Muscles

Question 1

what is sarcolemma

Answer 1

outer cell membrane on striated muscle fibers

Question 2

what are the functions of the sarcolemma

Answer 2

excitable membrane, can pass an electrical current, and acts as a barrier

Question 3

do skeletal muscle cells have multiple nuclei

Answer 3

yes, one is not enough, they are too long

Question 4

what is muscle tone

Answer 4

(readiness to fire) the continuous and passive partial contraction of the muscles, or the muscle’s resistance to passive stretch during resting state

Question 5

where do you want your muscles to be at on the muscle tone scale

Answer 5

just below firing threshold (fibers will be slightly firing)

Question 6

when does a spasm or twitch occur

Answer 6

when the muscle tone is too high or there is too much stimulation

Question 7

what happens to muscle tone during REM sleep

Answer 7

the tone shuts down or decreases

Question 8

why do our muscles act as a smooth movement

Answer 8

because the muscles are continuously and steadily contracting/firing as it is being used

Question 9

what is a myofilament

Answer 9

actin and myosin stacked end to end, a protein filament that makes up a myofibril

Question 10

what makes up a myofibril

Answer 10

myofilaments: actin and myosin, longitudinal fibril

Question 11

what makes up a muscle cell

Answer 11

myofibrils; cells that make up muscle tissue

Question 12

how does a muscle grow

Answer 12

most of the time the muscle cells get larger (myofilaments get bigger) through exercise

Question 13

what does new research suggest for how muscle cells grow

Answer 13

through satellite stem cells

Question 14

if you cut through a muscle, will it regenerate

Answer 14

yes, to a certain extent

Question 15

what is a sarcomere

Answer 15

a minimal contractile or functional unit (basic unit), actin -thin filament and myosin- thick filament as “parts”, stack these on end to make a myofilament

Question 16

what is sarcoplasmic reticulum

Answer 16

surrounds the myofibrils; an exchange or turnover system of oxygen and fuel, stores and releases calcium ions during muscle contraction and absorb them during relaxation

Question 17

what is the true measure of physical fitness

Answer 17

speed of recovery and the VO2 max

Question 18

what is endomysium

Answer 18

a thin layer of connective tissue around each muscle cell/fiber, separates the muscle fibers in a fascicle

Question 19

what is a fascicle

Answer 19

bundle of muscle fibers wrapped by perimysium

Question 20

what is a “muscle”

Answer 20

a bundle of fascicles surrounded by epimysium

Question 21

what is epimysium

Answer 21

dense irregular connective tissue that surrounds the whole muscle

Question 22

what do you have left if you take away all the muscle fibers (cells)

Answer 22

a connective harness (3 layers of “mysiums”: endo, epi, peri)

Question 23

what happens when you “pull” a muscle

Answer 23

you are either tearing the connective harness or tendon

Question 24

what are the 4 types of muscle

Answer 24

circular, convergent, parallel, and pennate (bipennate or unipennate)

Question 25

what is a circular muscle

Answer 25

a sphincteral muscle, surrounds a body opening

Question 26

what is a convergent muscle

Answer 26

(pectoralis major) "fan shaped" arises from a broad area and converges to a single tendon

Question 27

what is a parallel muscle

Answer 27

(biceps brachii) "tubular or cigar shaped" forces are parallel

Question 28

what is an example of a bipennate muscle

Answer 28

rectus femoris

Question 29

what is an example of a unipennate muscle

Answer 29

extensor digitorium longus

Question 30

what is a pennate muscle

Answer 30

feather like, distribute the load, high efficiency, tend to be type I

Question 31

what are the 2 muscle roles

Answer 31

stabilizing and mobilizing

Question 32

what muscle role is a type I muscle

Answer 32

stabilizing

Question 33

what muscle role is a type II muscle

Answer 33

mobilizing

Question 34

what type of muscle is the red-slow fiber

Answer 34

Type I

Question 35

what type of muscle is the white-fast fiber

Answer 35

Type II

Question 36

what are the characteristics of a Type I fiber

Answer 36

deep, postural or anti-gravity, high endurance, crosses one joint, oxidative

Question 37

what are the characteristics of a Type II fiber

Answer 37

low endurance, inefficient, superficial muscle, crosses 2 joints, glycolytic (anaerobic)

Question 38

what is smooth muscle

Answer 38

unstriated, spindle-shaped, randomly arranged, involuntary, autonomic, visceral muscle, slow contraction

Question 39

what is cardiac muscle

Answer 39

striated, involuntary visceral muscle (walls of heart and adjacent parts of the vessels) autonomic, held together by discs

Question 40

what is atrial fibrillation

Answer 40

loses the "beat" or rhythm of the cardiac muscle, the heart can stop suddenly

Question 41

what is the origin of a muscle

Answer 41

a fixed point where the muscle attaches to bone

Question 42

what is the insertion of a muscle

Answer 42

the more distal point, end that tends to move

Question 43

what are the 4 types of muscle action

Answer 43

agonist, antagonist, synergist, and stabilizer

Question 44

what is an agonist muscle

Answer 44

the prime mover, causes specific movement through its own contraction

Question 45

what is an antagonist muscle

Answer 45

it opposes the agonist, returns the limb to its initial position

Question 46

what is a synergist muscle

Answer 46

assists, supports, or helps perform the same set of joint motion as the agonist "neutralizer"

Question 47

what is a stabilizer muscle

Answer 47

supports joints at rest or during other movements (postural muscles)

Question 48

what is a neuromuscular junction

Answer 48

connects the nervous system to the muscular system via synapses

Question 49

what is the neurotransmitter that activates the neuromuscular junction

Answer 49

acetylcholine

Question 50

what happens with myasthenia gravis

Answer 50

you first get neuromuscluar weakness first in the eyelid (ptosis) then speaking, then swallowing

Question 51

what is the standard way to describe muscles and their function

Answer 51

OINA

Question 52

what is muscle action

Answer 52

named for the joint where the action is of the affected muscles

Question 53

what does smooth muscle (not jerky) action rely on

Answer 53

all 4 actions to happen at once (agonist, antagonist, synergist, and stabilizer)

Question 54

what are you testing when you check reflexes

Answer 54

the connections to the spinal cord and that the muscles are all working together like they should

Question 55

where in the brain are muscle movements controlled/coordinated

Answer 55

the cerebellum

Question 56

what is an ataxia

Answer 56

a neurological sign consisting of lack of voluntary coordination of muscle movements

Question 57

what happens when two cardiac muscle touch each other

Answer 57

they start beating together

Question 58

If someone is paralyzed from the neck down, do they still have reflexes

Answer 58

yes they still work, they are hyper-reflexive (even stronger than before) muscle tone is set too high

Question 59

what happens if you cut a nerve i.e. the femoral nerve

Answer 59

you wouldn't have reflexes anymore

Question 60

what are the 3 layers of connective tissue in a skeletal muscle

Answer 60

epimysium, perimysium, and endomysium