Lesson 2

Question 1

What is the ECM made up of?

Answer 1

Water, collagen fibers (organic), and crystallized mineral salts (inorganic)

Question 2

What makes up the ECM the least and most?

Answer 2

15% water, 55% crystallized mineral salts

Question 3

What secretes collagen fibers?

Answer 3

Osteoblasts

Question 4

What do osetoblasts secrete?

Answer 4

Collagen fibers

Question 5

What purpose do collagen fibers serve?

Answer 5

Prevent bone shattering

Question 6

What would happen if bone was only made up of crystallized mineral salts?

Answer 6

Bones could shatter upon harsh impact

Question 7

What cells are in osseous tissue?

Answer 7

Osteogenic cells
Osteoblast cells
Osteocyte cells
Osteoclast cells

Question 8

Where are osteogenic cells found in higher densities?

Answer 8

Outer bone surfaces and in the medullary cavity

Question 9

Where are osteoblast cells found in higher densities?

Answer 9

Outer bone surfaces and in the medullary cavity

Question 10

What cells develop into osteoblasts?

Answer 10

Osteogenic cells

Question 11

What do osteogenic cells develop into?

Answer 11

Osteoblasts

Question 12

What cells build bone?

Answer 12

Osteoblasts

Question 13

What do osteoblasts do?

Answer 13

Build bone

Question 14

What cells are mature bone cells?

Answer 14

Osteocytes

Question 15

What do osteocytes do?

Answer 15

Communicate with other osteocytes to upkeep with daily metabolism of bone tissue

Question 16

What do osteoclasts do?

Answer 16

Breakdown bones via lysosomal enzymes

Question 17

Which of the cells in the osseous tissue are the biggest?

Answer 17

Osteoclasts

Question 18

What cells breakdown bone tissue?

Answer 18

Osteoclasts

Question 19

What cells communicate with osteocytes to upkeep with the daily metabolism of bone tissue?

Answer 19

Osteocytes

Question 20

What is the life cycle of osseous tissue?

Answer 20

Osteogenic cells→ osteoblasts→ osteocytes

Question 21

What cells are not part of the life cycle of osseous tissue?

Answer 21

Osteoclasts

Question 22

What are the 2 types of bone?

Answer 22

Spongy and compact

Question 23

What is compact bone also known as?

Answer 23

Dense or cortical bone

Question 24

What type of bone has strength in bending?

Answer 24

Compact bone

Question 25

What do compact bone have strength in?

Answer 25

Bending

Question 26

What type of bone forms the bulk of diaphysis of long bones?

Answer 26

Compact bones

Question 27

What bone is the longest of long bones?

Answer 27

Femur

Question 28

What does compact bone consist of?

Answer 28

Neighbouring osteons/Harvesian systems

Question 29

How are osteons aligned in compact bone?

Answer 29

In the same direction along stress lines

Question 30

What are concentric lamellae in osetons?

Answer 30

Mineralized ECM with osteocytes

Question 31

What are lacunae in osteons?

Answer 31

Spaces between lamellae

Question 32

What are canliculi in osteons?

Answer 32

Lacunae extensions

Question 33

What are interstitial lamellae in osteons?

Answer 33

Old osteon fragments to be removed from the bone

Question 34

What is the central canal in osteons?

Answer 34

A passageway for neurovasculature and lymphatics

Question 35

What cells do cicumferential lamellae have lots of?

Answer 35

Osteogenic and osteoblast cells

Question 36

What are circumferential lamellae important for?

Answer 36

Bone width growth or appositional growth

Question 37

What is the end part of a long bone called?

Answer 37

Epiphysis

Question 38

What is the epiphysis?

Answer 38

The end of a long bone

Question 39

What is the diaphysis?

Answer 39

The middle of a long bone

Question 40

What is the middle of a long bone called?

Answer 40

Diaphysis

Question 41

What is the metaphysis?

Answer 41

The part of the long bone between the epiphysis and diaphysis

Question 42

What is the part of the long bone between the epiphysis and diaphysis called?

Answer 42

Metaphysis

Question 43

What is the epiphyseal plate of a long bone made up of?

Answer 43

Hyaline cartilage

Question 44

When do bones stop growing in length for males and females?

Answer 44

21 in males and 18 in females

Question 45

What is the hyaline cartilage replaced by?

Answer 45

Bone at 21 in males and 18 in females resulting in the bones stop growing in length

Question 46

Where is articular cartilage located?

Answer 46

On the ephiphysis

Question 47

What does the articular cartilage do?

Answer 47

Helps with shock absorption

Question 48

Why does articular cartilage not heal well?

Answer 48

B/c it does not have high blood supply

Question 49

What is the periosteum?

Answer 49

An outer connective tissue layer that surrounds all bones (except where there is articular cartilage)

Question 50

What surrounds all bones except where there is articular cartilage?

Answer 50

Periosteum

Question 51

What is the periosteum adhered to?

Answer 51

Circumferential lamellae

Question 52

What are the periosteum layers like?

Answer 52

Outer fibrous layer Inner osteogenic layer

Question 53

What lies within the periosteum and is lined by endosteum?

Answer 53

Medullary cavity

Question 54

What fibers allow close adherence between the periosteum and the compact bone?

Answer 54

Perforating/Sharpey’s fibers

Question 55

What canals perforate the periosteum and compact bone to allow neurovasculature to enter?

Answer 55

Perforating/Volkmann's canals

Question 56

What is spongy bone also known as?

Answer 56

Trabecular or cancellous bone

Question 57

What type of bone has strength in compression?

Answer 57

Spongy bone

Question 58

What does spongy bone have strength in?

Answer 58

Compression

Question 59

What type of bone forms the bulk of epiphysis of long bones and short, flat, irregular bones?

Answer 59

Spongy bone

Question 60

What does spongy bone do?

Answer 60

Protects the marrows and reduces bone weight