Bone

Question 1

functions of the skeleton

Answer 1

support
protection
movement
production of blood cells
storage of minerals
endocrine regulation

Question 2

types of bone

Answer 2

long bone e.g. femur
sesamoid bones (embedded in tendons) e.g. putella
flat bone e.g. cranium
short bone e.g. wrist joint
irregular bone e.g. bones of the pelvis

Question 3

types of bone composition

Answer 3

bones made of osseous tissue
spongy bone- light and strong
compact bone- protective layer

Question 4

structure of long bones

Answer 4

longer than wide
composed mostly of compact bone
shaft of bone called diaphysis
two ends of bone called epiphysis
medullary canal (inside diaphysis) where bone marrow is found

Question 5

types of bone cells and their function

Answer 5

osteoblasts- create (growth and repair)
osteoclasts- break down (remodelling)
osteocytes- monitor (communicate response to stresses)

Question 6

describe the microstructure of compact bone

Answer 6

made up of parallel tubes called osteons
each osteon made up of a central cannel surrounded by a series of expanding rings
central cannel contain blood vessels and connect to other channels through perforations

Question 7

describe the microstructure of spongy bone

Answer 7

resembles honeycomb
contains osteocytes within lacuni but they are not arranges in concentric circles
spaces contain red bone marrow

Question 8

describe the process of osteogenesis

Answer 8

begins at ossification centre and starts with cartilage
development of bony collar (8 weeks gestation)
blood supply develops and bone starts to replace cartilage
bone lengthening occurs at growth plate, producing cartilage which is then converted into bone
over time the whole growth plate is converted to bone

Question 9

bone remodelling

Answer 9

around 10% bone replaced each year
bones subjected to higher stress are remodelled faster
bone density changes in response to the forces placed on a bone- Wolff’s law