Plate 17 - Long Bone Structure

Question 1

Epiphysis

Answer 1

End of bone. When mature, it is largely cancellous bone. Articulating surfaces is lined with 3-5mm of hyaline (articular) cartilage.

Question 2

Diaphysis

Answer 2

Shaft of long bone. Has a marrow-filled medullary cavity surrounded by compact bone lined externally by bone cell-forming periosteum and internally by bone-forming endosteum.

Question 3

Articular Cartilage

Answer 3

Smooth, slippery, porous, malleable, insensitive, and bloodless. Only remaining evidence of an adult bone’s cartilaginous past. Is the articulating surface in freely movable joints.

Question 4

Periosteum

Answer 4

Fibrous, cellular, vascular, and highly sensitive life support sheath for bone, providing a source of bone cells throughout life.

Question 5

Cancellous (spongy) Bone

Answer 5

Made of interwoven beams (trabeculae) of bone in epiphyses of long bones, bodies of vertebrae, and other bones without cavities. Spaces among the trabeculae are filled with red or yellow bone marrow and blood vessels. Forms a dynamic latticed truss capable of mechanical alteration in response to stresses of weight, postural change, and muscle tension.

Question 6

Compact Bone

Answer 6

Forms stout walls of the diaphysis and thinner outer surface of other bones where there is no articular cartilage.

Question 7

Medually cavitiy

Answer 7

Cavity of diaphysis. Contains marrow: red in young, turns to yellow in maturity. Lined by endosteum.

Question 8

Red Marrow

Answer 8

Red, gelatinous substance made of RBC/WBC in variety of developmental forms (hematopoietic tissue) and specialized capillaries (sinusoids) enmeshed in reticular tissue. In adults, it is limited to sternum, vertebrae, ribs, hip bones, clavicles, long bones, and cranial bones.

Question 9

Yellow Marrow

Answer 9

Fatty connective tissue that does not produce blood cells.

Question 10

Nutrient Artery

Answer 10

Principal artery and major supplier of oxygen and nutrients to shaft or body of bone.

Question 11

Branches

Answer 11

Part of nutrient artery. Snake through labyrinthine canals of haversian systems and other tubular cavities of bones.