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Chapter 6 Muscle
Question | Answer |
---|---|
What are the four major functional characteristics of skeletal muscles? | Contractility, Excitability, Extensibility, and Elasticity |
The ability of skeletal muscles to shorten with force | contractility |
responds to stimulus | excitability |
outermost connective tissue | extensiblity |
inside the fascia, second layer of connective tissue | fascia |
bundle of muscle cells | epimysium |
surrounds each fascicle | muscle fasicle |
thin myofiliaments, peals | actin myofilaments |
thick myofiliaments, golf clubs | myosin myofilaments |
basic unit of muscle | sarcomeres |
thin line of actin, starts and finishes sacomeres | z line |
on both sides of z line, light area, actin | l band |
dark area of sarcomere, myosin | a band |
between a zones, myosin | H zone |
raises the eyebrow | occipitofrontalis |
closes the eyelids | orbicularis oculi |
puckers the lips | orbiculais oris |
flattens the cheeks | buccinator |
smiling | zygomaticus |
sneering | levator labii superioris |
frowning | depressor anguli oris |
chewing | mastication |
2 pairs of pterygoids, temporalis, and masseter | mastication muscles |
change the shape of the tongue | instrinic muscles |
moves the tongue | extrinic muscles |
rotates and abducts head, prime mover | sternocleidomastoid |
group of muscles that keep the back straight and the body erect | erector spinae |
accomplishes quiet breathing | diaphragm |
rotates scapula | trapezius |
pulls the scapula anteriorly | serratus anteriorly |
abducts and flexes the arm | pectoralis major |
extends arm powerfully, rotates, and adducts the arms | latissimus dorsi |
attaches the humerus to the scapula and clavicle | deltoid |
extends the forearms | triceps brachii |
flexes the forearm | biceps brachii |
flexes and supinates the forearm | brachialis |
flexes the wrist | flexor carpi |
extends the wrists | extensor carpi |
flexes the fingers | flexor digitorum |
extends the fingers | extensor digitorum |
buttocks | gluteus maximus |
hip muscles | gluteus medius |
extends the legs, anterior thigh muscle | quadriceps femoris |
flexes the thigh | sartorius |
posterior thigh muscle, flexes the legs and extends the thigh | hamstring |
dark line down the center, myosin | M line |
nerve cells that carry action potential to muscle | motor neurons |
each branch of an axon that connects to the muscle | neuromuscular junction/ synapse |
enlarged nerve terminal | presynaptic terminal |
space between presynaptic and the muscle | synaptic vesicles |
the muscle fiber touching the synaptic cleft | acetylcholine |
secrete neurotransmitters | acetylcholinesterase |
neurotransmitters from the synaptic vesicle | acetylcholine |
makes sure that only one action potential is sent to the motor neuron | acetylcholinesterase |
sliding of actin and myosin during contraction | sliding filament mechanism |
contraction of an entire muscle responding to stimulus that causes the action potential in one or more muscle fibers | muscle twitch |
muscle fiber will not respond until the stimulus | threshold |
the time between application of stimulus and the beginning of contraction | lag phase |
ATP | energy needed for muscle contraction |
increase in number of motor units being activated | recruitment |
center | light area in the H zone |
H zone | only myosin |
outside cell membrane | positively charged |
inside cell membrane | negatively charged |
resting membrane potential | charge difference |
action potential | the reversal back for the charge |
motor neurons | nerve cells carry action to muscle fibers |
synapse | center of the cell |
neuron muscular junction | branch that connects to the muscle |
postsynaptic terminal | enlarged nerve terminal |
synaptic vessels | each presynaptic terminal |
actin and myosin myofilaments | 2 kinds of protein fibers |
synaptic cleft | spaces between presynaptic and muscle cell |
True | True or false: you have to have ATP for a muscle to contract |
False | True or false: There is 3 different types of protein fibers |