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Chapter 10
Muscular
Tissue
Lecture slides prepared by Curtis DeFriez, Weber State University
• Like nervous tissue, muscles are excitable or "irritable”
they have the ability to respond to a stimulus• Unlike nerves, however, muscles are also:
Contractible (they can shorten
in length)
Extensible (they can extend or
stretch)
Elastic (they can return to their
original shape)
Functions of Muscular Tissue
• Muscle makes up a large percentage of the body’s
weight
• Their main functions are to:
Create motion – muscles work with nerves, bones, and joints
to produce body movements
Stabilize body positions and maintain posture
Store substances within the body using sphincters
Move substances by peristaltic contractions
Generate heat through thermogenesis
Functions of Muscular Tissue
Location Function Appearance Control
Skeletal
skeleton
movement,
heat,
posture
striated, multi-
nucleated
(eccentric), fibers
parallel
voluntary
Cardiac
heartpump blood
continuously
striated, one
central nucleus
involunta
ry
Visceral
(smooth
muscle)
G.I. tract,
uterus, eye,
blood
vessels
Peristalsis,
blood
pressure,
pupil size,
erects hairs
no striations,
one central
nucleus
involunta
ry
Three Types of Muscular Tissue
(b) Cardiac muscle (c) Visceral smooth muscle
(a) Skeletal muscle
Three Types of Muscular Tissue
Location Function Appearance Control
Skeletal
skeleton
movement,
heat,
posture
striated, multi-
nucleated
(eccentric), fibers
parallel
voluntar
y
Cardiac
heartpump blood
continuously
striated, one
central nucleus
involunta
ry
Visceral
(smooth
muscle)
G.I. tract,
uterus, eye,
blood
vessels
Peristalsis,
blood
pressure,
pupil size,
erects hairs
no striations,
one central
nucleus
involunta
ry
Skeletal Muscle
Skeletal Muscle
Skeletal muscle fibers are very long “cells” -
next to neurons (which can be over a meter
long),
perhaps the longest in the body
The Sartorious muscle contains
single fibers that are at least
30 cm long
A single skeletal muscle fiber
Skeletal Muscle
Sarcolemma
Motor neuron
Skeletal Muscle
The terminal processes of a
motor neuron in close proximity
to the sarcolemma of a skeletal
muscle fiber
The epimysium, perimysium, and
endomysium all are continuous with
the connective tissues that form
tendons and ligaments (attach
skeletal muscle to bone) and muscle
fascia (connect muscles to other
muscles to form groups of muscles)
Organization of Muscle Tissue
Organization of Muscle Tissue
Organization of a single muscle
belly
Epimysium
Perimysium
Organization of a fasciculus
Organization of Muscle Tissue
Organization of a muscle fiber
Organization of Muscle Tissue
A muscle, a fasciculus, and a fiber all visualized
Organization of Muscle Tissue
• In groups of muscles the
epimysium continues to
become thicker, forming
fascia which covers many
muscles
• This graphic shows the
fascia lata enveloping the
entire group of quadriceps
and hamstring muscles in
the thing
Organization of Muscle Tissue
Organization of Muscle
Tissue• Many large muscle
groups are encased
in both a superficial
and a deep fascia
Real Anatomy, John Wiley and Sons