Chapter 6 (M&k)

Front 1

Skeletal Cartilage

Back 1

Made of some variety of cartilage tissue molded to fit its body location and function

Consists primarily of water, which accounts for its resilience, its ability to spring back to its original shape

Front 2

What is cartilage surrounded by? What does it not contain?

Back 2

It is surrounded by a layer of dense irregular connective tissue

It has no nerves or blood vessels

Front 3

Perichondrium

Back 3

around the cartilage

contains blood vessels which nutrients diffuse through the matrix to reach the cartilage cells interally

Front 4

What are the 3 types of cartilage tissue?

Back 4

Hyaline, Elastic, Fibrocartilage

Front 5

What are the basic components of the 3 types of cartilage tissue?

Back 5

cells called Chondrocytes encased in small cavities within an extracellular matrix containing a jelly-like substance and fibers

Front 6

Hyaline Cartilage

Back 6

look like frosted glass when freshly exposed

provide support with flexibility and resilience

most abundant skeletal cartilages

their chondrocytes are spherical

the only fiber type in their matrix is fine collagen fibers

Front 7

What are the four types of hyaline cartilage?

Back 7

articular cartilage (moveable joints), costal cartilage (ribs), respiratory cartilage (form the skeleton of the larynx), nasal cartilage (support external nose)

Front 8

Elastic Cartilage

Back 8

resemble hyaline cartilage,

contain more stretchy elastic fibers, this makes them better able to stand up to repeated bending,

found in 2 skeletal locations-the external ear & epiglottis

Front 9

Fibrocartilage

Back 9

Highly compressible with great tensile strength,

consist of roughly parallel rows of chondrocytes,

occur in the sites that are subjected to both pressure and stretch, such as the pad like cartilages in the knee and the disks between the vertebrae

Front 10

Cartilage

Back 10

has a flexible matrix that can accommodate mitosis,

is the ideal tissue to use to rapidly lay down the embryonic skeleton and to provide for new skeletal growth

Front 11

What two ways do cartilage grow?

Back 11

Appositional growth: cartilage forming cells in the surrounding perichondrium secrete new matrix against the external face of the existing cartilage tissue

Interstitial growth: the lacunae found chondrocytes divide and secrete new matrix expanding the cartilage from within

Front 12

When does cartilage growth end?

Back 12

During adolescence when the skeleton stops growing

Front 13

What happens when a bone becomes calcified?

Back 13

It is hardened due to the deposit of calcium salts... it does NOT become a bone!!

Front 14

What are the 7 important functions our bones produce?

Back 14

1. Support

2. Protection

3. Anchorage

4. mineral and growth factor storage

5. bone cell formation

6. triglyceride storage

7. hormone production

Front 15

Hematopoiesis

Back 15

blood cell formation, occurs in the red marrow cavities of certain bones

Front 16

What does the osteocalcin hormone produced by bone help regulate and protect against?

Back 16

It helps regulate insulin secretion, glucose homeostasis, and energy expenditure.

It protects against obesity, glucose intolerance, and diabetes.

Front 17

What are the two most common minerals produced by bone?

Back 17

calcium and phospate

Front 18

How many bones are there in the human body?

Back 18

206

Front 19

What are the 2 groups bones are divided into?

Back 19

Axial and Appendicular

Front 20

The Axial Skeleton

Back 20

forms the long axis of the body

includes the bones of the skull, vertebral column, and the rib cage

these bones protect, support, or carry other body parts

Front 21

The Appendicular Skeleton

Back 21

consists of the bones of the upper and lower limbs and the gurdles that attach the limbs to the axial skeleton

Front 22

Long Bones

Back 22

considerably longer than they are wide, has a shaft and two ends

Front 23

What bones are NOT long bones?

Back 23

patella, wrist, and ankle bones

ALL LIMB BONES ARE LONG BONES

Front 24

Short Bones

Back 24

roughly cube shaped, the bones of the wrist and ankle are examples, DO NOT have a shaft or an epiphyses

Front 25

What are sesamoid bones?

Back 25

A special type of short bone that form in the tendon, for example the patella.

Front 26

Flat bones

Back 26

Bend, Flattened, and usually a bit curved. The sternum, scapulau, ribs and most skull bones are flat bones. They consist of a layer of spongy bone sandwiched between two thin layers of compact bone.

Front 27

Irregular Bones

Back 27

They have complicated shapes that fit in none of the preceding classes. Examples include the vertebrae and the hip bones.

Front 28

Why are bones considered organs?

Back 28

Because they contain different types of tissue.

Front 29

What do bones contain?

Back 29

Osseous tissue, nervous tissue in their nerves, cartilage in their articular cartilages, dense connective tissue covering their external surface, and muscle and epithelial tissues in their blood vessels.

Front 30

What are the three levels of bone structure?

Back 30

1. Gross

2. Microscopic

3. Chemical

Front 31

What does every bone have in common?

Back 31

Every bone has a dense outer layer that looks smooth and solid to the naked eye. This external layer is compact bone.

Front 32

Compact bone

Back 32

external layer that looks smooth and solid to naked eye in every bone

Front 33

Spongy bone

Back 33

Internal to the compact bone, also called the trabecular bone, and it is a honeycomb of small needle-like flat pieces called trabeculae.

Front 34

In living bones, what are the open spaces between the tribeculae filled with?

Back 34

Red or yellow bone marrow.

Front 35

What do short irregular and flat bones share?

Back 35

They all consist of thin plates of spongy bone covered by compact bone.

Front 36

Diaphysis

Back 36

tubular shaft, forms long access of bone,constructed of a relatively thick collar of compact bone that surrounds a central medullary cavity or marrow cavity. In long bones.

Front 37

long bones

Back 37

All have general structure: a shaft, bone ends, and membranes. There is one diaphysis and 2 epiphyses.

Front 38

In adults, the medullary cavity contains what?

Back 38

It contains fat and is called the yellow marrow cavity.

Front 39

Epiphyses

Back 39

The bone ends. In many cases they are broader than the diaphyses. outer shell of compact bone forms the exterior and the interior contains spongy bone. A thin layer of articular hyaline cartilage covers each joint surface.

Front 40

Where is the growth plate in long bones located?

Back 40

The epiphyseal plate.

Front 41

Epiphyseal line

Back 41

Located between the diaphyses and each epiphyses of an adult long bone. it is a disk of hyaline cartilage that grows during childhood to lengthen the bone.

Front 42

Periosteum

Back 42

-glistening white double layered membrane

-covers the external surface of the entire bone except for joint surfaces

-richly supplied with nerve fibers and blood vessels that pass through the shaft to enter the marrow cavity via a nutrient foramen

-Provides anchoring points for tendons and ligaments

Front 43

The outer fibrous layer of the periosteum

Back 43

Dense irregular connective tissue

Front 44

The inner ostiogenic layer

Back 44

located next to the bone surface and consists primarly of primitive stem cells, osteogenic cells, that give rise to all bone cells except bone destroying cells.

Front 45

Perferating (sharpeys) fibers

Back 45

tufts of collagen fibers that extend from its fibrous layer into its bone matrix. they secure the periosteum to the underlying bone.

Front 46

Bones broken in the __________ heal easier

Back 46

Diaphyses

Front 47

Endosteum

Back 47

A delicate connective tissue membrane that covers internal bone surfaces. It covers the tribiculae of spongy bone and lines the canals that pass through spongy bones.

Front 48

What do the periosteum and the endosteum have in common?

Back 48

They both cover bones and they both have osteogenic cells that can differentiate between other bone cells.

Front 49

Red marrow

Back 49

Also called hematopoietic tissue. It is typically found in the tribicular cavity of spongy bone of long bones and in the diploe of flat bones. For this reason, both these cavities are often called red marrow cavities. Red marrow makes red blood cells. It is in the epiphyses

Front 50

In new born infants, the medullary cavity of the diaphyses and all areas of the spongy bone contain what?

Back 50

Red bone marrow

Front 51

In adult bones, how much red marrow is present in spongy bone cavities?

Back 51

very little. For this reason, blood cell production in adult long bones routinely occurs only in the heads of the femur and humerus.

Front 52

The red marrow found in the diploe of flat bones and some irregular bones are ___________ in Hematopoiesis?

Back 52

much more active

Front 53

If a person becomes anemic and needs more red blood cells, what can happen?

Back 53

yellow marrow in the medullary cavity can revert to red marrow

Front 54

What are projections?

Back 54

bone markings that bulge outward from the surface-include heads, trochanters, spines, and others

Front 55

What are the five major cell types that populate bone tissue?

Back 55

Osteogenic cells

Osteoblasts

Osteocytes

Bone lining cells

Osteoclasts

Front 56

Osteogenic cells

Back 56

aka osteoprogenic cells

mitotically active stem cells found in the membranous periosteum and endosteum

Front 57

Osteoblasts

Back 57

bone-forming cells that secrete the bone matrix; actively mitotic

Front 58

Osteocytes

Back 58

-mature bone cells that occupy spaces (lacunae) that conform to their shape

-monitor and maintain the bone matrix

-act as stress or strain "sensors" and respond to mechanical stimuli

-communicate this info to osteoblasts and osteoclasts so that bone matrix can be made or degraded as necessary to preserve calcium homeostasis

Front 59

Bone lining cells

Back 59

-flat cells found on bone surfaces where bone remodeling is not going on

-also thought to help maintain the matrix

-called periosteal cells if they are located on the external bone surface

-called endosteal cells if they are located on the internal surface

Front 60

Osteoclasts

Back 60

giant multinucleate cells located at sites of bone resorption

when active they display a ruffled border which increases surface area for enzyme degradation of bone and seals off area surrounding matrix

Front 61

Osteon (Haversian System)

Back 61

-the structural unit of compact bone

-each osteon is an elongated cylinder oriented parallel to the long axis of the bone

-tiny weight bearing pillars

-designed as a "twister resister"

Front 62

Osteon

Back 62

Front 63

Central canal (Haversian Canal)

Back 63

runs through the core of each osteon

contains small blood vessels and nerve fibers that serve the osteon's cells

Front 64

Perforating canals (Volkmann's canals)

Back 64

-lie at right angles to the long axis of the bone and connect the blood and nerve supply of the medullary cavity to the central canals

-lined with endosteum

-larger ones that connect everything together

Front 65

Interstitial lamellae

Back 65

incomplete lamellae that lie between intact osteons in compact bone

Front 66

Circumferential lamellae

Back 66

-located just deep to the periosteum and just supericial to the endosteum

-extend around the entire circumference of the diaphysis and effectively resist twisting of the long bone

Front 67

Hydroxyapatites

Back 67

mineral salts

Front 68

Organic components

Back 68

include bone cells and osteoid

Front 69

inorganic components

Back 69

mineral salts

Front 70

How strong is healthy bone?

Back 70

-1/2 as strong as steel in resisting compression

-fully as strong as steel in resisting tension

Front 71

Ossification

Back 71

-synonym: osteogenesis

-the process of bone formation

-in embryos, this leads to the formation of the bony skeleton

-ossification in adults serves mainly for bone remodeling and repair

Front 72

endochondral ossification

Back 72

-a bone develops by replacing hyaline cartilage

-the resulting bone is called a cartilage, or endochondral, bone

-forms essentially all bones below the base of the skull except for the clavicles

Front 73

intramembranous ossification

Back 73

a bone develops from a fibrous membrane and the bone is called a membrane bone

Front 74

primary ossification center

Back 74

a region in the center of the hyaline cartilage where long bone formation begins

Front 75

5 steps of endochondral ossification

Back 75

1. A bone collar forms around the diaphysis of the hyaline cartilage model.

2. Cartilage in the center of the diaphysis calcifies and then develops cavities.

3. The periosteal bud invades the internal cavities and spongy bone forms.

4. The diaphysis elongates and a medullary cavity forms.

5. The epiphyses ossify.

Front 76

Intramembranous ossification

Back 76

forms the cranial bones of the skull (frontal, parietal, occipital, and temporal bones) and the clavicles

most bones formed by this are flat bones

Front 77

Figure 6.10

Growth in length of a long bone occurs at the epiphyseal plate.

Back 77

Front 78

During infancy and childhood, what is the single most important stimulus of epiphyseal plate activity?

Back 78

growth hormone released by the anterior pituitary gland

Front 79

What two processes constitute bone remodeling?

Back 79

bone deposit and bone resorption

Front 80

osteoid seam

Back 80

an unmineralized band of gauzy-looking bone matrix 10-12 micrometers wide

marks areas of new matrix deposits by osteoblasts

Front 81

calcification front

Back 81

an abrupt transition between the osteoid seam and the older mineralized bone

Front 82

remodeling units

Back 82

"packets" of adjacent osteoblasts and osteoclasts that coordinate bone remodeling

Front 83

Parathyroid hormone (PTH)

Back 83

produced by the parathyroid glands

primarily involved in the hormonal controls

Front 84

Hormonal Controls

Back 84

Front 85

Wolff's Law

Back 85

holds that a bone grows or remodels in response to the demands placed on it

Front 86

Nondisplaced vs Displaced Fractures

Back 86

Nondisplaced: the bone ends retain their normal position

Displaced: the bone ends are out of normal alignment

Front 87

Complete vs Incomplete Fractures

Back 87

Complete: if the bone is broken through

Incomplete: if it is NOT broken through

Front 88

Open vs Closed fractures

Back 88

Open (compound): when the bone ends penetrate the skin

Closed (simple): when the bone ends do NOT penetrate the skin

Front 89

Reduction

Back 89

the realignment of the broken bone ends

Front 90

Closed vs open reduction

Back 90

Closed (external): the physician's hands coax the bone ends into position

Open (internal): the bone ends are secured together surgically with pins or wires

Front 91

4 stages of repair in a simple fracture

Back 91

1. A hematoma forms.

2. Fibrocartilaginous callus forms

3. Bony callus forms

4. Bone remodeling occurs

Front 92

Common types of fractures

Back 92

Comminuted: bone fragments into three or more pieces

Compression: bone is crushed

Spiral: ragged break from excessive twisting

Epiphyseal: epiphysis separates from the diaphysis along the epiphyseal plate

Depressed: broken bone portion is pressed inward

Greenstick: bone breaks incompletely

Front 93

Osteomalacia

Back 93

includes a number of disorders in which the bones are poorly mineralized

Front 94

Rickets

Back 94

the analogous disease in children

Front 95

Osteoporosis

Back 95

refers to a group of diseases in which bone resorption outpaces bone deposit

Front 96

Paget's Disease

Back 96

characterized by excessive and haphazard bone deposit and resorption

Front 97

Pagetic bone

Back 97

is hastily made and has n abnormally high ratio of spongy bone to compact bone