Download ANATOMY OF THE SKELETAL SYSTEM

 Macro
MUSCLES
Some slides produced by
DR. VINIT.K.ASHOK
ADJUNCT FACULTY
MUSCLES

MUSCLES ATTACHED TO THE SKELETON ARE CALLED
SKELETAL MUSCLES AND THEY FORM THE BULK OF THE
MUSCULATURE IN THE HUMAN BODY
FUNCTIONS (of skeletal muscle)
-BRING ABOUT MOVEMENT IN THE BODY
-RESPONSIBLE FOR FACIAL EXPRESSIONS( FACIAL MUSCLES)
-GIVES SHAPE TO THE BODY
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CLASSIFICATIONBASED ON THE LOCATION
-name associated w/ region or bone found near
ex. Temporalis- located over
Temporal
Bone
BASED ON SHAPE OF MUSCLE
-name associated with shape
ex. Deltoid- triangular, Trapeziustrapezoid
BASED ON SIZE
-self explanitory
ex. Maximus/ minimus, longus, brevis
DIRECTION OF MUSCLE FIBERS
-direction of fibers usually in reference to
midline
ex. Rectus femorus
ex. Transversus abdominis
(reference
handouts)
ex. External oblique
CLASSIFICATION part 2
BASED ON NUMBER OF ORIGINS
-number of heads/origins
ex. Biceps, triceps, quadriceps
(Ceps= cephaly=head)
BASED ON LOCATION OF ORIGIN AND/OR INSERTION
-named due to attachment point.
-origin is named first
ex. Sternocleidomastoid
(Reference
BASED ON ACTION OF MUSCLE
handout)
-named for their action
ex. Adductor longus – medial thigh
ex. Supinator- guess where that is?
BONE MUSCLE RELATIONSHIP
LEVER SYSTEMS
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
LEVER SYSTEM-CONSISTS OF A
 RIGID BAR ( LEVER) WHICH MOVES ON A
 FIXED POINT ( FULCRUM) WHEN A
 FORCE IS APPLIED( EFFORT) TO MOVE A
 RESISTANCE( LOAD)
THE BONES AND MUSCLES IN THE BODY ACT AS LEVER
SYSTEMS




BONES
JOINTS
MUSCLES CONTRACTING
BONE ITSELF + overlying tissues + other material you are
trying to move
LEVER SYSTEM
TYPES OF LEVERS
FIRST CLASS LEVERS-FULCRUM LIES BETWEEN THE EFFORT AND THE LOAD( SEE-
SAW)
EFFORT IS APPLIED AT ONE END AND LOAD LIES ON THE
OTHER END
SECOND CLASS LEVERS
-LOAD LIES BETWEEN EFFORT AND FULCRUM(
WHEELBARROW)
GREATER STRENGTH, LESS SPEED AND RANGE OF ACTION
THIRD CLASS LEVERS
-
EFFORT LIES BETWEEN LOAD AND FUNCTIONFAST LARGE
MOVEMENTS WITH LITTLE EFFORT
MOST SKELETAL MUSCLES ARE OF THIS TYPE
 1st
CLASS LEVER
Let’s go to the
weight room!
 What
Where is fulcrum?
Where is effort?
Where is load?
muscle?
Second class levers
2nd class lever
Plantar flexion to
raise body on
toesWhat are the
muscles being
used for the
effort?
Load
Effort
THIRD CLASS LEVERS
3rd Class Levers
fulcrum
OPERATION OF SKELETAL
MUSCLES


FUNCTION TYPES BASED ON ACTIONS
-PRIME MOVER/AGONIST- THE MUSCLE THAT IS
RESPONSIBLE FOR A SPECIFIC ACTION


ANTAGONIST – MUSCLES THAT OPPSE A PARTICULAR
ACTION( RELXED WHEN AGONIST ARE ACTING


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BICEPS FLEXES THE FOREARM AT THE ELBOW
TRICEPS ARE RELAXED WHEN BICEPS ACT
SYNERGISTS- THESE ACT ALONG WITH AGONISTS ADD A
LITTLE EXTRA FORCE TO THE ACTION
FIXATORS- THEY HELP THE AGONIST BY HOLDING A BONE
IN PLACE
DIFFERENCES BETWEEN SKELETAL,SMOOTH AND
CARDIAC MUSCLES (microscopic)

-
-
SKELETAL MUSCLES
VOLUNTARY MUSCLE
STRIATED
NOT BRANCHED
MULTINUCLEATED( NUCLEUS
PRESENT PERIPHERALLY)
NOT BRANCHED
CYLINDRICAL IN SHAPE
PRESENT INRELATION TO BONES
SMOOTH MUSCLES
-INVOLUNTARY MUSCLE
-NOT STRIATED
-SPINDLE SHAPED
-SINGLE CENTRAL NUCLEUS
-PRESENT IN RELATION TO ORGANS( GIT)

CARDIAC MUSCLES
-INVOLUNTARY MUSCLE
-STRIATED
-BRANCHED
-SINGLE CENTRAL NUCLEUS
-CYLINDRICAL IN SHAPE
-PRESENT ONLY IN THE HEART
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