lecture 3 muscle

Question 1

muscles pull on bones to move the animal through space

Answer 1

locomotion

Question 2

muscles move the jaw as part of oral processing of food

Answer 2

mastication

Question 3

three type of muscle

Answer 3

skeletal
smooth
cardiac

Question 4

describe skeletal muscle

Answer 4

attached to bone, moves skeleton

locomotion, respiration, generates heat by shivering

multinucleated
somatic innervation (voluntary)

Question 5

describe smooth muscle

Answer 5

GI tract and other organs, skin and most vessels

• moved ingesta, gland products and blood

Question 6

Describe Cardiac Muscle

Answer 6

heart and great vessels

pumps arterial blood
striated
branched cells
innervated by ANS (involuntary)
Purkinje fibers corrdinate heartbeat

Question 7

the force a muscle produces is related to the number of ___ active

Answer 7

muscle fibers

more active fibers = more force

Question 8

muscles can only ___

Answer 8

pull

Question 9

skeletal muscle cells are made up of bundle of ___

Answer 9

myofibrils

Question 10

myofibrils are made of ___ and ___ in units called ____

Answer 10

thin (actin)
thick (myosin)

sarcomeres

Question 11

when muscle contract ___ and ___ get closer together

Answer 11

myosin and actin

Question 12

types of muscle fatigue

Answer 12

slow fatigue resistance
fast fatigue resistant
fast fatigue

(fast intermediate

Question 13

example of slow fatigue resistant

Answer 13

migratory bird

slow contraction

• weak forces
• high resistance to fatigue
• maintain activity for long periods
• high oxidative enzyme, low glycoltic and ATPase

Question 14

explain fast fatigue resistant

Answer 14

antelope running

fast contraction
force maintained over time
animal active for long periods

high oxidative and glycolytic capacity

Question 15

explain fast fatigue

Answer 15

cheetah running

fast contraction
large forces, few contractions then needs rest
- high glycolytic activity and ATPase, low oxidative capacity

Question 16

describe fast intermediate

Answer 16

catch all

• fast contraction but can maintain (some but not all) for an extended period
• fatigue resistance- varies between species

Question 17

three type of contraction of muscle

Answer 17

concentric
eccentric
isometric

Question 18

describe concentric contraction

Answer 18

shortens
load < muscle capacity
(bicep curl)

Question 19

describe eccentric contraction

Answer 19

actively lengthens
load > capacity
- resists but lengthens
(lowering patient gently to floor)

Question 20

describe isometric contraction

Answer 20

length remains constant
-angle unchanged
(carrying heavy box)

Question 21

describe passive stretch

Answer 21

antagonist muscle working will pull (lengthen other muscle)

touch your toes

Question 22

type of muscle fibers arrangments

Answer 22

strap
fusiform
pennate
circular

Question 23

strap muscles

Answer 23

parallel fibers

Question 24

fusiform muscles

Answer 24

converge at ends
(football shaped)
biceps

Question 25

pennate muscles

Answer 25

fibers lie at angle to muscle axis = more strength unipennate- one tendon bipennate- 2 tendons multipennate- multiple internal tendons

Question 26

___ cross section is perpendicular to muscle axis

Answer 26

anatomical muscle axis (line from one end of muscle to the other- connects the two ends)

Question 27

___ cross section is perpendicular to muscle fibers

Answer 27

physiologic

Question 28

increasing the cross section between anatomical and physiologic will ___ force

Answer 28

angle between muscle axis and muscle fibers increase force= bigger angle

Question 29

muscle fibers are surrounded by ___

Answer 29

endomysium

Question 30

groups of muscles are called ___ and are surrounded by ____

Answer 30

fascicles (fasciculi) | perimysium

Question 31

whole muscle is surrounded by ___

Answer 31

epimysium

Question 32

connective tissue of muscles from outside to inside

Answer 32

epimysium (around whole muscle) perimysium (around fascicle) endomysium (around muscle fiber)

Question 33

narrow cordlike connection between muscles and bones

Answer 33

tendon

Question 34

flat sheet like connection of muscles

Answer 34

aponeurosis

Question 35

connection of muscle attachments where the connective tissue can not be seen by the naked eye

Answer 35

fleshy attachment

Question 36

end of muscle that is more fixed or proximal

Answer 36

origin

Question 37

end of muscle that is more mobile or more distal

Answer 37

insertion

Question 38

tendons heal slowly because

Answer 38

they are poorly vascularized

Question 39

motor unit

Answer 39

motor axon to muscle fibers | 5-2000 muscle fibers per motor unit

Question 40

sensory innervation of muscles

Answer 40

stretch receptors, tendon organs, pain receptors (in muscle and tendons)

Question 41

___ help prevent friction and wear when pressure is applied from one side

Answer 41

bursa outside of joint capsule (its own thing) muscle and other tissue- bursa are not found bone to bone

Question 42

when pressure is applied to more than one side (bone below and CT above ___ are formed

Answer 42

tendon sheaths - form around tendons - has little hole to allow innervation (mesotendon) - example (retinaculum (CT) then tendon wrapped in tendon sheath then bone)

Question 43

hole in tendon sheath to allow innervation and blood supply

Answer 43

mesotendon

Question 44

skeleton is a system of ___ and levers. Muscles act on it to produce ____

Answer 44

supports movement

Question 45

___ support is support without muscular effort

Answer 45

static support connective tissue (stay mechanism)

Question 46

first order lever

Answer 46

head and spine seasaw head resistance down, fulcrum (spine in middle) muscle pulls down to keep head elevated fulcrum between ends. resistance at one end. input force applied at other end of lever

Question 47

second order levers

Answer 47

calcaneus and gastrocnemius fulcrum (foot) resistance from weight of animal pulls down gastrocnemius pulls up fulcrum at one end force applied to other end load is between input force and fulcrum

Question 48

third order lever

Answer 48

elbow and bicep resistance of weight of arm pulls down - muscle pulls up (force) - fulcrum (elbow) fulcrum at one end load is at other end force applied between load and fulcrum

Question 49

in 1st order levers longer input levers =

Answer 49

more power to move load output/input <1 (1st order fulcrum in between load and resistance)

Question 50

in 1st order levers longer output lever=____

Answer 50

longer output lever= load moves farther/time output/input > 1

Question 51

armadillo lower output/input ration =

Answer 51

slower but more powerful motion of paw (digging)

Question 52

kangaroo higher output/input ratio =

Answer 52

faster but less powerful motion of foot (hopping)

Question 53

muscle that contracts to cause a motion

Answer 53

agonist/ prime mover

Question 54

muscle that resists the motion of the agonist

Answer 54

antagonist - muscles move opposite biceps and triceps (one relaxed one active)

Question 55

if antagonist muscles both contract the joint is ___

Answer 55

stabilized in fix position

Question 56

muscle that helps move a joint

Answer 56

helper muscle (synergist) biceps and brachialis

Question 57

muscle fibers can shorten to ___ of their resting length

Answer 57

1/3

Question 58

stretch or tear ligaments

Answer 58

sprains

Question 59

bruise deep tissue without tearing the skin

Answer 59

contusions

Question 60

inflammation/irritation of tendon of tendon sheath

Answer 60

tendinitis

Question 61

inflammation of bursa

Answer 61

bursistis

Question 62

mild injuries damage ___ % of muscle fibers and have ___ recovers

Answer 62

5 | quick

Question 63

Moderate injuries damage ___ muscle fibers and take ___ to heal

Answer 63

most | months