Bone Structure I

Question 1

6 Functions of the Skeleton

Answer 1

support, protection, movement, mineral storage/homeostasis, blood cell production, lipid storage

Question 2

function of the skeleton - support - 2 points

Answer 2

framework to support soft tissue, point of attachment of muscles

Question 3

function of the skeleton - protection - 1 point

Answer 3

to protect internal organs

Question 4

function of the skeleton - movement - 2 points

Answer 4

bones = levers which muscles are attached, muscles contract to allow movement

Question 5

function of the skeleton - mineral storage/homeostasis - 2 points

Answer 5

calcium/phosphorus, distributed on demand to maintain mineral balance

Question 6

function of the skeleton - blood cell production - 2 points

Answer 6

Red marrow in certain bones produce RBCs, some WBCs and platelets

Question 7

function of the skeleton - lipid storage - 1 point

Answer 7

yellow bone marrow serves as chemical energy reserve

Question 8

2 types of connective tissue

Answer 8

cartilage and bone (the proportions of these 2 change as you grow)

Question 9

Differences between cartilage and bone - 3 points

Answer 9

cartilage = tough/flexible/relatively light, bone = rigid/heavier/more resistant to deforming forces

Question 10

Diaphysis

Answer 10

shaft of the bone

Question 11

Epiphysis - 3 points

Answer 11

extremities of the bone, covered in articular cartilage, thin layer of hyaline cartilage where bone forms a joint with another bone

Question 12

Metaphysis

Answer 12

where the diaphysis and the epiphysis meet

Question 13

Epiphyseal Plate

Answer 13

only found in growing bone, where the metaphysis includes a layer of hyaline cartilage, where bone growth occurs

Question 14

Epiphyseal Line

Answer 14

in adult bone, the hyaline cartilage at the metaphysis is replaced by bone

Question 15

Medullary Cavity - 3 points

Answer 15

lies within diaphysis, lined with thin membrane = endosteum, contains fatty yellow bone marrow in adults

Question 16

Periosteum - 2 points

Answer 16

tough sheath of dense irregular connective tissue, covers surface of bone not covered by articular cartilage

Question 17

Role of Periosteum - 4 points

Answer 17

contains bone forming cells which enable bone growth in diameter (not length), protects the bone & assists in fracture repair, nourishes the bone tissue, serves as a point of attachment for muscles and tendons

Question 18

Bone tissue

Answer 18

made up of matrix of extracellular material which surrounds widely separated cells

Question 19

Matrix contains … 3 points

Answer 19

mineral salts (mainly Calcium Phosphate & some Calcium Carbonate), framework formed by collagen fibres, water

Question 20

Ossification/Calcification

Answer 20

Salts are deposited in framework, they crystallise and the tissue hardens - initiated by osteoblasts

Question 21

4 types of bone cell

Answer 21

Osteogenic cells, osteoblasts, osteocytes, osteoclasts

Question 22

Osteogenic Cells - 2 points

Answer 22

found within periosteum, endosteum & canals within bone carrying blood vessels, cell division creates daughter cells which develop into osteoblasts

Question 23

Osteoblasts - 4 points

Answer 23

bone-building cells, synthesise and secrete collagen & other components required to build matrix, initiate ossification, as osteoblasts secrete the matrix they become trapped - become osteocytes

Question 24

Osteocytes - 3 points

Answer 24

mature osteoblasts which no longer produce new bone tissue, have long branching arms that connect them to neighbouring osteocytes - facilitates communication between them and metabolism of bone tissue by exchange of nutrients/waste with blood

Question 25

Osteoclasts - 4 points

Answer 25

huge cells, mainly found in endosteum, derived from fusion of up to 50 monocytes (a type of WBC), where they face the bone surface their plasma membrane is folded to forma ruffled border, here powerful enzymes and acids breakdown underlying bone matrix - reabsorption (normal part of bone development/growth/maintenance/repair

Question 26

Spaces in Bone act as ...

Answer 26

storage areas - for red bone marrow, channels - for blood vessels supplying bone with nutrients

Question 27

whether a bone is compact or cancellous depends on ...

Answer 27

size and distribution of spaces in the bone