Ch.6 - Bone

Question 1

What is spongy (cancellous) bone?

Answer 1

Honeycomb of trabeculae filled w red bone marrow

Question 2

What is compact (lamellar) bone?

Answer 2

Dense outer layer of bone

Question 3

What is trabeculae?

Answer 3

In spongy bone, the arches of the structure

Question 4

What minerals are stored in bone?

Answer 4

Calcium and phosphorus

Question 5

Texture of spongy (cancellous) bone?

Answer 5

Honeycomb, w trabeculae full of red bone marrow

Question 6

Texture of compact (lamellar) bone

Answer 6

Dense outer layer

Question 7

Structure of long bone (3)

Answer 7

Epiphysis
Metaphysis
Diaphysis

Question 8

What is yellow bone marrow?

Answer 8

Fat

Question 9

What is the diaphysis of long bone made of?

Answer 9

Compact bone, surrounding medullary cavity

Question 10

What is medullary cavity?

Answer 10

Inside of bone, hollow part of diaphysis

Question 11

Bone membranes (2)

Answer 11

Periosteum and endosteum

Question 12

Describe periosteum layers (2)

Answer 12

outer: where tendons + ligaments grab
Inner: allows creation of bone (osteoblasts + osteoclasts)

Question 13

What makes up periosteum?

Answer 13

Irregular connective tissue proper

Question 14

Components of periosteum

Answer 14

2 layers, 
nociceptors,
blood, 
lymphatic vessels, 
Sharpey fibers

Question 15

What are nociceptors

Answer 15

Nerve fibers signaling pain in periosteum

Question 16

What are sharpey’s fibers?

Answer 16

Collagen fibers attach periosteum to actual bone

Question 17

what does periosteum cover?

Answer 17

Everything but articular surfaces

Question 18

What covers articular surfaces?

Answer 18

Hyaline cartilage

Question 19

Where is epiphyses of long bone?

Answer 19

The top (proximal) and bottom (distal) ends

Question 20

What membrane covers epiphyses?

Answer 20

Hyaline cartilage

Question 21

Describe structure of epiphyses

Answer 21

Exterior is compact bone,

interior is spongy bone

Question 22

Where is metaphyses of bone

Answer 22

Neck of bone and epiphyseal plate

Question 23

What separates epiphyses from metaphyses?

Answer 23

Epiphyseal line (growth plate)

Question 24

What does endosteum cover

Answer 24

Internal surfaces of bone (trabeculae)

Question 25

what is structure of short, irregulars and flat bones?

Answer 25

Periosteum covered compact bone on outside of endosteum covered spongy bone

Question 26

What's normally inside irregular, flat, and short bones between the trabeculae?

Answer 26

Red bone marrow

Question 27

Where is yellow bone marrow found?

Answer 27

Medullary cavity of adult bones

Question 28

What's in yellow bone marrow?

Answer 28

Adipose tissue and some red marrow cells

Question 29

Where to find red marrow?

Answer 29

In spongy bone (skull, ribs, sternum, vertebrae, and most of pelvis, and proximal epiphysis of humerus and femur

Question 30

What's in red marrow?

Answer 30

Mostly red marrow cells (hematopoietic cells) in a reticular connective tissue proper

Question 31

What is an osteoid

Answer 31

Unmineralized bone matrix secreted by osteoblasts | Makes bone less brittle

Question 32

What are organic components of bone

Answer 32

Osteoblasts Osteoclasts Osteocytes Osteoid

Question 33

Inorganic component of bone

Answer 33

Mineral salts

Question 34

Function of inorganic component of bone (mineral salts)

Answer 34

Bone hardness and ability to resist compression

Question 35

What is an osteon? (Haversian system)

Answer 35

Compact ring around canal w BV + lymphatics

Question 36

What are canaliculi?

Answer 36

Hairlike canals, | Gap junctions allowing cell-cell connections (little cracks in compact bone)

Question 37

What's lamella

Answer 37

Weight-bearing, | column-like tubes of bone matrix rich in collagen,

Question 38

Components of cancellous bone

Answer 38

``` Osteoblasts Osteoblasts Osteocytes Canaliculi Lamellae ```

Question 39

Formation of bony skeleton (2)

Answer 39

Intramembranous ossification | Endochondral ossification

Question 40

Describe intramembranous ossification

Answer 40

Bone develops from fibrous membrane

Question 41

Where would you see intramembranous ossification

Answer 41

Skull, mandible, and clavicles

Question 42

Describe endochondral ossification

Answer 42

Bones forms from hyaline cartilage

Question 43

Where would you see endochondral ossification

Answer 43

All bones of skeleton Below base of skull (except clavicles)

Question 44

Functional zones in longitudinal bone growth (4)

Answer 44

Quiescent zone Proliferating zone Hypertrophic zone Calcification zone

Question 45

Describe quiescent zone

Answer 45

(resting), cartilage anchors growth plate to epiphysis

Question 46

Describe proliferating zone

Answer 46

Cartilage cells are active, | Pushing epiphysis away from diaphysis (lengthening)

Question 47

Describe Hypertrophic zone

Answer 47

Older cartilage cells dying, | Expanding of proliferating cells

Question 48

Describe calcification zone

Answer 48

New bone formation

Question 49

What is appositional bone growth

Answer 49

Bone increases in thickness in response to stress

Question 50

What happens during appositional bone growth

Answer 50

2 layers of periosteum separate, | Periosteum becomes endosteum

Question 51

What cells remodel bones

Answer 51

Osteoclasts break it down, osteoblasts rebuild

Question 52

What cells do bone resorption

Answer 52

Osteoclasts, they secrete: hydrochloric acid = concert calcium salts into soluble forms Lysosomal enzymes = digest organic matrix

Question 53

What is transcytosis

Answer 53

Osteoclasts release lysosome into interstitial fluid, then Ca+ into blood stream

Question 54

What is Wolf's Law

Answer 54

Bone remodels/grows in response to stress

Question 55

Ways Ca2+ is necessary:

Answer 55

``` Transmit nerve impulses Muscle contraction Blood clotting Gland secretion Cell division ```

Question 56

Describe Ca2+ homeostasis process of treating hypercalcemia

Answer 56

Thyroid release calcitonin, | Inhibits osteoclasts and inc osteoblasts

Question 57

Describe Ca2+ homeostasis process of fixing hypocalcemia

Answer 57

Parathyroid releases parathyroid hormone, | Stimulates osteoclasts = breaking bone down and releasing stored calcium