Week 2 Flashcards
Muscles have different
shapes and fiber arrangements
Cross section diameter
The bigger the diameter = greater force exertion
Longer muscles can…
shorten through a greater range
2 major fiber arrangements
Parallel and Pennate
Describe Parallel muscles
fibers arranged parallel to muscle
Have a greater range of movement than pennate arrangements
Parallel Muscle Categorize
Flat Fusiform Strap Radiate Sphincter or Circular
Pennate Muscles
have shorter fibers to parallel
arranged like a feather
arrangement increases the cross sectional are of the muscle so more power
Pennate Muscle Categorize
Unipennate
Bipennate
Multipennate
(if pennate is in the word, its a pennate muscle)
Muscle tissue: Skeletal Muscle has 4 Properties
Irritability or excitability
Contractility
Extensibility
Elasticity
Irritability or Excitability
property of muscle being sensitive or responsive to chemical (nerve), electrical, or mechanical stimuli
Contractility
Ability of muscle to contract and
develop tension or internal force against resistance ; when stimulated
Extensibility
Ability of muscle to be stretched beyond resting length
Elasticity
ability of muscle to return to original length after stretching
When you stimulate a muscle…
it contracts and produces force
When a muscle contracts…
one end will only move
Origin and assertion
Contraction
a muscle becomes tense due to stimulus
muscle contraction also means
muscle action
Isometric Contraction
the muscle stays the same length
joint angles remain constant
Types of Muscle contractions
Isometric
Isotonic
Isotonic
Concentric
Eccentric
Isotonic Contractions
muscle tension to cause or control movement
Passive Movement
movement without any muscle contraction
due to external force
Eccentric Contraction
muscle lengthening under tension
force from muscle is weaker than resistance
(still controlled)
Concentric Contraction
muscle shortens under tension
force from muscle is greater than resistance
