Download Muscle Tissue

Primary Function
of the Muscular System
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Locomotion
movement of substances through the body
structure and support for organs and tissues
Muscle Tissue: 3 Types
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Muscle Tissue enables the movement of
body structures. Smooth, Cardiac, Skeletal
Muscle Types: Smooth Muscle
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Smooth muscle is
non-striated, and
acts in a number of
involuntary processes
in the body. Some of
these processes
include:
Muscle Types: Smooth Muscle
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allows the expansion and contraction of arteries
and veins
lines the bladder and reproductive tracts
lines the entire gastrointestinal tract
Did you know?...

Tiny smooth muscle fibers in the skin
called Arrector pili are responsible for
“goose bumps.”
Muscle Types: Cardiac Muscle

Cardiac muscle
(heart muscle) is
striated but functions
involuntarily. It is
solely responsible for
propelling blood
throughout the body.
Muscle Types: Skeletal Muscle

Skeletal muscle is striated, and
associated with voluntary movement. It
also provides structure and support for
organs and tissues.
Anatomy of skeletal muscles
tendon
Muscle
Fascicle
Skeletal
muscle
Skeletal
muscle
fiber (cell)
How Do Muscles Work?
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Individual muscle fibers are
composed of small cylindrical
structures called myofibrils.
The functional component
within the myofibril is called
the sarcomere.
Within the sacromere,
protein filaments called actin
and myosin allow the cell to
expand and contract in a
3 step process:
3 Steps
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1) Before the muscle is stimulated, actin and myosin
filaments partially overlap one another.
2) A nerve cell releases a signal which causes the actin
and myosin filaments to “slide” along one another and
overlap even more.
3) This contracts the myofibril and subsequently the
entire muscle cell. When the nervous signal changes, the
filaments relax and return to their original state.
Muscle
fiber
sarcomere
Z-line
myofibril
Actin
myosin
Thin myofilament
Myosin molecule of
thick myofilament
Sarcomere
Actin and Myosin: A Closer Look

Access the website below (skip to sections 6-10)
and complete the tutorial.
http://www.wiley.com/college/pratt/0471393878/st
udent/animations/actin_myosin/actin_myosin.swf
Action Potentials and the
Neuromuscular Junction
1.
Impulse arrives at axon terminal
Ca+ ions rush in activating
synaptic vesicles
2.
3.
4.
Synaptic vesicles fuse with cell
membrane of axon terminal
ACh released
ACh binds with motor end
plate: deplorization occurs
Impulse travels through
T-tubules & SR
Actin, Myosin, and Action Potentials
Putting it all Together…
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Access these online
animations to help visualize
these processes…
The Neuromuscular Junction

http://tinyurl.com/the-neuromuscularjunction
Action Potential and Muscle Contraction
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http://tinyurl.com/5qox4x
Sarcomere Contraction
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http://tinyurl.com/sarcomerecontraction
Did you Know?
If you check out a standard lass,
Muscles are a third of her body mass.
Muscle
(~35%)
BODY COMPOSITION
The Muscular System:
Key Components

Muscles move body parts because they’re
attached to bones by strips of dense
connective tissue called tendons.
Skeletal Muscle: Key Concepts
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The place where muscle attaches to a stationary
bone is called the “origin.” The place where the
same muscle attaches and “pulls” is called the
“insertion.”
Origin
Insertion
Skeletal Muscle: Key Concepts

Skeletal muscle can
be characterized as
either “extensors”
(causing a joint to
straighten or
extend), or a
“flexor” (causing a
joint to bend or flex).
Challenge question

How are
tendons
different from
ligaments?
Basic Muscle
Groups
You Need to
Know!
Basic Muscle
Groups
You Need to
Know!
Basic Muscle
Groups
You Need to
Know!
Naming Skeletal Muscles
Direction of
Muscle
Fibers
Location
Action
Skeletal
Muscle
Origin
&
Insertion
Size
Shape
Number
Of
Origins
Naming Muscles: By
Direction of Muscle Fibers
(Relative to the Midline)
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RECTUS = parallel to the
midline
 Rectus Abdominus
TRANSVERSE =
perpendicular to midline
 Transverse Abdominus
OBLIQUE = diagonal to
midline
 External Oblique
Naming Muscles: Location
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Structure near
which muscle is
found
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FRONTALIS =
near FRONTAL
bone
OCCIPITALIS =
near OCCIPITAL
bone
Naming Muscles: Size
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Relative Size of Muscle
MAXIMUS = largest
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MEDIUS = middle
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Fibularis Longus
BREVIS = short
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Gluteus Minimus
LONGUS = longest
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Gluteus Medius
MINIMUS = smallest
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Gluteus Maximus
Fibularis Brevis
TERTIUS = shortest
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Fibularis Tertius
Naming Muscles: Number of Origins
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Number of tendons of
origin
BICEPS = Two
 Biceps Brachii
 Biceps Femoris
TRICEPS = Three
 Triceps Brachii
QUADRICEPS =
Four
 Quadriceps Femoris
Naming Muscles: Shape
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Relative Shape of the
Muscle
DELTOID = triangular
shape Δ
TRAPEZIUS = trapezoid
shape 
SERRATUS = sawtoothed ♒
RHOMBOIDEUS =
rhomboid shape 
TERES = round ○
Naming Muscles: Action
NAME
FLEXOR
EXTENSOR
ACTION
EXAMPLE
Decrease angle at a joint
Flexor Carpi Radialis
Increase angle at a joint
Extensor Carpi Ulnaris
ABDUCTOR
Move bone away from
midline
Abductor Pollicis Longus
ADDUCTOR
LEVATOR
Move bone toward midline
Adductor Longus
Produce upward movement
Levator Scapulae
DEPRESSOR
Produce downward
movement
Depressor Labii Inferioris
SUPINATOR
Turn palm upward/anterior
Supinator
PRONATOR
Turn palm
downward/posterior
Pronator Teres
Cateorigizing muscles by
the Actions they Facilitate
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Prime mover– muscle with the major
responsibility for a certain movement
Antagonist – muscle that opposes or
reverses a prime mover
Synergist – muscle that aids a prime
mover in a movement and helps prevent
rotation
Fixator – stabilizes the origin of a prime
mover
Examples
__________
__________
__________
__________
Head & Neck Muscles
Head & Neck Muscles
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Frontalis: elevate
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Orbicularis Oculi: close
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eyebrows 
eyelid 
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Zygomaticus: draw
angle of lip upward 
Buccinator: draws
cheeks against teeth
Orbicularis Oris: closes
mouth 
Platysma: draws lower
lip down & back 
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Cranial Aponeurosis:
connects frontalis to
occipitalis
Temporalis: elevates
mandible
Occipitalis: draws scalp
back
Masseter: elevates
mandible
Sternocleidomastoid:
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Flexes head
Draws head toward
shoulder
Key Muscles of Facial Expression
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Smiling Muscles
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Orbicularis Oculi
Nasalis
Levator Labii
Superioris
Levator Anguli
Superioris
Zygomaticus
Risorius
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Frowning Muscles
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Frontalis
Orbicularis Oris
Depressor Anguli Oris
Depressor Labii
Inferioris
Mentalis
Platysma
Muscles of the Axial Skeleton
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Erector Spinae:
maintain posture
of back/extension
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Semispinalis
Multifidus
Rotatores
Respiratory Muscles
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Spinalis
Longissimus
Iliocostalis
Oblique Muscles:
rotation of the
vertebrae
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Diaphragm
External Intercostals
Internal Intercostals—deep
breaths
Abdominal Muscles
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External Obliques
Internal Obliques
Transverse Abdominus
Rectus Abdominus
Muscles of the Axial
Skeleton
Muscles of Scapular Stabilization
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Trapezius:
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Retraction
Elevation
Depression
Upward Rotation
Rhomboid—retraction
Levator Scapular—Elevation
Pectoralis Major—Protraction
Serratus Anterior—Protraction
Anterior Muscles of Shoulder
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Deltoid
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Pectoralis Major
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Flexion/Extension
Abduction/Adduction
Internal’External Rotation
Adduction
Flexion
Extension
Internal Rotation
Biceps Brachii—Flexion
Posterior Muscles of
Shoulder
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Teres Major
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Latissimus Dorsi
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Adduction
Extension
Internal Rotation
Adduction
Extension
Internal Rotation
Triceps Brachii
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Adduction
Extension
Rotator Cuff Muscles
(SITS)
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Supraspinatus
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Abduction
Infraspinatus
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External Rotation
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Teres Minor
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External Rotation
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Internal Rotation
Subscapularis
Muscles of the
Elbow/Forearm
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Triceps Brachii—
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Bicep Brachii—
Extension
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Brachialis—Flexion
Brachioradialis—
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Flexion
Supination
Flexion
Pronation
Pronator Teres
Pronator Quadratus
Supinator Longus
Muscles of the Wrist &
Hand
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Flexor Carpi
Ulnaris
Flexor Carpi
Radialis
Flexor Digitorum
Extensor Carpi
Ulnaris
Extensor Carpi
Radialis
Extensor
Digitorum
Anterior (Palmar) View
Posterior (Dorsal) View
Muscles of the Hip: Anterior
Medial/Adductor Muscles:
Adductor Magnus
Adductor Longus
Adductor Brevis
Gracilis
Anterior Muscles
Iliopsoas—Flexion
Pectineus—
Flexion
Adduction
Sartorius—
Flexion
Lateral Rotation
Muscles of the Hip: Gluteal
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Gluteus Maximus—
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Gluteus Medius—
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Gluteus Minimus—
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** Gluteus Minimus is under
the Gluteus Medius
Extension
Abduction
Abduction
Tensor Fasciae
Latae—
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Flexion
Abduction
Muscles of Anterior Thigh
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“Quadriceps”
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Rectus Femoris—
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Hip flexion
Knee extension
Vastus Lateralis—
knee extension
Vastus Medialis—knee
extension
Vastus Intermedius—
knee extension
Sartorius—
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Hip & Knee Flexion
Lateral Hip Rotation
**Vastus Intermedius is
beneath Rectus Femoris
Muscles of Posterior Thigh
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“Hamstrings”
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Responsible for
Knee Flexion & Hip
Extension
Semimembranosus
Semitendinosus
Biceps Femoris
Gastrocnemius
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Knee Flexion
Muscles of the Lower Leg
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Anterior Compartment
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Posterior Compartment
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Tibialis Anterior — Dorsiflexion &
inversion
Extensor Digitorum Longus
Fibularis Tertius — dorsiflexion &
eversion
Gastrocnemius — plantarflexion,
knee flexion
Soleus — plantarflexion
Lateral Compartment
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Fibularis Longus — plantarflexion
& eversion
Fibularis Brevis — plantarflexion
& eversion
Can you think of different ways in which
the muscular system works with other
body systems to maintain homeostasis?
Aerobic vs.
Anaerobic Exercise

Muscle contraction requires ATP. When oxygen
is present in sufficient amounts, the normal
processes of glycolysis and cellular
respiration can take place (aerobic).
However, if oxygen is not present in large
enough quantities to sustain vigorous muscle
contraction, only a small amount of ATP is
generated through glycolysis; and lactic acid
forms in the absence of cellular respiration
(anaerobic).
Pop
Quiz!
Identify
Skeletal
muscle groups
1-14
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“That’s All Folks!”
More to come…