, and sesamoid bones; located at the epiphyses of long bones. Associated with red bone marrow.
Compact Bone: Dense bone tissue with minimal spacing, covering all bones' exterior. Major component of the diaphysis in long bones.
Trabeculae: Flat plates of bone forming the structure of spongy bone, creating spaces for red bone marrow.
Osteon (Haversian System): Functional unit of compact bone consisting of concentric lamellae, lacunae, canaliculi, central canals, and perforating canals.
Central Canal: Central part of an osteon that houses blood vessels, nerves, and lymphatic vessels within compact bone.
Concentric Lamellae: Layers of bone matrix arranged concentrically within an osteon, contributing to its structural integrity.
Bone Matrix: Solid substance composed of inorganic salts like calcium and phosphorus, making up the majority of compact bone tissue.
Lacunae: Small spaces within the bone matrix that contain osteocytes, the mature bone cells.
Osteocytes: Mature bone cells responsible for bone's daily metabolic functions, situated in lacunae.
Canaliculi: Tiny canals extending from lacunae that facilitate the transport of nutrients, oxygen, and waste between osteocytes and blood supply.
Perforating Canals (Volkmann's Canals): Tunnels that cross osteons transversely, accommodating blood vessels, nerves, and lymphatic vessels in compact bone.
Osteogenic Cells: Unique bone cells capable of division and production of new bone cells, crucial for bone growth; located deep in the periosteum, endosteum, and central canals.
Osteoblasts: Bone-forming cells that secrete bone matrix by utilizing calcium from the bloodstream; found deeper in the periosteum and endosteum.
Osteoclasts: Cells responsible for bone resorption, breaking down bone matrix to release stored calcium into the bloodstream. Modified white blood cells located in the endosteum.

Description

This quiz focuses on the microscopic structure of bone, specifically the characteristics of spongy and compact bone. Explore key definitions and features that differentiate these two types of bone tissue in the skeletal system.