1.3 Bone and the Skeleton

Question 1

What is bone?

Answer 1

A type of connective tissue made up of cells suspended in a matrix.

Question 2

What are bones?

Answer 2

Organs made up of bone tissue with cortical bone (compact) on the outside, trabecular bone (spongy) on the inside, and a central medullary cavity.

Question 3

Where is cortical bone found?

Answer 3

The outside of a bone.

Question 4

Where is trabecular bone found?

Answer 4

The inside of a bone.

Question 5

What are three types of bone?

Answer 5

Long, flat, short

Question 6

Describe a flat bone.

Answer 6

no medullary cavity, two layers of compact bone surroundin gspongy bone and air space.

Question 7

Describe a short bone

Answer 7

no medullary cavity, develops from a single centre of ossification.

Question 8

What is the PERIOSTEUM?

Answer 8

covers the outside of a bone in two layers, contains sensory nerves and blood/lymphatic vessels.

Question 9

Does more osteogenesis or osteolysis occur in periosteum?

Answer 9

Osteogenesis.

Question 10

What is the ENDOSTEUM?

Answer 10

Lines the medullary cavity in a single layer.

Question 11

Does more osteogenesis or osteolysis occur in endosteum?

Answer 11

Osteolysis.

Question 12

How do arteries enter bones?

Answer 12

Arteries enter via nutrient foramen in diaphysis.

Question 13

How is calcified cartilage supplied with blood?

Answer 13

Blood vessels pass through subchondral bone to supply calcified cartilage.

Question 14

How is cortical bone supplied with blood?

Answer 14

Haversian and Volkmann canals.

Question 15

How is trabecular bone supplied with blood?

Answer 15

Via bone marrow.

Question 16

What are osteons?

Answer 16

Circles of bone marrow with a central canal, important structurally.

Question 17

What do sesamoid bones do? (3)

Answer 17

Ease tendon pathway, prevent excessive tendon wear, increase movement arm of muscle.

Question 18

What do surface markings do? (3)

Answer 18

provide leverage
respond to strain within bones
articulation with other bones

Question 19

What do osteoblasts do?

Answer 19

Bone formation

Question 20

What do osteoclasts do?

Answer 20

Bone resorption

Question 21

What do osteocytes do?

Answer 21

Support/maintain bone structure

Question 22

Where do osteoblasts originate?

Answer 22

Mesenchymal cells in bone marrow.

Question 23

Where do osteocytes originate?

Answer 23

Mesenchymal cells in bone marrow.

Question 24

Where do osteoclasts originate?

Answer 24

Hematopoitic cells in bone marrow.

Question 25

where are osteoblasts found?

Answer 25

Surfaces of trabecules

Question 26

where are osteoclasts found?

Answer 26

Surfaces of trabecules

Question 27

where are osteocytes found?

Answer 27

Inside the bone