Bone

Question 1

In a long bone, where would you find the diaphysis, epiphysis and metaphysis?

Answer 1

Epiphysis = the ends.
Diaphysis = the long middle part.
Metaphysis = between the diaphysis and epiphyses. Area of growth in the developing bone.

Question 2

What is the name of the tough fibrous covering around the outside of the bone? And which parts of the bone are NOT covered by this?

Answer 2

Periosteum covers the whole bone EXCEPT the ends, which are covered by hyaline articular cartilage.

Question 3

How does the bone structure differ between the cortex and the medullary cavity?

Answer 3

Cortex = compact, cortical bone.

Medullary cavity = trabeculae, cancellous bone

Question 4

What are the two types of marrow?

Answer 4

Yellow marrow = adipose; never broken down, even under starvation conditions.
Red marrow = haematopoietic.
NOTE that not all long bones have red marrow.

Question 5

Definition: repeated small pressures that accumulate to eventually cause a break.

Answer 5

Answer: FATIGUE

Question 6

Definition: sudden trauma causes an immediate break.

Answer 6

Answer: MONOTONIC FAILURE

Question 7

List THREE functions of bones.

Answer 7

Any of the following (different bones have various properties depending on location/function):

• Resist tension, compression, torsion, shear
• Articulations - joint surfaces; muscle action
• Tendon, ligament and joint attachment
• Fatigue life and monotonic strength
• Protective space for other organs (e.g. skull, ribs)
• Air filter and transfer surface (nasal turbinates)
• Transmit vibration (malleus, incus, stapes)

Question 8

What are the TWO ways that bones are involved in the body’s metabolism?

Answer 8

• Haematopoiesis (production of blood cells)

- Calcium store