Title: Muscular System
1Muscular System
- Muscle Tissue
- The Muscular System
2Muscle Tissue
- Introduction
- Skeletal Muscle Tissue The Muscular System
- Anatomy of Skeletal Muscle
- Contraction of Skeletal Muscle
- Muscle Mechanics
3Muscle Tissue
- Aging the Muscular System
- Integration With Other Systems
- Cardiac Muscle Tissue
- Smooth Muscle Tissue
4Introduction
- Importance to body function
- Importance to human activity
- Active passive forces
5Learning Objectives
- Importance
- Discuss the central role of muscle tissue in a
variety of human activities and necessary body
functions - Active Forces
- Compare contrast tension, compression,
resistance
6ImportanceFunction Activity
- Human activity
- gross movements of the body
- communication
- speaking
- facial expression gestures
- Body function
- circulation
- respiration
- digestion
- reproduction
7Body Movement
8Communication
9Bodily Functions
10Active Passive Forces
- Resistance
- passive force opposing movement
- dependent on weight, shape, friction, etc
- Tension
- active force applied to an object to produce
movement - when applied tension gt resistance, object is
pulled toward source of tension - Compression (not assoc. w/ muscle movement)
- active force applied to an object to produce
movement - when applied compression gt resistance, object is
pushed away from source of compression
11Muscle Contraction Produces Tension
RESISTANCE
TENSION
12Skeletal Muscle Tissue The Muscular System
- Tissue characteristics
- Functions of muscle tissue
13Learning Objectives
- Characteristics Functions
- Describe the characteristics functions of
muscle tissue
14Muscle Tissue
- One of 4 primary tissue types of the body
- Types of muscle tissue
- skeletal
- cardiac
- smooth
- Body muscles are organs
- that contain skeletal muscle tissue, connective
tissues, nerves, epithelial tissue smooth
muscle tissue (in blood vessels)
15Muscle Tissue Types
skeletal muscle
smooth muscle
cardiac muscle
16Functions ofSkeletal Muscle Tissue
- Produce skeletal movement
- Maintain posture body position
- Support soft tissues
- Guard entrances into exists out of the body
- Maintain body temperature
Mr. G
Before he got married
17Anatomy of Skeletal Muscle
- Connective tissue organization
- Blood vessels nerves
- Microanatomy of skeletal muscle fibers
18Learning Objectives
- Tissue Structure
- Describe the organization of muscle at the tissue
level - Cellular Structure
- Explain the unique characteristics of skeletal
muscle fibers - Organelle Structure
- Identify the structural components of a sarcomere
19Connective TissueOrganization
- Surrounding Sheaths
- Epimysium
- Perimysium
- Endomysium
- Tendons
20Connective Tissue Organization
- Epimysium
- outer connective tissue layer
- dense layer of collagen fibers
- deep fascia
- surrounds entire muscle
- Perimysium
- middle connective tissue layer
- collagen elastic fibers
- contains blood vessels nerves
- surrounds fascicles dividing muscle into
compartments
21Connective Tissue Organization
- Endomysium
- inner connective tissue layer
- delicate c.t.
- surrounds muscle fibers satellite cells
- satellite cells (stem cells)
22Connective Tissue Organization
- Epimysium, perimysium, endomysium unite at
muscle ends to form - Tendons
- linear bundle attaching muscle to bone
- Aponeuroses
- broad sheet attaching muscle to bone same
function as tendon
23Connective Tissue Organization
Animation
24Blood Vessels Nerves
blood vessels
nerve
25Microanatomy
- Organelles of Skeletal Muscle Fibers
- Sarcomere Organization
- Microfilament Structure
26Microanatomy of Skeletal Muscle Fibers
- Muscle fiber muscle cell
- long, thin (among largest cells in body)
- multinucleate peripheral, oval nuclei
- Sarcolemma cell membrane
- openings for penetrating tubules
- established membrane potential due to Na-K ion
exchange pumps
27Microanatomy of Skeletal Muscle Fibers
- Sarcoplasm cytoplasm
- contains contractile proteins
- contains numerous mitochondria
- Sarcoplasmic reticulum (SR) endoplasmic
reticulum - terminal cisternae fused SR tubules
- triads regions where T tubules SR cisternae
contact
28Microanatomy of Skeletal Muscle Fibers
- Transverse tubules T tubules
- continuous w/ sarcolemma
- network throughout cell
- close contact w/ SR
- Myofibrils
- 100s-1000s of bundles of myofilaments
- thin filaments
- thick filaments
29Microanatomy of Skeletal Muscle Fibers
- Sarcomere
- repeating units in myofibrils
- linked end-to-end
- functional unit of a muscle fiber
- components
- thick protein filaments
- thin protein filaments
- proteins stabilizing thick thin filaments
- proteins regulating interaction btw/ thin thick
filaments
30Sarcomere Organization
- Banded appearance due to overlap of thick thin
filaments - A bands appear dark
- I bands appear light
- A band contains thick thin filaments
- M line
- center of sarcomere
- thick filaments only - connected by stabilizing
protein
31Sarcomere Organization
- A band (cont)
- H zones
- lateral to M line
- thick filaments only
- Zones of overlap
- lateral to H zones
- thick thin filaments overlap
32Sarcomere Organization
- I bands contain thin filaments only
- edges of sarcomere
- Z lines
- boundaries btw/ adjacent sarcomeres
- protein complexes attached to thin filaments
33Sarcomere Organization
Note A I bands peripheral nuclei
A
I
34Functional Organization
35Thin Filaments
- Composition (proteins)
- F actin
- twisted filament of G actin globular proteins
- contains active sites that can bind to thick
filaments - tropomyosin
- protein cover over active sites of F actin
- troponin
- binds tropomyosin to active site
- contains Ca2 receptor
36Thin Filaments
- Troponin-tropomyosin complex
- reacts to bound Ca2 by uncovering active sites
on F actin of thin filament - necessary for contraction
37Thick Filaments
- Composition (protein)
- myosin
- subunits tail head
- tail
- binds to other myosin molecules
- head
- projects outward toward thin filament
- called cross-bridges
38Thick Thin Filament Structure
39ContractionOf Skeletal Muscle
- The control of skeletal muscle activity
- Relaxation
- The contraction cycle
- Length-tension relationships
40Learning Objectives
- Neuromuscular Junction
- Identify the components of the neuromuscular
junction summarize the events involved in the
neural control of skeletal muscle function - Muscle Cell Contraction
- Explain the key steps involved in the contraction
of a skeletal muscle fiber
41Control of Skeletal Muscle Activity
- Neuromuscular junction
- neural axon branch terminates w/ synaptic
terminal at every muscle fiber - synaptic terminal contains neurotransmitter
acetylcholine (ACh) - synaptic cleft separates terminal from muscle
fiber sarcolemma
42Control of Skeletal Muscle Activity
- Neuromuscular junction
- motor end plate sarcolemma surface w/ ACh
receptors - acetylcholinesterase (AChE) in cleft breaks
down ACh - ACh receptors of motor end plate bind to ACh
released from synaptic terminal and respond by
opening gated ion channels in sarcolemma
43Membrane PotentialElectrochemical Gradient
positive charge due to ? Na
negative charge due to ? protein ? a.a. ?
F.A.
44Neural Stimulation of Muscle Fibers
- Step 1. Arrival of action potential.
- action potential electric impulse travels down
axon of neuron - enters synaptic terminal of neuron
- Step 2. Release of ACh.
- exocytosis synaptic vesicles containing ACh
fuse w/ neurolemma - ACh enters synaptic cleft
45Neural Stimulation of Muscle Fibers
- Step 3. ACh binds at motor end plate.
- ACh diffuses across cleft binds to ACh
receptors of sarcolemma - gated Na-channel proteins open sarcolemma
becomes permeable to Na - Na floods into sarcoplasm
46Neural Stimulation of Muscle Fibers
- Step 4. Appearance of action potential in
sarcolemma. - Na influx results in action potential at motor
end plate - action potential spreads across the excitable
sarcolemma down T tubules - action potential affects SR
47Neural Stimulation of Muscle Fibers
- Step 5. Return to initial state.
- AChE in cleft breaks down ACh
- ACh unbinds from receptors
- gated Na-channels close Na is pumped back out
of sarcoplasm by Na-K ion pumps
48Steps 1 5
49Contraction Relaxation
- Excitation-Contraction Coupling
- action potential impulses cause release of Ca2
from SR - Ca2 binds to F actin of myofibrils to initiate
sarcomere contraction - continued reception of impulses causes continued
contraction - Relaxation
- Ca2 is reabsorbed by SR
- sarcomeres cease contraction
50Sarcomere Contraction Cycle
- Step 1. Active site exposure.
- Ca2 released from SR binds to troponin
- troponin pulls tropomyosin away from active site
on F actin - Step 2. Cross-bridge attachment.
- myosin heads (cross-bridges) bind to exposed
active sites of F actin
51Sarcomere Contraction Cycle
- Step 3. Pivoting of myosin head.
- cocked myosin heads are bent away from M line
due to stored energy from breakdown of ATP to ADP
Pi - ADP Pi remain bound to heads in resting
sarcomere - attachment of myosin head to active site of F
actin releases stored energy to create a power
stroke of head toward M line - ADP Pi are released as stroke occurs
52Sarcomere Contraction Cycle
- Step 4. Cross-bridge detachment.
- ATP binds to myosin head following stroke
- head unbinds from active site
- exposed active site available for binding to next
myosin head along length of myosin filament
53Sarcomere Contraction Cycle
- Step 5. Myosin reactivation.
- ATP ? ADP Pi
- released energy recockes myosin head
- Cycle can now be repeated under
- conditions
- ? Ca2 maintained
- ? ATP maintained
54(No Transcript)
55Observations of Sarcomere During Muscle
Contraction
sliding filament theory
56Sarcomere Contraction
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Additional Animation
57Muscle Mechanics
- Tension production
- Energetics of muscular activity
- Muscle performance
58Learning Objectives
- Muscle Contraction
- Explain the all-or-nothing principle of muscle
contraction - Discuss the structure function of a motor unit
- Distinguish between isotonic isometric
contraction - Energetics
- Describe the mechanisms by which muscle fibers
obtain the energy to power contractions
59Muscle ContractionTension Production
- All-or-None Principle
- muscle fibers are either stimulated to the point
of contraction or not - once stimulated, the entire muscle fiber
contracts - Tension produced by whole skeletal muscle due to
- frequency of stimulation
- of fibers stimulated w/in muscle
60Muscle ContractionMotor Unit
- Motor unit
- A single motor neuron all the muscle fibers
controlled by it - Motor unit size
- 4-6 fibers in eye muscles provide precise
control of movement - 1000-2000 in leg muscles provide less precise
control
61Muscle ContractionMotor Unit
- Recruitment
- Smooth, steady increase in the number of motor
units involved in a muscle contraction - a.k.a., multiple motor unit summation
- Muscle tone
- some motor units w/in a muscle are always active
- switch off w/ resting units regularly to
distribute activity
62Isotonic Muscle Contraction
- Isotonic contraction
- Tension plateaus muscle changes length
- concentric contraction
- tension gt resistance muscle shortens
- ex lifting weight
- eccentric contraction
- peak tension lt resistance muscle elongates
due to contraction of another muscle or gravity - ex lowering weight
63Isometric Muscle Contraction
- Isometric contraction
- tension varies but does not overcome resistance
- muscle does not shorten
- Note individual muscle fibers shorten until
tendons are taught external tension internal
tension generated by fibers - ex holding a weight stationary pushing
against an immovable object
64Charles Atlas
65Muscle Relaxation Return to Resting Length
- Causes of muscle relaxation
- Recoil of stretched elastic fibers in perimyzium
- Contractions of opposing muscles
- Gravity
66Energetics of Muscle Activity
- ATP is produced by cellular respiration in muscle
fibers - At rest, excess ATP energy stored as creatine
phosphate (CP) - ATP creatine ?
- ADP creatine phosphate
67Energetics of Muscle Activity
- During contraction myosin cross-bridges beak down
ATP to ADP Pi - Energy stored as creatine phosphate (CP)
recharges ADP - ADP creatine phosphate
- ? ATP creatine
68Aerobic Energy Metabolism O2 Present
- Glycolysis
- in cytosol of cytoplasm
- C6H12O6 ? 2 pyruvate
- yields 2 ATP (net)
- Aerobic cellular respiration
- in mitochondria
- 2 pyruvate 6O2 ? 6CO2 6H2O
- yields 25-34 ATP
69Storage Compounds
OO
glycogen stores glucose
myoglobin stores O2
70Anaerobic Energy Metabolism O2 Absent
- Glycolysis
- in cytosol of cytoplasm
- C6H12O6 ? 2 pyruvate
- yields 2 ATP (net)
- Lactic acid fermentation
- in cytosol
- 2 pyruvate ? 2 lactic acid
- yields 0 ATP
71Muscle ActivityResting
Muscle ActivityModerate
Muscle ActivityStrenuous
72Learning Objectives
- Fiber Types
- Relate the types of muscle fibers to muscle
performance - Aerobic Anaerobic Endurance
- Distinguish between aerobic anaerobic endurance
explain their implications for muscle
performance
73Fiber Types Fast
- Fast twitch muscle fibers
- contract w/in 0.01 sec after stimulation
- large diameter
- densely packed myofibrils
- reserves ? glycogen ? myoglobin
- few mitochondria
- Powerful contraction w/ rapid fatigue
- deplete ATP reserves rapidly
- activity supported by anaerobic metabolism
- Pale reddish color
74Fiber Types Slow
- Slow twitch muscle fibers
- contract w/in 0.03 sec after stimulation
- small diameter
- fewer myofibrils
- reserves ? myoglobin ? lipid ? glycogen
- many mitochondria
- Moderate contraction w/ slow fatigue
- deplete ATP reserves more slowly
- activity supported by aerobic metabolism
- Dark reddish color
75Fiber Types Intermediate
- Intermediate muscle fibers
- properties intermediate btw/ fast twitch slow
twitch - Pale reddish color
- Note
- Human muscles contain mixtures of 3 types
- Content varies w/ genetics use
76Muscle Size
- Hypertrophy
- increase in muscle mass
- muscle fibers constant
- diameter of muscle fibers ?
- Atrophy
- decrease in muscle mass
- muscle fibers constant
- diameter of muscle fibers ?
77Anaerobic Endurance
- Length of time muscular contraction can continue
supported by glycolysis existing reserves of
ATP CP - Limited by
- Amount of ATP CP on hand
- Amount of available glycogen
- ability of muscle to tolerate lactic acid
78Anaerobic Endurance
- Training regimen
- Frequent, short-duration exercise w/ intensive
levels of muscular activity - Ex sprinting speed swimming weight lifting
basketball
79Aerobic Endurance
- Length of time muscular contraction can continue
supported by mitochondrial activity - Limited by
- Amount of substrates from breakdown of
carbohydrates, fatty acids, /or amino acids - Amount of available oxygen
80Aerobic Endurance
- Training regimen
- Sustained, long duration exercise w/ low levels
of muscular activity - Ex jogging cross country running distance
swimming dance movements
81Aging The Muscular System
- Effects of aging on the bodys skeletal muscles
- Effect of life style on aging of muscles
82Learning Objectives
- Aging
- Specify 4 effects of aging on muscles
- Discuss how regular exercise early in life can
counter the effects of aging on the muscular
system
83Effects of Aging
- Skeletal muscle fibers decrease in diameter
- ? in myofibrils
- Skeletal muscles lose elasticity
- fibrosis ? collagen content
- Tolerance for exercise decreases
- ? thermoregulatory ability
- ? rate of fatigue
- Ability to recover from muscular injuries
decreases - satellite cells ?
- ? collagen content
84Life Style Aging
- Rate of decline in muscle performance is same for
all individuals regardless of exercise patterns
or lifestyle - To be in good shape late in life you must be
in very good shape early in life - Regular, moderate exercise is more important than
extremely demanding exercise
85Integration With Other Systems
- Dependence on other body systems
- Responses of body systems to muscular activity
86Learning Objectives
- Integration
- Discuss the interaction responses of 5 specific
body systems to muscular activity
87Integration Support From Other Body Systems
- Cardiovascular System
- ? heart rate dilation of blood vessels cause
- ? O2 delivery CO2 removal
- transports heat to skin for radiation to
environment - Respiratory System
- ? respiratory rate depth of respiration
- ? O2 delivery CO2 removal
- Integumentary System
- dilation of blood vessels ? sweating
- removes excess heat that would interfere w/
muscle protein activity
88Integration Support From Other Body Systems
- Nervous System
- controls voluntary muscle contraction
- regulates/coordinates cardiovascular,
respiratory, integumentary system activities - Endocrine System
- regulates/coordinates cardiovascular,
respiratory, integumentary system activities - maintains Ca2 -PO43- in blood other body
fluids via skeletal, digestive, urinary systems
89Integration Bones, Joints, Muscles
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90Cardiac Muscle Tissue
- Structural differences between cardiac skeletal
muscle tissues - Functional differences between cardiac skeletal
muscle tissues - The role of cardiac muscle in the body
91Learning Objectives
- Structure Function
- Identify the structural functional differences
between cardiac muscle tissue the other types
of muscle tissue - Discuss the role that cardiac muscle plays in the
cardiovascular system
92CardiocytesStructural Organization
- Single nucleus
- Branched cellular structure
- Striated myofibrils sarcomeres
- T tubules short broad no triads
- SR no terminal cisternae
- Mitochondria ?
- Intercalated discs btw/ adjacent cells
transfer contractions from one cell to several
others instantaneously
93CardiocytesFunctional Features
- Automaticity contraction w/out neural
stimulation - pacemaker cells
- Innervation alters pace of contraction
- Duration of contraction 10 X longer
- Sarcolemma characteristics prevent summation
tetany - Dependent on aerobic metabolism ?
mitochondria ? myoglobin
94SmoothMuscle Tissue
- Structural differences between smooth skeletal
muscle tissues - Functional differences between smooth skeletal
muscle tissues - The role of smooth muscle in body systems
95Learning Objectives
- Structure Function
- Identify the structural functional differences
between smooth muscle tissue the other types of
muscle tissue - Discuss the role that smooth muscle plays in
various body systems
96Smooth Muscle CellsStructural Organization
- Single nucleus
- Spindle-shaped cellular structure
- Non-striated no myofibrils or sarcomeres thick
thin filaments scattered through cytoplasm - Dense body network attach to thin filaments
to sarcolemma - No T tubules
- SR loose network
- Connective tissue sheaths do not unite to form
tendons or aponeuroses
97Smooth Muscle CellFunctional Features
- Excitation-Contraction coupling Ca2 enter cell
from extracellular fluid bind to calmodulin
which activates myosin light chain kinase to
break down ATP initiate contraction - Plasticity length-tension relationship allows
for variable contraction length
98Smooth Muscle CellFunctional Features
- Control of contraction involuntary many cells
not innervated respond to nearby smooth muscle
cells - multiunit smooth muscle cells connected to 1 or
more motor neurons leisurely contraction - loci iris of eye ? reproductive tract large
arteries arrector pili muscles - visceral smooth muscle cells many lack direct
neural contact - loci digestive tract urinary gall bladders
many internal organs
smooth muscle sheet
99The Muscular System
- Introduction
- Biomechanics Muscle Anatomy
- Muscle Terminology
- The Axial Muscles
- The Appendicular Muscles
100Introduction
- Voluntary control
- Form function
- Factors determining the effects of contraction
101Muscles
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102Learning Objectives
- Muscle Control
- Relate the muscular system to nervous control
- Muscle Shape
- Discuss how the structure of a muscle provides
clues to its primary function - Effects of Muscle Contraction
- Discuss 2 factors that interact to determine the
effect of a muscles contraction
103Voluntary Muscles
- Muscular System
- All muscles controlled voluntarily
- 700 identified
- 20 studied in book
- 30 studied for course
- Form function
- locomotor muscles - stretch across joints
- soft tissue support muscles - form sheets or
slings - muscles guarding body entrances - form rings
104Voluntary Muscles
- Effects of contraction determined by
- anatomical arrangement of muscle fibers
- attachment points of muscle to bones
105Biomechanics Muscle Anatomy
- Organization of skeletal muscle fibers
- Skeletal muscle length-tension relationships
- Levers
106Learning Objectives
- Fascicles
- Describe the arrangement of fascicles in the
various types of muscles explain the resulting
functional differences - Levers
- Describe the different classes of levers how
they make muscles more efficient
107Organization of Skeletal Muscle Fibers
- Fascicles
- bundles of muscle fibers w/in a muscle
- Patterns of fascicle organization
- parallel muscles fascicles parallel to long
axis of muscle - central body or belly w/ tendons at ends (most
muscles) - some w/ broad attachments aponeuroses
- Ex biceps brachii
108Organization of Skeletal Muscle Fibers
- Patterns of fascicle organization
- convergent muscles fascicles begin over a broad
area narrow to a single tendon or tendinous
sheet - raphe some attach to band of collagen fibers
- Ex pectoralis major
109Organization of Skeletal Muscle Fibers
- Patterns of fascicle organization
- pennate muscles fascicles form common angle w/
tendon - feather-shaped
- unipennate all fascicles on same side of
tendon Ex tensor digitorum - bipennate fascicles on both sides of
tendon Ex rectus femoris - multipennate tendon fascicles branch Ex
deltoid
110Organization of Skeletal Muscle Fibers
- Patterns of fascicle organization
- circular muscles fascicles concentrically
arranged around opening or recess - contraction ? decrease in diameter
- Ex orbicularis oris
111Fascicle Arrangements
112Length-TensionRelationships
- Muscles develop maximum tension over a narrow
range of sarcomere length - stretched muscle less overlap of thick thin
filaments in sarcomere - contracted muscle normal thick-thin filament
relationship is disrupted - Ex when curling weights flexion is harder to
achieve when arm muscles are stretched in
extended arm, becomes easier as muscles contract,
then harder after full flexion is achieved
113Length-TensionRelationships
- During complex movement muscles work in groups
- smaller muscles aid larger muscles to reach
length where maximum tension can be achieved
114Levers
- Lever rigid structure that moves on a fixed
point called the fulcrum - In body, each bone is a lever each joint is a
fulcrum - Lever action
- change direction of an applied force
- change distance speed of movement produced by
applied force - change the effective strength of an applied force
115Classes of Levers
- First-class - fulcrum btw/ AF R
- like see-saw
- Ex muscles that extend neck
- Second-class - R btw/ AF fulcrum
- like loaded wheelbarrow
- Ex calf muscles during plantar flexion
- Third-class - AF btw/ R fulcrum
- opposite of 2nd-class
- most common lever action of body
- Ex biceps brachii during flexion
116Muscle Terminology
- Origins insertions
- Actions
- Names of skeletal muscles
- Divisions of the muscular system
117Learning Objectives
- Origins Insertions
- Predict the actions of a muscle on the basis of
the relative positions of its origin insertion - Movements
- Explain how muscles interact to produce or oppose
movements - Muscle Names
- Explain how the name of a muscle can help
identify its location, appearance, and/or function
118Origins Insertions
- Origin
- beginning point of muscle attachment
- usually remains stationary bone that moves
little or not at all - usually proximal on limb
- Insertion
- end point of muscle attachment
- usually moves bone that moves
- usually distal on limb
119Actions
- Actions include flexion, extension, adduction,
etc - In terms of bone affected
- textbook ex flexion of the forearm
- In terms of joint affected
- professional ex flexion of the elbow
120Primary Actions
- Agonist
- prime mover muscle chiefly responsible for a
movement - Ex biceps brachii flexes elbow
- Antagonist
- prime mover muscle chiefly responsible for
the opposite action of the agonist - Ex triceps brachii extends elbow
121Primary Actions
- Synergist
- assists action of prime mover agonist or
antagonist - aid in action of prime mover
- fixator - stabilizes origin of prime mover by
preventing competing movement at a joint
122Naming Skeletal Muscles
- Fascicle organization
- rectus straight fascicles parallel to long
axis of body - transversus across fascicles perpendicular to
long axis of body - obliquus oblique fascicles angled to long axis
of body - Location
- brachii arm
- femoris thigh
123Naming Skeletal Muscles
- Relative position
- externus, extrinsic, superficialis outer body
surface - internus, intrinsic, profundus beneath the body
surface - Structure
- biceps 2 tendons of origin
- quadriceps 4 tendons of origin
- Shape
- deltoid triangular
- orbicularis circular
124Naming Skeletal Muscles
- Size length
- longus longissimus long longest
(respectively) - vastus large
- teres long round
- brevis short
- magnus, major, maximus big, bigger, biggest
(respectively) - minor minimus smaller smallest
(respectively)
125Naming Skeletal Muscles
- Position relative to body axis
- anterior front
- posterior back
- lateralis toward side
- medialis toward midline
- Origin insertion
- sternohyoid origin on sternum, insertion on
hyoid bone
126Naming Skeletal Muscles
- Action
- flexor causes flexion
- extensor, tensor causes extension
- depressor causes lowering of body part
- buccinator trumpeter (muscle that purses lips)
- sartorius tailor-like (muscle that allows
crossing of legs)
127Muscular System
- Divisions of the Muscular System
- axial musculature
- positions head spinal column
- moves rib cage
- 60 of all muscles
- appendicular musculature
- stabilizes moves the arms legs
- 40 of all muscles
128Axial Muscles
- Muscles of the head neck
- Muscles of the spine
- Oblique rectus muscles
- Muscles of the pelvic floor
129Learning Objectives
- Axial Muscles
- Identify the principal axial muscles of the body
together with their origins, insertions, actions,
innervation
130Muscles of theHead Neck
- orbicularis oris
- orbicularis oculi
- oculomotor muscles
- zygomaticus major minor
- buccinator
- masseter
- sternocleidomastoid
- platysma
131Muscles of the Face
132Oculomotor Muscles
133Muscles of the Torso
- scalenes
- external intercostals
- internal intercostals
- external oblique
- rectus abdominis
- diaphragm
134Appendicular Muscles
- Muscles of the shoulders upper limbs
- Muscles of the lower limbs
- Musculoskeletal compartments
135Learning Objectives
- Appendicular Muscles
- Identify the principal appendicular muscles of
the body together with their origins, insertions,
actions, innervation - Compare the major muscle groups of the upper
lower limbs relate their differences to their
functional roles
136Muscles of the Shoulder
- trapezius
- serratus anterior
- pectoralis minor
- pectoralis major
- latissimus dorsi
- deltoid
137Muscles of the Upper Limb
- triceps brachii
- biceps brachii
- brachioradialis
- brachialis
- extensor muscles (general locus)
- flexor muscles (general locus)
138Muscles of the Anterior Thigh
- rectus femoris
- vastus lateralis
- vastus medialis
- vastus intermedius
- sartorius
- gracilis
quadriceps femoris
139Muscles of theAnterior Thigh
140Muscles of the Lateral Posterior Thigh
- tensor fasciae latae
- gluteus maximus
- semitendinosis
- biceps femoris
- semimembranosis
hamstrings
141Muscles of the Lower Leg
- gastocnemius
- calcaneal tendon (Achilles tendon)
- soleus
- tibialis anterior
- peroneus longus
- peroneus brevis
142Muscles of theAnterior Lower Leg
143Musculoskeletal Compartments
144Muscular SystemOverview