Basic Osteology

Question 1

What are the 5 types of bones?

Answer 1

Long bones
Short bones
Flat bones
Irregular bones
Sesamoid bomes

Question 2

Woven bone

Answer 2

Fragile bone found in stages of bone formation and repair

Question 3

Lamellar bone

Answer 3

Compact or cortical bone which covers spongy bone and shafts of long bones
- protects and supports

Cancellous and spongy bone which forms at end of long bones and the inner mass of others
- provides support and stores RBM

Question 4

Adult long bone

Answer 4

Question 5

What are Ostend also known as?

Answer 5

Harversian systems

Question 6

What does a compact bone consist of

Answer 6

Structural units called harversian systems/ osteomyelitis arranged in a regular fashion

Question 7

Cancellous bone

Answer 7

Bone that is unorganised extensions of bone tissue around bone marrow spaces

Question 8

Cross section through osteon

Answer 8

Question 9

what material makes up the bone

Answer 9

osseous tissue

Question 10

the composition of osseous tissue

Answer 10

widely separated cells surrounded by large amounts of intercellular substance

Question 11

osteoid

Answer 11

organic material that forms bone matrix and gives bone tensile strength

Question 12

what does osteoid consist of

Answer 12

ground substance of proteoglycans and protein scaffold of TYPE I collagen scaffold

Question 13

what gives bone its strength and hardness without being brittle

Answer 13

crystals of inorganic mineral salts that attach themselves to OSTEOID
collagen fibres

Question 14

what are the mineral salts that give the bone its strength called

Answer 14

CALCIUM HYDROXYAPETITE

Question 15

osteoprogenitor cells

Answer 15

stem cells of bone

Question 16

where are osteoprogenitor cells found

Answer 16

inner lining of periosteum and endosteum

Question 17

osteoblasts

Answer 17

secretory cells found on surface of bone matrix - bone producing cells

Question 18

what do osteoblasts do?

Answer 18

secrete bone matrix and alkaline phosphatase which calcifies matrix = makes bone

Question 19

osteocytes

Answer 19

mature osteoblasts trapped in lacunae between layers of lamellae in cortical bone and have function in daily metabolism of bone tissue

Question 20

bone resorption cells

Answer 20

osteoclasts

Question 21

what does osteoclasts contain

Answer 21

many lysosomes and secrete substances which break down bone matrix + phagocytose the remains

Question 22

what do long bones begin as

Answer 22

cartilage

Question 23

ossification

Answer 23

process of bone formation

Question 24

how does cartilage turn into bone

Answer 24

centre ossifies, then the eds leaving a strip of specialised growing cartilage in between

Question 25

primary ossification centre

Answer 25

first place where bone formation begins in axle of long bone or irregular bone

Question 26

secondary ossification centre

Answer 26

area of ossification that appears after primary ossification of edges of bones - appear at different times of child’s development

Question 27

what does the diaphysis shaft contain

Answer 27

• MEDULLARY CAVITY
• contains the bone marrow

Question 28

what is the medullary cavity lined with

Answer 28

thin membrane called the end osteum
- this is the site for osteoblasts and osteoclasts

Question 29

what is the epiphyseal growth plate

Answer 29

plate of hyaline cartilage that separates epiphysis from rest of the bone
- growth of bone occurs at this point

Question 30

where does ossification occur

Answer 30

metaphysis

Question 31

what is the process ossification

Answer 31

the process by which bones form in the body

Question 32

what is the human embryo composed of

Answer 32

fibrous membranes and hyaline cartilage

Question 33

when does ossification begin

Answer 33

6th or 7th month

Question 34

two types of ossification

Answer 34

• intramembranous ossification
• endochondral ossification

Question 35

intramembranous ossification
where does it occur and form

Answer 35

• occurs in membranes
• forms cancellous bone
• forms flat skull bones and clavicles

Question 36

endochondral ossification

Answer 36

• occurs in rods of cartilage
• forms long bones

Question 37

steps of endochondral ossification

Answer 37

1. cartilage template surrounded by perichondrium
2. bony collar forms
3. primary ossification centre forms
4. blood vessels enter
5. marrow cavity forms
6. thickening and lengthening of collar forming diaphysis
7. formation of secondary ossification centres forming epiphysis
8. remains of cartilage
9. epiphyseal closure

Question 38

4 main factors that affect growth of bone

Answer 38

• nutritional factors
• biochemical factors
• hormones
• blood supply

Question 39

4 steps of bone repair

Answer 39

1. fracture hematoma formation
2. fibrocartilaginous callus formation
3. formation of bony callus
4. bone remodelling