Musculoskeletal System

Front 1

Cartilage

Back 1

- Type of connective tissue composed of a chondril (elastic matrix) secreted by chondrocytes
- avascular and devoid of nerves
-receives nutrients by capillaries of nearby connective tissue and bone via diffusion

Front 2

Bone

Back 2

- mineralized connective tissue

Front 3

Compact bone

Back 3

- dense bone matrix
- contains hydroxyapatite crystals

Front 4

Spongy bone

Back 4

- less dense bone
- has spicule latice with yellow and/or red bone marrow filled between spicules

Front 5

yellow bone marrow

Back 5

- inactive
- contains adipose tissue

Front 6

red bone marrow

Back 6

- for red blood cell formation

Front 7

long bones

Back 7

- have fiaphysis and epiphyses

Front 8

diaphysis

Back 8

- in long bone
- mostly compact bone surrounding a cavity of bone marrow

Front 9

epiphyses

Back 9

- in long bone
- composed of spongy bone surrounded by thin layer of compact bone

Front 10

epiphyseal plate

Back 10

- disk of cartilaginous cells separating diaphysis from the epiphysis
- site of longitudinal growth

Front 11

periosteum

Back 11

- fibrous sheath surrounding long bone
- site of attachment to muscle tissue
- some periosteum cells differentiate into bone-forming cells

Front 12

structural units of the bone matrix

Back 12

- osteons (Haversian systems)

Front 13

haversian canal

Back 13

- channel in each osteon for blood vessels and nerve fibers and lymph

Front 14

lamellae

Back 14

concentric circles surrounding each haversian canal in an osteon

Front 15

lacunae

Back 15

spaces in the matrix which house mature bone cells (osteocytes)

Front 16

osteocytes

Back 16

- mature bone cells
- involved in bone maintenance

Front 17

canaliculi

Back 17

- small canals the interconnect with each other and with the Hacersian canals
- allow for exchange of nutrients and wastes

Front 18

osteoblasts

Back 18

- build bone

Front 19

osteoclasts

Back 19

- destroy bone in bone resorption

Front 20

endochondral ossification

Back 20

- process of bone formation
- existing cartilage is replaced by bone
- long bone is made this way

Front 21

intramembranous ossification

Back 21

- process of bone formation
- mesenchymal connective tissue is transformed into and replaced by bone

Front 22

joints

Back 22

connective tissue structures that join bones together

Front 23

skeletal muscle

Back 23

- innervated by somatic nervous system
- mutlinucleated
- voluntary
- Ca2+ required for contraction

Front 24

Cardiac muscle

Back 24

- striated
- involuntary
- innervated by autonomic nervous system
- 1-2 nuclei per cell
- Ca2+ for contraction
- myogenic activity (contract without nervous stimuli

Front 25

Smooth muscle

Back 25

- non-striated
- involuntary
- autonomic innervation
- one nucleus per cell
- Ca+ for contraction
- slower, sustained contractions
- inhibitory and excitatory synapses
- myogenic activity (contract without nervous stimuli)

Front 26

bone reformation

Back 26

inorganic ions are absorbed from the blood for use in bone formation

Front 27

bone resorption

Back 27

- bone degradation
- inorganic ions are released into the blood

Front 28

red muscle fibers

Back 28

- slow-twitch
- high myoblobin content
- lots of mitochondria

Front 29

white muscle fibers

Back 29

- fast-twitch muscle
- low myoglobin content
- less mitochondria
- anaerobic
- greater rate of contraction
- fatigue easily

Front 30

Bands that shorter during contraction

Back 30

H zone and I band

Front 31

Z line

Back 31

define boundaries of a single sarcomere

Front 32

M line

Back 32

- runs down center of sarcomere
- contains myosin

Front 33

I band

Back 33

thin filaments only

Front 34

A band

Back 34

spans entire length of thick filaments and overlapping protions of thin filaments

Front 35

troponin

Back 35

- Ca2+ binds troponin causing myosin-binding sites to be uncovered

Front 36

tropomyosin

Back 36

- rope-like
- associates with myosin fibrils
- blocks myosin-binding sites

Front 37

ATPase activity

Back 37

- resting stage: ATP is hydrolyzed
- Ca2+ binds to troponin and myosin binds to actin
- powerstroke: sarcomere contracts
- ADP + Pi are released
- New ATP binds to myosin, causing detachment of myosin from actin and relaxation

Front 38

all-or-none response

Back 38

- individual muslce fibers exhibit all-or-none response
- strenght of contraction of a single muscle fiber cannot be increased regardless of stimulus strength

Front 39

increasing strength of contraction

Back 39

- strength of contraction can increase only when the number of fibers involved increase

Front 40

tonus

Back 40

continula low-grade contractions of muscle (even at rest)

Front 41

simple twitch

Back 41

- the response of a single muscle fiber to a brief stimulus at or above threshold stimulus
- consists of a latent, contraction, and relaxation period

Front 42

latent period

Back 42

- time between stimulation and onset of contraction
- lag time in which action potential spreads along sarcolema and Ca2+ are released

Front 43

contraction period

Back 43

- muscles contract

Front 44

relaxation period

Back 44

- period of refraction (absolute and relative) in which the muscle is unresponsive or less response to a stilumus

Front 45

absolute refractory period

Back 45

- during relaxation period
- muscle is unresponsive to stimuli

Front 46

relative refractory period

Back 46

- during relaxation period
- takes a greater-than-normal stimulus to elicit another contraction

Front 47

summation

Back 47

- conbination of contractions in response to a frequent stimuli
- contraction becomes stronger and prolonged

Front 48

tetanus

Back 48

- stronger than a simple twitch
- contractions are continuous and muscle cannot relax
- eventual fatigue

Front 49

myogenic

Back 49

- when muscle contracts in the absence of nerve stimuli

Front 50

creatine phosphate

Back 50

- energy storage
- creatine phosphate + ADP = ATP + creatine
- creatine + ATP = creatine + ADP

Front 51

loose connective tissue

Back 51

- throughout body
- binds wpitehlium to underlying tissues
- packaging material
- holds organs in place

Front 52

3 proteinacious fibers in loose connective tissue

Back 52

collagenous fibers
elastic fivers
reticular fibers

Front 53

collagenous fibers

Back 53

- made of collagen
- give tensile strength

Front 54

elastic fibers

Back 54

- made of elastin
- give resilience

Front 55

reticular fibers

Back 55

- branched, tightly woven
- join connective tissue to adjoining tissue

Front 56

fibroblasts

Back 56

- secrete substances that are components of extracellular fibers
- cell found in connective tissue

Front 57

macrophages

Back 57

- engulf bacteria and dead cells
- cell found in connective tissue

Front 58

dense connective tissue

Back 58

- more collagenous fibers
- form tendons and ligaments

Front 59

tendons

Back 59

attach muscle to bone

Front 60

ligaments

Back 60

attach bone to bone

Front 61

origin

Back 61

location where end of muscle attaches to the stationary bone

Front 62

proximal end

Back 62

location of origin in limb muscles

Front 63

insertion

Back 63

end of muscle attached to the bone that moves during contraction

Front 64

distal end

Back 64

location of insertion in limb muscles

Front 65

synergistic muscles

Back 65

assiste the principal muscles during movement

Front 66

flexor muscles

Back 66

contract to decrease angle of a joint

Front 67

extensor muscles

Back 67

contract to straighten the joint

Front 68

abductor

Back 68

moves a part of the body away from body's midline

Front 69

adductor

Back 69

moves a part of the body toward the midline

Front 70

Contrast the means by which chondrocytes and osteocytes are nourished.

Back 70

- Chondrocytes are vascularized and are nourished via diffusion of nutrients from adjacent blood vessels
- osteocytes receive nutrients directly from circulatory system via Hacersian canals

Front 71

Two processes involved in bone formation. How do they differ?

Back 71

- endochondral ossification: cartilage is replaced by bone
- intramembranous ossification: mesenchymal cells are transformed into bone cells

Front 72

Which type of muscle has myogenic activity?

Back 72

smooth muscle and cardia muscle

Front 73

Periosteum

Back 73

- serves as the site of attachment of bone to muscle
- cells of periosteum differentiate into osteoblasts
- is a fibrous sheath that surrounds long bones