Studied by 1 person
myology
study of muscle
What are the functions of muscle tissue?
body movement
stabilizing body positions
regulate organ volume
generate heat
What are the three types of muscle tissue?
skeletal, smooth, cardiac
Describe skeletal muscle tissue. Striated or nonstriated? Voluntary or involuntary? Where is it located?
-striations
-voluntary
-attached to and moves bones
Describe smooth muscle tissue. Striated or nonstriated? Voluntary or involuntary? Where is it located?
-nonstriated
-involuntary
-around organs that need to squeeze
Describe cardiac muscle tissue. Striated or nonstriated? Voluntary or involuntary? Where is it located?
-striated
-involuntary
-heart
Draw a relaxed and contracted sarcomere and label the myosin, actin, and cross bridge, and z-line.
(make sure your drawing and labels matches this picture)
What is a sarcomere?
functional unit of muscle
What is a muscle fiber?
muscle cell
Describe how muscle contraction occurs.
stimulus arrives at neuromuscular junction
acetylcholine released
calcium released
ATP released
cross bridges on myosin release from actin
myosin pulled down actin by cross bridges
z-lines pulled closer together
sarcomere contracted → myofibril contracted → muscle fiber (cell) contracted → muscle fiber bundle contracted → whole muscle contracted
How does skeletal muscle produce body motion?
-muscles exert force on tendons which pull on bones
-bones act as levers (rigid rod) and joint act as fulcrums (fixed point or pivot point)
-motion is achieved when the effort (muscle contraction) is greater than the resistance (weight of part being moved) M=E>R
Draw the muscle parts and label the origin, belly, and insertion.
(make sure your drawing and labels matches this picture)
What is the origin of a muscle?
attachment of muscle tendon to stationary bone
What is the belly of a muscle?
fleshy part between origin and insertion
What is the insertion of a muscle?
attachment of a muscle tendon to the moving bone
What does high strength mean?
low range of motion (ROM)
What does low strength mean?
high range of motion (ROM)
What is the prime mover?
muscle causing desired movement
What is the antagonist?
opposite action to prime mover
What is the synergist?
muscles that help steady movement
What does rectus mean?
fibers run parallel to midline
What does transverse mean?
fibers run perpendicular to midline
What does oblique mean?
fibers run at an angle to midline
What does location have to do with muscle names?
sometimes muscles named for a structure near where they are found in the body
What does maximus mean?
largest of muscle group
What does minimus mean?
smallest of muscle group
What does longus mean?
longest of muscle group
What does brevis mean?
shortest of muscle group
How many origins does a bicep have?
two
How many origins does a tricep have?
three
How many origins does a “quadricep” have? (group of muscles)
four
What shape is a deltoid?
triangle
What shape is a trapezius?
trapezoid
What shape is a rhomboideus?
rhomboid
What does a flexor do?
decrease the angle of the joint
What does an extensor do?
increase the angle of the joint
What does an abductor do?
move away from midline
What does an adductor do?
move toward midline
What does a levator do?
lifts body part
What does a depressor do?
lowers body part
What does a supinator do?
turns palm upward
What does a pronator do?
turns palm downward
What does a tensor do?
makes body part rigid/tight to stabilize position
What does a sphincter do?
muscle that encloses an opening
What is fascia?
white connective tissue binding muscle together
Describe thumb movements.
most dexterous in terms of muscle movement
Name the different types of thumb movements.
-flexion
-extension
-abduction
-adduction
-circumduction
-opposition
What is opposition?
-thumb can touch each finger tip
-most important movement
Note
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