Spongy bone tissue does not contain osteons that constitute compact bone tissue. Instead, it consists of trabeculae, which are lamellae that are arranged as rods or plates. Red bone marrow is found between the trabuculae. Blood vessels within this tissue deliver nutrients to osteocytes and remove waste.
Where is lamellae bone found?
The lamellae are concentrically located around a central canal (haversian canal) which contained blood vessels, nerves, and loose connective tissue. Volkmann’s canals may be seen connecting haversian canals.
What are lamellae and osteons?
osteon, the chief structural unit of compact (cortical) bone, consisting of concentric bone layers called lamellae, which surround a long hollow passageway, the Haversian canal (named for Clopton Havers, a 17th-century English physician).
How is bone lamellae formed?
Lamellar bone is usually formed in apposition to an existing surface. For the formation of lamellar bone, osteoblasts assume a distinct three-dimensional orientation in coordination with neighbor osteoblasts, and they form a continuous layer of bone in a unidirectional way.
Is lamellar bone compact bone?
Compact bone consists of closely packed osteons or haversian systems. The osteon consists of a central canal called the osteonic (haversian) canal, which is surrounded by concentric rings (lamellae) of matrix. Between the rings of matrix, the bone cells (osteocytes) are located in spaces called lacunae.
When does woven bone become lamellar bone?
three years
Woven bone has a matrix of interwoven coarse collagen fibers with osteocytes distributed at random. It is less organized than lamellar bone. Woven bone is replaced by lamellar bone at age two or three years. Lamellar bone is a mature bone that results from the remodeling of immature woven bone.
Is lamellar bone mature?
Woven bone is replaced by lamellar bone at age two or three years. Lamellar bone is a mature bone that results from the remodeling of immature woven bone. Lamellar bone is highly organized; stress-oriented collagen of lamellar bone gives its anisotropic properties.
What does the periosteum do?
The periosteum is a complex structure composed of an outer fibrous layer that lends structural integrity and an inner cambium layer that possesses osteogenic potential. During growth and development it contributes to bone elongation and modeling, and when the bone is injured, participates in its recovery.
Does spongy bone have lamellae?
The spongy bone tissue does not contain osteons. It consists of layers of bone matrix (= lamellae M) arranged in an irregular latticework of thin plates of bone called trabeculae. The spaces within the trabeculae are filled with red bone marrow and blood vessels.
Are osteons avascular?
In contrast to pigeon humeri where laminar bone is present, the primary tissue of these bat bones is largely avascular, but secondary osteons are present and are usually in the deeper cortex.
What is the purpose of yellow marrow?
Yellow bone marrow contains mesenchymal stem cells (marrow stromal cells), which produce cartilage, fat and bone. Yellow bone marrow also aids in the storage of fats in cells called adipocytes. This helps maintain the right environment and provides the sustenance that bones need to function.
