Bones Part 1

Question 1

What are the 5 functions of the skeletal system

Answer 1

1. protection
2. support
3. blood cell formation
4. aid in movement
5. storage of minerals

Question 2

ligaments

Answer 2

connect bone to bone

Question 3

tendons

Answer 3

connect muscle to bone

Question 4

what cells make up cartilage

Answer 4

chondroblasts and chondrocytes

Question 5

what are chondrocytes

Answer 5

mature cells that maintain the matrix

Question 6

what are chondroblasts

Answer 6

active cells that produce the matrix

Question 7

what are the main components of cartilage

Answer 7

extracellular matrix, cells, and perichondrium

Question 8

what is the extracellular matrix of cartilage

Answer 8

gel-like ground substance rich in water that allows cartilage to be highly compressible

Question 9

why is cartilage matrix more compressible than bone matrix

Answer 9

it doesn’t have calcium

Question 10

what do collagen and elastin have to do with cartilage

Answer 10

these fibrous proteins reinforce the matrix (like a rebar)

Question 11

what is GAG

Answer 11

sulfated carbohydrates attached to protein core

Question 12

what does GAG have to do with cartilage

Answer 12

negative sulfated groups hold water which is part of the cushion

Question 13

what features are missing from cartilage matrix

Answer 13

no nerves or vessels (relies on diffusion of waste and nutrients)

Question 14

what are the layers of the perichondrium

Answer 14

outer fibrous connective tissue (with blood vessel)

inner cellular layer (chondrogenic layer)

Question 15

what and where is the most abundant skeletal cartilage

Answer 15

hyaline cartilage

articular, costal, and nasal

Question 16

what and where is elastic cartilage

Answer 16

most flexible due to large amount of elastin

in external ear and epiglottis

Question 17

what and where is fibrocartilage

Answer 17

helps connect your ligaments to bone

knee and intervertebral discs

Question 18

because fibrocartilage is reinforced with thick collagen, compared to other cartilage it is

Answer 18

most pressure and stretch resistant

Question 19

what are the main components of bone tissue

Answer 19

cells (living) and extracellular matrix (nonliving)

Question 20

osteoprogenitor cell function

Answer 20

stem cells that generate cells that mature to become osteoblasts

Question 21

osteoprogenitor cell location

Answer 21

bone surface

Question 22

osteoblast location

Answer 22

bone surface

Question 23

osteoblast function

Answer 23

produce osteoid

Question 24

osteoid

Answer 24

initial semisolid form of bone matrix that later mineralizes

Question 25

osteocyte location

Answer 25

trapped inside bone

Question 26

osteocyte function

Answer 26

maintain bone matrix and regulating activity of osteoblasts and osteoclasts

Question 27

osteoclast location

Answer 27

bone surface

Question 28

osteoclast function

Answer 28

bone resorption

Question 29

canaliculi

Answer 29

narrow tunnels through bone matrix that connect neighboring lacunae and central canal permitting intercellular contact

Question 30

periosteocytic space

Answer 30

the volume of fluid-filled space between the oseocyte and the wall of the lacuna

Question 31

inorganic portion of bone matrix

Answer 31

various salt crystals, hydroxyapatite, are deposited around collagen fibers and give it hardness

Question 32

organic portion of bone matrix

Answer 32

the 90% collagen (rebar) that gives bone tissue strength and some flexibility

Question 33

how does insufficient calcium affect bones

Answer 33

flexible bones, bow legged

Question 34

how does loss of collagen affect bones

Answer 34

brittle bones

Question 35

bone resorption

Answer 35

break down of bone matrix components by osteoclasts

Question 36

how do osteoclasts break down bone matrix

Answer 36

release enzymes to digest organic matrix parts

release carbonic acid to dissolve inorganic calcium and phosphorus

Question 37

bone formation

Answer 37

secretion of osteoid by osteoblasts followed by mineralization, deposition of crystals

Question 38

what nutrients are needed for bone formation

Answer 38

vitamin C needed for secretion of osteoid

and vitamin D, calcium, and phosphate need for deposition of crystals

Question 39

lamellae

Answer 39

ring-like layer of bone tissue surrounding central canal

Question 40

function of canaliculi

Answer 40

allow transport of nutrients, gases, and wastes between blood vessels and osteocytes

Question 41

function of diaphysis

Answer 41

leverage and major weight support

Question 42

composition of diaphysis

Answer 42

outer layer is compact bone

inner layer is spongy bone

Question 43

medullary cavity

Answer 43

inside diaphysis

houses bone marrow (red in kids, yellow in adults)

Question 44

composition of epiphysis

Answer 44

outer layer is compact bone
inner layer is spongy bone
joint surface covered with hyaline cartilage (for shock absorption and to decrease friction)

Question 45

periosteum

Answer 45

lining around outside of bone

Question 46

endosteum

Answer 46

lining of medullary cavity inside bone

Question 47

metaphysis

Answer 47

region between epiphysis and diaphysis containing the epiphyseal plate

Question 48

epiphyseal plate

Answer 48

thin layer of hyaline cartilage that provides lengthwise bone growth; remnant in adults is called epiphyseal line

Question 49

cellular layer of periosteum

Answer 49

includes osteoprogenitor cells, osteoblasts, and osteoclasts

Question 50

fibrous layer of periosteum

Answer 50

protects; anchors blood vessels and nerves to bone surface; attachment site for ligaments and tendons

Question 51

cells in endosteum

Answer 51

osteoprogenitor cells, osteoblasts, osteoclasts

Question 52

red bone marrow contains

Answer 52

reticular tissue, connective tissue, immature blood cells, fat

Question 53

red bone marrow in kids

Answer 53

spongy bone and medullary cavity of long bones

Question 54

red bone marrow in adults

Answer 54

portion of axial skeleton, proximal epiphyses of humerus and femur