Ch. 6 key terms

Question 1

Parallel elastic component (PEC)

Answer 1

supplies resistance when a muscle is passively stretched; provided by the muscle membranes

Question 2

Series elastic component (SEC)

Answer 2

passive elastic property of muscle derived from the tendons

Question 3

contractile component

Answer 3

muscle property enabling tension development by stimulated muscle fibers

Question 4

active insufficiency

Answer 4

condition occurring when a joint muscle cannot shorten enough to cause full range of motion at both joints it crosses at the same time

Question 5

agonist

Answer 5

role played by a muscle acting to cause a movement

Question 6

antagonist

Answer 6

role played by a muscle acting to slow or stop a movement

Question 7

concentric

Answer 7

describing a contraction involving shortening of a muscle

Question 8

eccentric

Answer 8

describing a contraction involving lengthening of a muscle

Question 9

electromechanical delay

Answer 9

time between the arrival of a neural stimulus and tension development by the muscle

Question 10

fast-twitch fiber

Answer 10

a fiber that reaches peak tension relatively quickly

Question 11

isometric

Answer 11

describing a contraction involving no change in muscle length

Question 12

motor unit

Answer 12

a single motor neuron and all fibers it innervates

Question 13

myoelectric activity

Answer 13

electric current or voltage produced by a muscle developing tension

Question 14

neutralizer

Answer 14

role played by a muscle acting to eliminate an unwanted action produced by an agonist

Question 15

parallel fiber arrangement

Answer 15

pattern of fibers within a muscle in which the fibers are roughly parallel to the longitudinal axis of the muscle

Question 16

passive insufficiency

Answer 16

inability of a two-joint muscle to stretch enough to allow full range of motion at both joints at the same time

Question 17

pennate fiber arrangement

Answer 17

pattern of fibers within a muscle with short fibers attaching to one or more tendons

Question 18

slow-twitch fiber

Answer 18

a fiber that reaches peak tension relatively slowly

Question 19

stabilizer

Answer 19

role played by a muscle acting to stabilize a body part against some other force

Question 20

stretch-shortening cycle

Answer 20

eccentric contraction followed immediately by concentric contraction

Question 21

summation

Answer 21

building in an additive fashion

Question 22

tetanus

Answer 22

state of muscle producing sustained maximal tension resulting from repetitive stimulation

Question 23

transducers

Answer 23

devices that detect signals

Question 24

viscoelastic

Answer 24

having the ability to stretch or shorten over time