Anatomy -- Cartilage/bone

Front 1

Cartilage and Bone belong into what category of connective tissues?

Back 1

SUPPORTING Connective Tissue!

Front 2

3 Major Cell Types of Cartilage Tissue?

Back 2

Chondroblasts
Condrocytes
Chondroclasts

Front 3

"chondro"

Back 3

cartilage

Front 4

"blast"

Back 4

immature

**think "B" comes before "C" in the alphabet... therefore immature!**

Front 5

"cyte"

Back 5

mature

**Don't get confused with "clast" -- "cy" comes after "cl" in alphabet.. therefore more mature!**

Front 6

"clast"

Back 6

destroyer

Front 7

Chondroblasts

Back 7

-immature cartilage cells

** located in perichondrium **
-secrete (BLAST!) new cartilage layers to the periphery
-mature into chondrocytes

Front 8

Chondrocytes

Back 8

mature cartilage cells

** located within cartilage **
-surrounded by cartilage MATRIX
- secrete CARTILAGE from within the MATRIX (interstitial growth)

Front 9

Chondroclasts

Back 9

phagocytic (eater) cells

** located in perichondrium **
secrete acids and enzymes that DISSOLVE cartilage

Front 10

Characteristics of Cartilage Tissue

Back 10

stiff GEL specialized for resilience
- can resume its original shape after being bent, stretched, compressed -- to a limited extent
-SOLID without cavity
-AVASULAR -- not associated or supported by blood vessels
-surrounded by perichondrium

Front 11

Cartilage Tissue relies on what for nutrients?
How does this effect the cartilage?

Back 11

diffusion; limits thickness

Front 12

Does cartilage heal quickly or slowly? Why?

Back 12

very slowly-- b/c it's avasular and depends on diffusion for nutrients

Front 13

"peri"

Back 13

around

Front 14

Cartilage tissue is surrounded by what?

Back 14

perichondrium

-"peri-" = around
-"chondro-" = cartilage

Front 15

Cartilage tissue is a source of what 2 things?

Back 15

nutrients (blood vessels)
chondroblasts & chondroclasts

Front 16

How does cartilage tissue grow?

Back 16

interstitial ("from within")
AND
appositional ("layers added to outside")

Front 17

Describe the appositional growth process of cartilage tissue

Back 17

Cartilage layers are added to the periphery (like rings to a tree) by CHONDROBLASTS!
1) cells in the cellular layer of the perichondrium differentiate into chondroblasts

2) These chondroblasts secrete new matrix

3) As the matrix enlarges, more cells are incorporated; they are replaced by divisions of stem cells in the perichondrium.

Front 18

Describe the interstitial growth process of cartilage tissue

Back 18

Cartiliage is a GEL and therefore EXPAND FROM WITHIN by secretion of matrix by chondrocytes.

1) Chondrocyte undergoes division

2) As daughter cells secrete additional matrix, they move apart, expanding the cartilage from within.

Front 19

3 Tissues Types of Cartilage

Back 19

Hyaline Cartilage
Elastic Cartilage
Fibrocartilage

Front 20

Which type of cartilage is most common?

Back 20

Hyaline Cartilage

Front 21

Which type of cartilage reduces friction in synovial joints?

Back 21

Hyaline Cartilage

Front 22

Hyaline Cartilage Characteristics

Back 22

-most common type of cartilage
-provides a smooth surface for gliding -- therefore it reduces friction in synovial joints
-found on ARTICULAR surfaces - between ribs and sternum - as precursors to long bones
- matrix is smooth and glassy

Front 23

Which type of cartilage is found on articular surfaces, such as between the ribs and sternum?

Back 23

Hyaline cartilage

Front 24

Elastic Cartilage Characteristics

Back 24

- only cartilage that contains elastic fibers
- VERY flexible
- tolerates bending and streching without permanent distortion
- found in ear, larynx
-matrix FRAYED -- elastic fibers

Front 25

Fibrocartilage

Back 25

- Only cartilage that contains large collagen fiber bundles
- VERY durable and tough
- resists compression, good for shock absorbing and weight-bearing surfaces
- found in intervertebral disks, menisci of knee, pubic symphysis
- matrix is almost purely collagen fibers

Front 26

Which cartilage contains collagen fibers?

Back 26

Fibrocartilage

Front 27

Which cartilage is very durable and tough?

Back 27

Fibrocartilage

Front 28

What are some characteristics of bone tissue?

Back 28

- VERY hard and rigid - b/c of calcium salts that are deposited around collagen fibers -- nurtients cannots diffuse through its matrix to reach the cells -- must travels though channels of the bone.
- VERY VASULAR (many blood vessels)
- hollow (marrow cavity)
- appositional growth only ( layers added to outside)

Front 29

Periosteum

Back 29

the outer connective tissue wrapping
source of: BLOOD VESSELS, osteoblasts

Front 30

Endosteum

Back 30

the inner connective tissue wrapping
source of: blood vessels, osteoblasts, osteoclasts

Front 31

What are the 2 tissue types of bone?

Back 31

compact and cancellous or spongy bone

Front 32

Compact bones provides what for the skeleton?

Back 32

support

Front 33

Compact bone

Back 33

- lines long bones and skull bones
- provides support for the skeleton

Front 34

Cancellous or Spongy bone

Back 34

- In the marrow cavity of long bones and skull bones
-source of calcium
-source of RBCs and WBCs in adults

Front 35

What are the 3 major cells types of bone tissue?

Back 35

1) osteoblasts
2) osteocytes
3) osteoclasts

Front 36

Osteoblasts

Back 36

-immature bone cells
-secrete new bone layers around the periphery

Front 37

Osteocytes

Back 37

-mature bone cells
-live in lucunae (cavities) between lmellae (layers)
-connected to adjacent osteocytes - via filopodia (little foot processes) in canaliculi (little canals)
- receive nutrients from blood vessels
*** FUNCTION: Maintain bone calcium levels ***

Front 38

lacunae

Back 38

cavities

Front 39

lamellae

Back 39

layers

Front 40

What type of cell is found in the lacunae?

Back 40

osteocytes

Front 41

What is the function of osteocytes?

Back 41

To maintain bone calcium levels

Front 42

Osteoclasts

Back 42

- Phagocytic cells in the marrow cavity
FUNCTION: secrete acids and enzymes that DISSOLVE bone

Front 43

What is the function of osteoclasts?

Back 43

They secrete acids and enzymes that dissolve bone.

Front 44

What are the 2 ways bones can develop?

Back 44

1) Intramembranous ossification
2) endochrondral ossification

Front 45

Intramembranous Ossificaton

Back 45

- bone development within a membrane
- the "membrane" is connective tissue
-skull bones develop this way

Front 46

How do skull bones develop?

Back 46

Intramembranous ossification

Front 47

Endochrondral ossification

Back 47

- bone development within a cartilage
-long bones develop this way
- bone "ossification" replaces cartilage "chondral" from within "endo"

Front 48

How do long bones develop?

Back 48

Endochrondral ossification

Front 49

Ossification

Back 49

the process by which a tissue is replaced by bone

Front 50

Describe the steps of Intramembranous Ossification

Back 50

Ossification within the membrane
1) stem cells within connective tissue differentiate into osteoblasts -- secrete spicules (projections) of bone matrix
2) Blood vessels grow intot he area to nourish the osteoblasts
3) With further development, bony spicules grow together and trap blood vessels inside the developing bone.
4) the bone matrix is remolded into compact bone at the periphery and spongy bone in the marrow cavity

Front 51

spicules

Back 51

projections

Front 52

Describe the steps of Endochondral Ossification

Back 52

-bone replaces cartilage from within

1) Chondrocytes form a hyaline cartilage model -- matrix calcifies (nutrients can no longer reach the chondrocytes -- they die) -- dead chondrocytes tigger other events
2) blood vessels grow around the edges of the cartilage model
3) Osteoblasts in the surrounding connective tissue secrete a collar of bone around the dying cartilage model -- becomes the compact bone of the diaphysis (shaft)
4) Blood Vessels enter the diaphysis accompanied by chondroclasts (destroy cartilage) and osteoblasts (secrete bone in its place) -- called PRIMARY OSSIFICATION CENTER
5) Osteoclasts destroy much of the bone, creating a marrow cavity -- meanwhile, the bony collar thickens as compact bone continues to be secreted around the diaphysis (shaft) via appositional growth
6) Blood Vessels, Chondroclasts, and osteoblasts enter the epiphyses (ends) -- SECONDARY OSSIFICATION CENTER -- this replaces the cartilage with bone at both ends of the bone as well.
7) Hyaline cartilage remains at the joint cavity to become teh articular cartilage of the synovial joint
8) Long bone growth ends at puberty, when cartilage at the metaphysis is replaced with bone

Front 53

When does long bone growth end?

Back 53

puberty

Front 54

What is the osteon?

Back 54

It is the basic unit of mature compact bone in long bones.

Front 55

What is the osteon composed of?

Back 55

It is composed of a central canal containing blood vessels. It is surrounded by concentric lamellae (layers) of bone. Between the lamellae are osteocytes.

Front 56

Bones continue to do what throughout your lifetime?

Back 56

remodel

Front 57

Homeostasis is achieved through...?

Back 57

bone addition and removal

Front 58

Osteoclasts _______ old bone and continue to ______ the marrow cavity

Back 58

destroy, enlarge

Front 59

Osteoblasts _______ new bone and continue to ______ new compact bone around the ______.

Back 59

produce, secrete, periphery

Front 60

What are the effects of exercise on the bones?

Back 60

- essential to bone strength and mass -- when you don't use, you lose!

-Up to 1/3 of bone mass can be lost in a few weeks of inactivity

** exercise causes osteoblasts to build bone! **

-inactivity causes bones to become weak - osteoporosis!

Front 61

Bone become _____ and _____ with age.

Back 61

thinner, weaker

Front 62

_______ begins between ages 30 and 40.

Back 62

Osteopenia

Front 63

Osteopenia

Back 63

reduction in bone mass

Front 64

Osteoporosis

Back 64

bones become porous

Front 65

Which bones are most affected by osteopenia and osteoporosis?

Back 65

epiphyses, vertebrae, jaw

Front 66

Bone loss _____ after menopause.

Back 66

accelerates

Front 67

What hormones help maintain bone mass?

Back 67

estrogen and androgen

Front 68

What mineral is most abundant in the body?

Back 68

calcium

Front 69

Bones store _____ as well as other minerals.

Back 69

calcium

Front 70

Calcium ions are vital to the proper functioning of what?

Back 70

neurons, muscle cells (heart cells)

Front 71

The cell type in cartilage that dissolves cartilage matrix is the...

Back 71

A. the chondroblast
B. the osteocyte
C. the chondroclast
D. the fibroblast
E. the osteoclast

Hint 71

C. the chondroclast

Front 72

All of the following are characteristics of cartilage EXCEPT...

Back 72

A. It is solid
B. It is avasular
C. It is surrounded by perichondrium.
D. It can only grow by addition of layers to the periphery
E. It has a gel-like consistency

Hint 72

D. It can only grow by addition of layers tot he periphery

Front 73

Which type of cartilage is best suited for shock-absorbing surfaces?

Back 73

A. hyaline
B. elastic
C. fibrocartilage
D. A and B
E. A, B, and C

Hint 73

C. fibrocartilage

Front 74

Which cell type produces new bone?

Back 74

A. osteoblast
B. chondroblast
C. osteocyte
D. chondrocyte
E. osteoclast

Hint 74

A. osteoblast

Front 75

An osteon ...

Back 75

A. Is the basic unit of compact bone
B. contains blood vessels
C. Is composed of lamellae of bone
D. contains osteocytes
E. All of the above

Hint 75

E. All of the above

Front 76

Concerning endochondral ossification...

Back 76

A. It begins with a cartilage model
B. It is how skull bones develop
C. It continues to occur through adulthood.
D. Elastic cartilage is replaced by bone
E. All of the above

Hint 76

A. It begins with a cartilage model