lecture 11

Question 1

functions of the muscular system

Answer 1

supporting body movement
generating heat

Question 2

origin

Answer 2

end of muscle attached to stabilized or stationary bone

usually proximal

Question 3

insertion

Answer 3

end of muscle attached to moving bone

usually distal

Question 4

muscle belly

Answer 4

thickened portion of the muscle between tendons

Question 5

muscle actions

Answer 5

movements that are possible when the muscle contracts

Question 6

Reverse muscle actions (RMAs)

Answer 6

result when the origin and insertion are reversed

NOT when the muscle relaxes

most muscles do not have RMAs

Question 7

lever

Answer 7

an object that moves around a fulcrum

Question 8

load

Answer 8

resistance against effort

Question 9

effort

Answer 9

force required to move a load

Question 10

first class levers

Answer 10

fulcrum is between effort and load
- like a see saw
eg. looking up
- posterior neck muscles (effort) contract to lift the head(load) at the atlanto-occipital joint (fulcrum)

Question 11

second class lever

Answer 11

load is between effort and fulcrum
- like a wheelbarrow
eg. gastrocnemius (effort) lifts the body weight (load) at the toes (fulcrum)

Question 12

third class levers

Answer 12

effort between fulcrum and load
most common in the body
eg. biceps (effort) life the hand (load) at the elbow joint (fulcrum)

Question 13

why use third class levers if second class produced an advantage?

Answer 13

third class levers allow faster movement, but take more effort

Question 14

muscles usually work in ______

Answer 14

opposing pairs
eg. biceps and triceps brachii

Question 15

agonist

Answer 15

muscle that exerts effort to move lever

Question 16

antagonist

Answer 16

muscle that opposes the agonist

must relax for the agonist to move

Question 17

synergists

Answer 17

muscles that stabilize intermediate. joints when contracted

hold other joints stable while one moves

Question 18

fixators

Answer 18

muscles that stabilize one end of bone so that the other can move

eg. muscles that stabilize the scapula during abduction of the arm (trapezius, serratus anterior, etc)

Question 19

compartments

Answer 19

groups of skeletal muscles, their nerves, and blood vessels
- have specific functions

eg. flexor compartments of upper limb are the anterior sets of muscles

Question 20

muscle function vs action

Answer 20

action - movement
function - what they do

eg. action - contract to close the mandibe

function - to chew

Question 21

functions of the facial muscles (general)

Answer 21

to express emotions
- speech / vocalization

Question 22

orbicularis oculi action

Answer 22

closes the eyelids

Question 23

orbicularis oris action

Answer 23

close the lips / purses the lips (duckface)

Question 24

occipitofronalis actions

Answer 24

frontal - raise eyebrows wrinkle forehead

occipital - raise hair (pulls on scalp)

Question 25

epicranial aponeurosis

Answer 25

aponeurosis that connects the frontal and occipital bellies of the occipitofrontalis

Question 26

aponeurosis

Answer 26

sheet like tendons

Question 27

platysma action

Answer 27

pulls corners of mouth laterally and inferiorly depresses mandible

Question 28

masseter / temporalis actions

Answer 28

elevate the mandible

Question 29

sternocleidomastoid actions

Answer 29

rotate the head extend the head at atlanto-occipital joint has RMA (elevation of sternum)

Question 30

what happens if you only contract one sternocleidomastoid?

Answer 30

the head will rotate

Question 31

function of abdomen muscles

Answer 31

protect abdominal viscera move vertebral column

Question 32

why do all the abdominal muscle fascicles run different ways

Answer 32

mainly stabilization, protection as well

Question 33

tendinous intersections of rectus abdominis connection tissu

Answer 33

fibrous

Question 34

The rectus abdominis originates at the pubic symphysis and inserts on the costal cartilages. If RMA of this muscle were possible, what movement would be permitted?

Answer 34

flexion of the vertebral column

Question 35

a muscle cannot move a bone to which it is not ____

Answer 35

attached

Question 36

central tendon

Answer 36

aponeurosis where the diaphragm inserts

Question 37

serratus anterior action

Answer 37

abducts the scapula assists in pushing

Question 38

trapezius permits:

Answer 38

rotation, adduction, depression, stabilization of the scapula

Question 39

pectoralis major permits:

Answer 39

adduction, medial rotation, flexion or the arm

Question 40

deltoid permits:

Answer 40

abduction, medial/lateral rotation, flexion/extension of the arm

Question 41

latissimus dorsi permits

Answer 41

extension, adduction, medial rotation of the arm

Question 42

latissimus dorsi RMA

Answer 42

elevation of the vertebral column and torso

Question 43

biceps brachii permits

Answer 43

flexion of the arm at the elbow joint supination of the hand

Question 44

triceps brachii permits

Answer 44

extension of the forearm at the elbow joint

Question 45

brachioradialis function

Answer 45

controls speed of movement of the arm

Question 46

brachioradialis permits

Answer 46

supination and pronation of the hand

Question 47

gluteus maximus permits

Answer 47

flexion of the leg at the hip joint lateral rotation of the femur at hip

Question 48

gluteus maximus RMA

Answer 48

extension of the torso

Question 49

gluteus medius permits

Answer 49

abduction and medial rotation of the femur

Question 50

flexor compartment of the thigh permits

Answer 50

flexion of the lower limb at the knee joint extension of the leg at the hip joint

Question 51

extensor compartment of the thigh permits

Answer 51

extension of the lower limb at the knee joint flexion of the leg at the hip joint

Question 52

all three "vastus" heads of the quadriceps originate on the ____

Answer 52

femur

Question 53

gracilis permits

Answer 53

adduction of the thigh at the hip joint medial rotation of the thigh

Question 54

soleus permis

Answer 54

plantar flexion of the foot at the ankle joint

Question 55

gastrocnemius permits

Answer 55

plantar flexion of the foot at the ankle flexion of the lower limb at the knee

Question 56

tibialis anterior permits

Answer 56

dorsiflexion of the foot at the ankle inversion of the foot at the intertarsal joints

Question 57

ways to prevent muscle injuries

Answer 57

regular, moderate exercise stretching nutrition sleep

Question 58

spasm

Answer 58

involuntary contraction of a muscle or muscle group when painful - called cramps

Question 59

main and other cause of spasms/cramps

Answer 59

dehydration injury, overuse, prolonged periods in one position, inadequate bloodflow

Question 60

muscle soreness

Answer 60

due to microscopic damage to muscles (torn sarcolemmas, etc) may be delayed

Question 61

PRICE

Answer 61

Protection, rest, ice, compression, elevation remedy for minor injuries

Question 62

plantar fasciitis

Answer 62

chronic inflammation of the plantar aponeurosis causes:excess weight, ill fitting shoes treatments: PRICE, stretching, orthotics, surgery, weight loss

Question 63

compartment syndrome

Answer 63

excess fluid causing swelling in the fascia causes: pressure that restricts blood flow to a compartment treatments: fasciotomy is severe

Question 64

3 facts about muscles

Answer 64

they work in groups theres organized in compartments their structure determines their function