Structure And Function Of Skeletal Muscle

Front 1

Three Types of Muscle

Back 1

Smooth, Cardiac, Skeletal

Front 2

Extensibility

Back 2

the ability to stretch so that it can be elongated-cannot elongate itself requires an external force such as another muscle group, or gravity

Front 3

Elasticity

Back 3

ability to return to normal length after the stretching force is removed

Front 4

Parallel Elastic Component (PEC)

Back 4

epimysium, permysium, endomysium

Front 5

Series elastic component (SEC)

Back 5

tendons

Front 6

Contractile Components

Back 6

Actin and Myosin

Front 7

Excitability

Back 7

the ability to respond to a stimulus, ordinarily comes from the nervous system

Front 8

Contractility

Back 8

the ability to apply tension or apply force

Front 9

Smooth Muscle Appearance

Back 9

lacks lines, single centrally located nucleus, spindle shape, small in size, fatigue resistant

Front 10

Smooth Muscle Location

Back 10

located on walls of hollow vicera, and the walls of blood vessels

Front 11

Smooth Muscle Regulation

Back 11

Autonomic or involuntary muscles

Front 12

Cardiac Muscle Appearance

Back 12

striated b/c of the arrangement of actin and myosin, contractile proteins are arranged into sarcomere, 1 or 2 nuclei per fiber, also branch out

Front 13

Cardiac Muscle Location and regulation

Back 13

found only in the heart

autonomic, self regulated with influence of the autonomic nervous system

Front 14

Skeletal Muscle Functions

Back 14

force production for locomotion and breathing, force production for postural support, heat production during cold stress(shivering)

Front 15

Skeletal muscle Appearance

Back 15

striated, many peripherally located nuclei 100's to 1000's, huge cells

long cylindrical muscle fibers, cells are not connected to each other, each fiber is a large cell, multinucleated, structurally independent cells

Front 16

Skeletal Muscle location and regulation

Back 16

located throughout the body and are voluntary muscles regulated by the somatic nervous system

Front 17

Skeletal Muscle Chem composition

Back 17

75% Water
20% Protein
5% Inorganic salts, etc.

Front 18

Epimysium

Back 18

surrounds the whole muscle, separates one muscle from another

Front 19

Perimysium

Back 19

surrounds and separates each fasciculus

Front 20

Fasciculus

Back 20

bundle of muscle fibers usually 12 to 150 fibers

Front 21

Endomysium

Back 21

surrounds and separates individual muscle fibers

Front 22

Nerve Supply Motor fibers

Back 22

(Efferent) From the Central nervous system out to the periphery, responsible for activating skeletal muscle

Front 23

Nerve Supply Sensory Fibers

Back 23

(Afferent) periphery back to the central nervous system, many different information types to be sent, pain, fatigue, etc. etc..

Front 24

Motor Unit

Back 24

A group of skeletal muscle fibers and the somatic motor neuron that controls them

Front 25

Alpha Motor Neuron

Back 25

Connects to the muscle fiber in the middle of the fiber
1 motor neuron can innervate many muscle fibers
1 muscle fiber is innervated by just 1 motor neuron

Front 26

Alpha Motor Neuron Cell Bodies

Back 26

generally found in the spinal cord, anterior gray horn of the spinal cord

Front 27

Synaptic Vesicles

Back 27

Store acetylcoline (ACH)

Front 28

Synaptic cleft

Back 28

gap in between the muscle fiber and axon terminal

Front 29

Sarcolemma

Back 29

cell membrane bi layer, when reaches the neuromuscular junction, changes shape and folds, becomes the Motor End Plate which contains many receptors for ACH

Amenable to change with training

Front 30

Small/fine movements

Back 30

few muscle fibers per motor unit gives fine control movements, examples threading a needle, typing

Front 31

Large/Coarse movements

Back 31

Gross(large) movement many muscle fibers per motor unit, posture balance, walking

Front 32

Muscle Cell Membrane (sarcolemma)

Back 32

encloses contents of the cell, regulates the passage of materials in and out of the cell, also evidence that stimuli can cause cell membrane to rupture

Front 33

Muscle microstructure-Nucleus

Back 33

contain the genetic material/DNA growth, etc. controlled by nucleus

Front 34

muscle microstructure- Cytoplasm (sarcoplasm)

Back 34

Fluid is cytosol, structures that have specialized functions are the organelles

Front 35

Sarcoplasm

Back 35

contains