Classification SK MM

Question 1

agonists

Answer 1

prime movers, produce particular movement

Question 2

antagonists

Answer 2

oppose or reverse a movement. can be a primer (bicep muscle of arm that is prime mover of elbow flexion is antagonized by tricepts a primse movement of elbow extension)

Question 3

synergists

Answer 3

aid the action of agonists either by assisting with the same movement or by reducing undesirable/unnecessary movement. ex: can make fist without bending wrist bc syn mm stabilize wrist joints and allow the prime mover to exert its force at finger joints

Question 4

fixators

Answer 4

specialized syngergists immobilize the origin of prime mover so that all the tension is exerted at the insertion. ex: muscles that help maintain posture, or muscles that stabilize scapula during arm movements

Question 5

origin

Answer 5

attachment of mm to immovable or less movable bone

when mm contracts, it mvoes toward the origin

Question 6

insertion

Answer 6

attachment to the movable bone

Question 7

parallel muscles

Answer 7

long, run parallel along the axis

ex: sartorius (inner thigh), rectis abdominis

Question 8

convergent muscles

Answer 8

fascicles converge toward a single insetion tendon

ex: pec muscle

Question 9

circular muscle

Answer 9

others like a sphincter (squeexer)

ex: mouth

Question 10

fusiform muscle

Answer 10

modification fo parallel, springle shaped with expanded belly

ex: bicepts brachii

Question 11

pennate muscles

Answer 11

feather like

short fascicles attach obliquely to central tendon

unipennate: fascicles run to 1 side (flexor pollicus longus)
bipennate: “ on both sides (rectus femoris)
multipennate: “ from several different sides(deltoid)

Question 12

naming mm

Answer 12

1. direction ( imaginary line); rectus vs oblique
2. size (maximus, minimus, longus)
3. location (bone, temporalis mm)
4. # of origins (bicept, tricepts, quadriceps)
5. attachment sites
6. shape (distinct shape, deltoid, thomboid)
7. action (flexor, extensor adductor)

Question 13

isotonic contraction

Answer 13

movement does take place, bc tension generated by the contracting muscle exceeds the load on the muscle, occurs when you use your muscles to push/pull an object

Question 14

concentric contraction

Answer 14

muscle decreases in length against an opposing load, such as lifting a weight up

Question 15

eccentric contraction

Answer 15

muscle increases in length as it resists a load, such as loweriing a weight down in a slow, controlled fashion

• during concentri : muscles shortening serve as agonists. during eccentri: muscles lengthening serve as agonists ( and do al of works)