9 - Bone Structure and the Skeletal system

Question 1

Ligament

Answer 1

Connects bone to bone

Question 2

tendon

Answer 2

Connects muscle to bone

Question 3

Cartilage

Answer 3

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together.

Question 4

Fibrocartilage

Answer 4

cartilage that contains fibrous bundles of collagen, such as that of the intervertebral disks in the spinal cord.

Question 5

bone

Answer 5

resists compression

Question 6

Synovium

Answer 6

membrane in joint that secretes lubricating fluid

Question 7

endochondral ossification

Answer 7

The formation of bone from pre-existing hyaline cartilage models. Forms long bones, blood vessels invade cartilage less. e.g. pelvis, shoulder

Question 8

intramembranous ossification

Answer 8

process by which bone forms directly from mesenchymal tissue. No cartilage, flat bones. cells proliferate and condense.

Question 9

What are the 7 functions of bone?

Answer 9

1) Support
2) Protection (brain)
3) Movement
4) Mineral and growth factor storage (calcium/phosphate)
5) Blood cell formation - hematopoiesis
6) Triglyceride (fat) storage
7) Hormone production - osteocalcin

Question 10

mechanical functions of bone

Answer 10

support, protect, levers

Question 11

metabolic functions of bone

Answer 11

calcium metabolism

bone marrow

Question 12

4 cell types in bone

Answer 12

osteogenic cells, osteoblasts, osteocytes, osteoclasts

Question 13

Osteoblasts

Answer 13

bone forming cells

• Synthesis bone matrix and prime for mineralisation
• plump cuboidal cells with organelles for synthesis
• form epithelioid layer on bone cell surface

Question 14

Osteocytes

Answer 14

a bone cell, formed when an osteoblast becomes embedded in the matrix it has secreted.
Maintaining mature cells inside
-engulfed in bone matrix during apposition so formed from osteoblasts.
- maintain junctions and cells sites for vascular supply
-involved in calcium homeostasis

Question 15

osteoclasts

Answer 15

large cells that resorb or break down bone matrix: Destroying cells

• large multi-nucleate cells used in reabsorption
• unique organelles and appearance

Question 16

lining cells

Answer 16

flattened osteoblasts that protect the bone and balance calcium levels

• osteoblasts fully completed synthesis and can be reactivated
• flat hard to see nucleus.

Question 17

bone matrix

Answer 17

rigid framework of bone that consists of tough protein fibers and mineral crystals
Collagen I, bone proteoglycan, some non-collagenous proteins (osteocalcin, osteonectin, osteopontin).
Hydroxyapatite mineral.

Question 18

Demineralised bone

Answer 18

removing the mineral component, making the bone bendy

Question 19

anorganic bone

Answer 19

removing collagen, making the bone brittle

Question 20

Types of bone tissue

Answer 20

compact and spongy

Question 21

compact bone

Answer 21

Hard, dense bone tissue that is beneath the outer membrane of a bone

Question 22

How are fractures repaired?

Answer 22

1) haematoma formation
2) soft callus formation- collagen laid down
3) Hard callus formation- hardening
4) bone remodelling

Question 23

cancellous (spongy) bone

Answer 23

contains little spaces like a sponge and is encased in the layers of compact bone

Question 24

bone remodelling

Answer 24

Process involving bone formation and destruction in response to hormonal and mechanical factors.