chapter 9 muscular system I Flashcards Preview

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Flashcards in chapter 9 muscular system I Deck (59):
1

functions of muscular system?

produce movement
maintain posture
stabilize joints
generate heat

2

why do muscles generate heat?

use cellular aerobic respiration, lose some energy as heat

3

functional characteristics of muscle system

excitability/irritability
contractility
extensibility
elasticity

4

contractibility

shortened when stimulated

5

extensibility

stretch 3x original length
uterus

6

elasticity

recoils to original length

7

skeletal control

voluntary/conscious
controlled by nervous system

8

cardiac control

involuntary control by endocrine and ANS

9

smooth control

involuntary control by endocrine and ANS

10

muscle fibers

muscle cells

11

what surrounds muscle fibers?

connective tissue

12

endomysium

around a single muscle fiber

13

perimysium

around a fasicle (bundle) of fibers

14

epimysium

covers entire skeletal muscle

15

fascia

on the outside of the epimysium, surround muscle as a whole

16

flesh eating bacteria

necrotizing fasciitis

17

how do u get necrotizing fascia?

from major trauma, attacks soft tissue fascia

18

what are treatments for necrotizing fascia?

antibiotics
amputation
tissue graft

19

what does each muscle have?

nerve
artery
vein

20

ways that muscles attach

direct
indirect

21

indirect attachment

tendon (cord)
aponeurosis
white cuz of collagen

22

aponeurosis

flat tendonous tissue

23

why are the tendon and aponeurosis white?

collagen fibers

24

attachment sites

origin
insertion

25

origin attachment site

more stable, proximal

26

insertion attachment site

more movable
distal to origin in limbs

27

muscle fiber cell structures

sarcolemma
sarcoplasm
myofibrils
sarcomere
sarcoplasmic reticulum

28

sarcolemma

husk
membrane of muscle fiber

29

muscular dystrophy (duchenne's)

inherited x-linked recessive
muscle fibers atrophy; shrinks, weakening
death around 20
weakened sarcolemma

30

sarcoplasm

glycosomes
myoglobin

31

what do glycosomes store?

glycogen

32

what is purpose of glycosomes?

to break down to glucose to feed CAR

33

purpose of myoglobin?

store O2

34

myofibrils

muscle protein filaments
rod like structures made up of myosin & actin filaments; protein

35

myofibrils at rest give what?

distinct striations (bands)
I band
A band

36

I band

light band

37

A band

dark band

38

what is sarcomere and what makes it up?

z-disc to z-disc
contractile unit of muscle
thick filaments - myosin
thin filaments - actin
bare zone
z disc

39

thick filaments

myosin

40

thin filaments

actin

41

purpose of mysoin filaments

ATPase enzymes
large head groups link thick and thin filaments during contraction

42

bare zone

lakcs actin filaments at rest

43

sarcoplasmic reticulum (SR)

specialized SER
stores Ca2+ for muscle contraction

44

what do muscles do when they contract?

pull on structures they are attached to (trochanter, tubercle, tuberosity, etc.)

45

action

movements accomplished when it contracts (ex. flexion, extension)

46

interactions

working together to bring about a desired movement

47

functional groups

prime mover
antagonist
synergist

48

prime mover

primarily responsible for desired movement
ex. brachialis

49

antagonist

opposes the prime mover
ex. triceps

50

synergist

aids the prime mover by either:
adding extra force
preventing or reducing undesirable movements
ex. biceps

51

naming skeletal muscle

location
shape
relative size
direction of fibers or fascicles (orientation)
location of attachment (origin first)
number of heads
action

52

ex of location

tibialis anterior

53

ex of shape

deltoid, trapezius

54

ex of relative size

ending with maximus, minimus, longus, brevi

55

ex of orientation

rectus abdominis

56

ex of location of attachment

sternocleidomastoid

57

ex of number of head

prefix of bi, tri, or quad

58

ex of action

extensor, flexor,... extensor digitorum

59

im injection site

deltoid
vastus lateralis