Bone Histology

Question 1

what is the matrix of cartilage composed of?

Answer 1

type II collagen

Question 2

name the two matrices of collagen

Answer 2

territorial

interterritorial

Question 3

describe territorial cartilage matrix

Answer 3

adjacent to chondrocytes…poor in collagen

Question 4

where is interterritorial collagen matrix located?

Answer 4

further from chondrocytes and has more collagen

Question 5

which of interterritorial and territorial matrices stains dark?

Answer 5

territorial

Question 6

what are chondrocytes embedded in?

Answer 6

lacunae within the matrix

Question 7

where are most chondroblasts located?

Answer 7

in the perichondrium

Question 8

what is the perichondrium? what is it made of?

Answer 8

layer of dense irregular connective tissue surrounding hyaline and elastic cartilage

Question 9

what type of cartilage doesnt have perichondrium?

Answer 9

fibrocartilage

Question 10

what are the two types of cartilage growth?

Answer 10

interstitial and appositional

Question 11

what is interstitial cartilage growth?

Answer 11

existig chondrocytes make more chondrocytes

Question 12

where is a common place for interstitial cartilage growth to occur?

Answer 12

epiphyseal plates of bone

Question 13

what is appositional growth of cartilage?

Answer 13

chndrogenic cells become chondroblast then chondroblasts become chondrocytes

Question 14

where does appositional growth of cartilage occur?

Answer 14

in perichondrium

Question 15

hyaline cartilage has what type of collagen?

Answer 15

type II

Question 16

elastin cartilage has what type of collagen?

Answer 16

type II

Question 17

fibrocartilage has what type of collagen?

Answer 17

type I

Question 18

which two types of cartilage have perichondrium?

Answer 18

hyaline and elastin

Question 19

name three common places for elastin cartilae

Answer 19

ear, epiglottis, laryngeal cartilages

Question 20

where is hyaline cartilage found?

Answer 20

articular ends of bones, respiratory system

Question 21

where is fibrocartilage found?

Answer 21

IV discs, insertion of tendons, meniscus

Question 22

name the two matrices of bone

Answer 22

inorganic

organic

Question 23

the inorganic matrix of bone mainly has what in it?

Answer 23

calcified tissue

Question 24

the organic matrix of bone has what in it?

Answer 24

type I collagen

Question 25

what cell differentiates into osteoblasts?

Answer 25

osteoprogenitor cells

Question 26

what shape are osteoblast when active? what about inactive?

Answer 26

cuboidal when active and flat when inactive

Question 27

what do osteoblasts secrete?

Answer 27

osteiod

Question 28

what is osteiod?

Answer 28

uncalcified bone matrix...type 1 collagen

Question 29

what is an osteocyte?

Answer 29

when osteoblast gets entrapped in its own matrix

Question 30

how do osteocytes communicate?

Answer 30

through gap junctions via their caniliculi

Question 31

what is osteoclasts role? where do they reside?

Answer 31

break down bone...reside in Howships lacunae

Question 32

what is a Howship lacunae?

Answer 32

depressions representing bone resorption

Question 33

what color is cytoplasm of osteoclasts?

Answer 33

very pink

Question 34

PTH stimulates bone growth or resorption?

Answer 34

resorption

Question 35

name the four zones of an osteoclast

Answer 35

basal zone ruffled border clear zone vesicular zone

Question 36

what happens at the ruffled border?

Answer 36

this is the active site of resorption

Question 37

what is the clear zone of a osteoclast used for?

Answer 37

actin filaments to maintain contact with bone that is being resorbed

Question 38

what are the three steps of bone resorption?

Answer 38

acid release from osteoclasts different enzymes degrade bone osteoclasts resorb everything

Question 39

what is the periosteum?

Answer 39

outer layer of bone that is not calcified and makes articulations

Question 40

what are sharpey fibers in the periosteum?

Answer 40

they are the type I collagen fibers that connect the periosteum to the underlying bone

Question 41

what is the endosteum?

Answer 41

thin inner connective tissue layer that lines the bone marrow cavity

Question 42

what does the endosteum provide to the marrow cavity?

Answer 42

osteoprogenitor cells and osteoblasts

Question 43

what is spongy bone composed of?

Answer 43

interconnected trabeculae which surround cavities filled with bone marrow

Question 44

what are the trabeculae of spongy bone made of?

Answer 44

osteocytes and osteoblasts on each surface

Question 45

what is spongy bone surrounded by?

Answer 45

compact bone

Question 46

what does primary bone mainly have in it?

Answer 46

many osteocytes with irregulary arranges type I collagen bundles...and low mineral content

Question 47

what is primary bone replaced by?

Answer 47

secondary bone

Question 48

what is secondary bone made of?

Answer 48

calcified matrix arranged in regular lamellae with osteocytes in lacunae

Question 49

what are the long cylindrical structures that run parallel to bone axis in bone?

Answer 49

haversian systems or canals

Question 50

what connects different haversian canals?

Answer 50

Volkmann channels

Question 51

what surrounds haversian canals?

Answer 51

lamellae

Question 52

what are interstitial lamellae?

Answer 52

irregularly shaped lamellae that are between haversian canals...remnants of old bone

Question 53

what are the five zones of cartilage at epiphyseal plates?

Answer 53

``` zone of reserve proliferation maturation and cell hypertrophy calcification ossification ```

Question 54

what happens in zone of reserve?

Answer 54

regular cartilage is there

Question 55

what happens in zone of proliferation? how does it look?

Answer 55

rapid mitotic division of chondrocytes..stacked on each other

Question 56

what happens in zone of maturation and hypertrophy?

Answer 56

cells grow in size and get ready to die

Question 57

what happens in zone of calcification?

Answer 57

chondrocytes die and get calcified

Question 58

what happens in zone of ossification?

Answer 58

osteoblasts start dropping some bone matrix around calcified cartilage

Question 59

what movement occurs in synarthroses joints?

Answer 59

NONE

Question 60

what movement occurs in diarthroses joints? what is another name?

Answer 60

maximum movement....synovial joints

Question 61

name two joint types

Answer 61

synarthroses and diarthroses

Question 62

what are the two layers of an articular cavity in a joint?

Answer 62

fibrous capsule | internal synovial capsule

Question 63

what are the two cell types of internal synovial capsule in joint?

Answer 63

Type A and B

Question 64

what do type A synovial capsule joint cells do?

Answer 64

phagocytic

Question 65

what do type B synovial capsule joint cells do?

Answer 65

secrete synovial fluid and serve as fibroblasts