Week 2/3

Question 1

Skeletal muscles functions

Answer 1

movement
protection
posture and support
body heat
-by contraction and shivering

Question 2

Aggregate muscle action

Answer 2

muscles work in groups rather than independently to achieve a given joint motion

Question 3

Skeletal muscles

Answer 3

over 600
aprx. 40-50% body weight
215 pairs usually work in cooperation with each other to perform opposite actions at the joints which they cross

Question 4

Skeletal muscle structure

Answer 4

hexagonal array of myosin (thick) and actin (thin) filaments

arranged along the actin filament are the regulatory proteins troponin and tropomyosin

Question 5

Regulatory proteins

Answer 5

troponin

tropomyosin

Question 6

Parallel muscle shape and fiber arrangement

Answer 6

great range of motion
not great force production
parallel to length of muscle
flat, fusiform, strap, radiate, sphincter, circular

biceps

Question 7

Pennate muscle shape and fiber arrangement

Answer 7

oblique to the tendons
unipennate, bipennate, multipennate

triceps

Question 8

Shape and fiber arrangement affects

Answer 8

force production

ROM

Question 9

4 properties related to fore production and movement about joints

Answer 9

irritability or excitability
contractility
extensibility
elasticity

Question 10

Irritability or excitability

Answer 10

property of muscle being sensitive or responsive to chemical, electrical, or mechanical stimuli

Question 11

Contractility

Answer 11

ability of muscle to contract and develop tension or internal fore against resistance when stimulated

Question 12

Extensibility

Answer 12

ability of muscle to be passively stretched beyond its normal resting length

Question 13

Elasticity

Answer 13

ability of muscle to return to its original length following stretching

Question 14

Intrinsic

Answer 14

originate and insert in the same region

Question 15

Extrinsic

Answer 15

oringinate in one region and insert into another

Question 16

Action

Answer 16

contractions: isometric, isotonic, isokinetic, concentric, eccentric

Question 17

Isometric

Answer 17

producing force but not shortening the muscle

tension is developed within the muscle but joint angles remain constant
static contractions
resists external forces at a joint

Question 18

Isotonic

Answer 18

same tension within the muscle

Question 19

Isokinetic

Answer 19

same speed within the muscle

Question 20

Concentric

Answer 20

muscle developing tension as it shortens

Question 21

Eccentric

Answer 21

muscle lengthening under tension

Question 22

Innervation

Answer 22

the nerve supply

Question 23

Amplitude

Answer 23

level/strength of signal sent by the nerve

Question 24

Gaster

Answer 24

center/belly of the muscle

a muscle will contract toward the gaster

Question 25

Connective tissue that runs through the muscle

Answer 25

Aponeurosis

Fascia

Question 26

Origin

Answer 26

the more stable side of the muscle

Question 27

Insertion

Answer 27

less stable side of the muscle

Question 28

Passive ROM at a joint

Answer 28

an external force could be providing the movement

dependent on joint design

Question 29

Active ROM at a joint

Answer 29

contract the muscle and produce the movement yourself

deoendent on
muscle architecture (parallel and pennate)
moment arm (insertion point measured past the respective joint)
fiber length

Question 30

Moment arm of muscle

Answer 30

distance from the center of rotation to the insertion point