SKELETAL SYSTEM BONE TISSUE

Question 1

THE SKELETAL SYSTEM CONSISTS OF

Answer 1

-bones
-cartilages
-ligaments
-tendons

Question 2

OSTEOLOGY

Answer 2

study of bone structure and tx of bone disorders

Question 3

FUNCTIONS OF THE SKELETAL SYSTEM

Answer 3

1. support
2. protection
3. assistance in movement
4. mineral homeostasis
5. blood cell protection
6. triglyceride storage

Question 4

OSTEOID

Answer 4

new bone

Question 5

HEMATOPOIETIC TISSUE

Answer 5

tissue in which new blood cells are formed
-INFANTS: in medullary cavities of diaphysis and all areas of spongy bone
-ADULTS: between trabecular and spongy bones in flat bones, skull, sternum, ribs, hips, etc.

Question 6

CALCIFICATION

Answer 6

crystals form, combining with other ions and these mineral salts are deposited in a framework of collagen fibres - INITIATED BY OSTEOBLASTS

Question 7

HYDROXYAPATITE

Answer 7

calcium phosphate (most abundant) and calcium hydroxide

Question 8

COMPACT BONE

Answer 8

-80% of bones
-few spaces
-found beneath periosteum
-protection, support, resists compression

Question 9

SPONGY BONE

Answer 9

-20% of bones
-does not contain osteons
-located in interior of bone
-trabecular

Question 10

OSSIFICATION (OSTEOGENESIS)

Answer 10

1. initial bone formation
2. growth of bone during development
3. remodelling of bone
4. bone repair

Question 11

MESENCYME

Answer 11

loosely organized, mainly mesodermal embryonic tissue, develops into connective and skeletal tissues

Question 12

INTRAMEMBRANOUS OSSIFICATION

Answer 12

INITIAL BONE FORMATION
-week 8 of embryo development (flat bones like cranial, rib clavicle)
-bone forms directly within mesenchyme
-mesenchyme cells to cartilage to bone

Question 13

ENDOCHONDRAL OSSIFICATION

Answer 13

INITIAL BONE FORMATION
-2nd month of development (long bones like tibia, femur, humerous)
-forms from hyaline cartilage which develops from mesenchyme cartilage

Question 14

GROWTH IN LENGTH OF LONG BONE

Answer 14

1. INTERSTITIAL GROWTH OF CARTILAGE - on epiphyseal side of the epiphyseal plate
2. REPLACEMENT OF CARTILAGE - on diaphysial side through endochondral ossification

Question 15

FACTORS AFFECTING BONE GROWTH

Answer 15

1. minerals
2. vitamins
3. hormones

Question 16

COMMON FRACTURES

Answer 16

1. open (compound)
2. comminuted
3. greenstick
4. impacted
5. pott
6. colles

Question 17

DIAPHYSIS

Answer 17

LONG BONE STRUCTURE
-tube or shaft through long bone
-surrounds medullary cavity

Question 18

EPIPHYSES

Answer 18

LONG BONE STRUCTURE
-bone ends
-thin layer of hyaline cartilage covers joint surface

Question 19

PERIOSTEUM

Answer 19

LONG BONE STRUCTURE
-double layer membrane covering external surface of bone

Question 20

ENDOSTEUM

Answer 20

LONG BONE STRUCTURE
-internal bone covering

Question 21

OSTEOGENIC CELLS

Answer 21

-found in periosteum and endosteum
-in growing bones they are squamous cells and differentiate into osteoblasts

Question 22

OSTEOBLASTS

Answer 22

-bone forming cells

Question 23

OSTEOCYTES

Answer 23

-mature bone cells that occupy spaces (lacunae) that conform to their shape
-monitor and maintain bone matrix
-communicate info to cells about bone remodelling

Question 24

OSTEOCLASTS

Answer 24

-giant multinucleate cells located at sites of bone resorption
-increase SA for enzymatically degrading the bones and seal off area from surrounding matrix
-dissolve bone
-concentrated in endosteum

Question 25

EPIPHYSEAL PLATE

Answer 25

-also known as the metaphysis -between diaphysis and epiphysis -disc of hyaline cartilage that grows during childhood to lengthen the bone

Question 26

FONTANELS

Answer 26

SOFT SPOTS IN BABIES CRANIUM 1. anterior fontanel - largest, at junction of parietal and frontal bone (18-24 months) 2. posterior fontanel - junction at parietal and occipital bone (2 months) 3. anterolateral fontanel - laterally along frontal, temporal and sphenoid bone (3 months) 4. posterolateral fontanel - lateral along parietal, occipital and temporal bone (12 months)