Download The Muscular System

The Muscular System
 Muscles are responsible for all types of body ___________________
 Three basic muscle types are found in the body
 __________________ muscle
 __________________ muscle
 __________________ muscle
Characteristics of Muscles
 _______________ and _________________ muscle cells are ___________
(muscle cell = muscle fiber)
 _____________________ of muscles is due to the movement of
________________________________
 All muscles share some terminology
 Prefixes ________ and _________ refer to “_____________”
 Prefix ______________ refers to “______________”
Comparison of Skeletal, Cardiac, and Smooth Muscles
Skeletal Muscle Characteristics
 Most are attached by ______________ to bones
 Cells are ______________________
 ___________________—have visible banding
 ____________________—subject to conscious control
Connective Tissue Wrappings of Skeletal Muscle
 Cells are surrounded and bundled by __________________ tissue
 ________________________—encloses a single muscle fiber
 ________________________—wraps around a fascicle (bundle) of muscle
fibers
 ________________________—covers the entire skeletal muscle
 __________________—on the outside of the epimysium
Skeletal Muscle Attachments
 ______________________ blends into a connective tissue attachment
 __________________—cord-like structures
 Mostly _______________ fibers
 Often cross a ____________ due to toughness and ________ size
 _______________________—sheet-like structures
 Attach muscles _________________ to bones, cartilages, or
connective tissue coverings
 Sites of muscle attachment
 ______________
 ________________
 _____________________ tissue coverings
Smooth Muscle Characteristics
 Lacks __________________
 ________________-shaped cells
 _______________ nucleus
 ______________________—no conscious control
 Found mainly in the ___________ of ______________ organs
Cardiac Muscle Characteristics
 ___________________
 Usually has a ______________ nucleus
 __________________ cells
 Joined to another muscle cell at an _____________________ disc
 _________________________
 Found only in the ______________
Skeletal Muscle Functions
 Produce ___________________
 Maintain ___________________
 Stabilize _______________
 Generate ______________
Microscopic Anatomy of Skeletal Muscle
 _______________________—specialized plasma membrane
 _____________________—long organelles inside muscle cell
 ____________________ reticulum—specialized smooth endoplasmic
reticulum
 ___________________ are aligned to give distinct __________
 I band = ___________ band
 Contains only _________ filaments
 A band = __________ band
 Contains the entire length of the __________ filaments
 _____________________—contractile unit of a muscle fiber
 Organization of the sarcomere
 __________________
 ___________ filaments = _______________ filaments
 ___________ filaments = _______________ filaments
 Thick filaments = _________________ filaments
 Composed of the _____________ myosin
 Has _______________ enzymes
 Myosin filaments have ___________ (____________, or cross bridges)
 Myosin and actin _____________ somewhat
 Thin filaments = _______________ filaments
 Composed of the ________________ actin
 Anchored to the ___ ________
 At _______, there is a ________ zone that lacks _________ filaments called
the ___ ____
 Sarcoplasmic ________________ (SR)
 Stores and releases __________________
 __________________ the myofibril
Stimulation and Contraction of Single Skeletal Muscle Cells
 _________________________ (also called _____________________ or
irritability)—ability to ____________ and ________________ to a stimulus
 __________________________—ability to _______________ when an
adequate stimulus is received
 ________________________—ability of muscle cells to be _____________
 _____________________—ability to ___________ and resume resting
______________ after stretching
The Nerve Stimulus and Action Potential
 Skeletal muscles must be stimulated by a motor _____________ (nerve cell) to
_______________
 ____________ unit—one motor ___________ and all the _____________
muscle cells stimulated by that neuron
 ___________________________ junction
 Association site of ________ terminal of the motor neuron and muscle
 _________________ cleft
 Gap between ___________ and _______________
 Nerve and muscle do not make _______________
 Area between nerve and muscle is filled with _________________ fluid
Transmission of Nerve Impulse to Muscle
 _______________________________—_______________ released by nerve
upon arrival of nerve impulse
 The neurotransmitter for skeletal muscle is _________________ (ACh)
 Acetylcholine attaches to ______________ on the __________________
 Sarcolemma becomes _________________ to _______________ (Na+)
 _______________ rushes into the cell generating an __________
_____________
 Once started, muscle ___________________ cannot be ______________
The Sliding Filament Theory of Muscle Contraction
 Activation by nerve causes _____________ heads (_________ bridges) to
attach to ______________ sites on the _________ filament
 ____________ heads then bind to the next site of the _______ filament and
pull them ____________ the center of the ___________________
 This continued action causes a ______________ of the __________ along the
___________
 The result is that the muscle is _______________ (__________________)
Contraction of Skeletal Muscle
 Muscle fiber contraction is “____________________________”
 Within a skeletal muscle, not all fibers may be _________________ during the
same ________________
 Different combinations of muscle fiber contractions may give differing
responses
 _______________ responses—different _____________ of skeletal muscle
______________________
 Graded responses can be produced by changing
 The ____________________ of muscle stimulation
 The ___________________ of muscle cells being stimulated at one time
Types of Graded Responses
 ________________
 Single, brief contraction
 Not a normal muscle function
 _______________________ (summing of contractions)
 One contraction is immediately followed by another
 The muscle does not completely
return to a resting state
 The effects are added
 __________________ (incomplete) ________________
 Some relaxation occurs between contractions
 The results are summed
 _________________ (complete) __________________
 No evidence of relaxation before the following contractions
 The result is a sustained muscle contraction
Muscle Response to Strong Stimuli
 Muscle force depends upon the ______________ of fibers stimulated
 More fibers contracting results in ______________ muscle tension
 Muscles can continue to contract unless they run out of ___________
Energy for Muscle Contraction
 Initially, muscles use stored __________ for energy
 ATP bonds are __________________ to release energy
 Only ___________________ worth of ATP is stored by muscles
 After this initial time, other ___________ must be utilized to produce ATP
 Direct ________________________ of ADP by __________ phosphate (CP)
 Muscle cells store _______
 CP is a __________-energy molecule
 After ATP is depleted, ADP is left
 CP transfers energy to ADP, to regenerate ATP
 CP supplies are exhausted in less than ________ seconds
 _________________ respiration
 _______________ is broken down to carbon dioxide and water, releasing
energy (________)
 This is a slower reaction that requires continuous ____________
 A series of metabolic pathways occur in the _________________
 ____________________ glycolysis and lactic acid formation
 Reaction that breaks down glucose _______________ oxygen
 Glucose is broken down to pyruvic acid to produce some ATP
 Pyruvic acid is converted to lactic acid
 This reaction is not as ___________________, but is fast
 Huge amounts of ______________ are needed
 Lactic acid produces muscle ________________
Muscle Fatigue and Oxygen Deficit
 When a muscle is fatigued, it is unable to ________________ even with a
_________
 Common cause for muscle fatigue is ______________ debt
 Oxygen must be “_____________” to tissue to remove oxygen deficit
 Oxygen is required to get rid of accumulated ____________ acid
 Increasing _______________ (from lactic acid) and lack of _________ causes
the muscle to contract less
Types of Muscle Contractions
 __________________ contractions
 _____________________ are able to slide past each other during
contractions
 The muscle _______________ and ___________________ occurs
 ______________________ contractions
 Tension in the muscles ___________________
 The muscle is ______________ to shorten or produce movement
Effect of Exercise on Muscles
 Exercise increases muscle ________, ____________, and ____________
 Aerobic (_________________) exercise (biking, jogging) results in
______________, more ______________ muscles with greater resistance
to ______________
 Makes body metabolism more _________________
 Improves _______________, _____________________
 Resistance (_________________) exercise (weight lifting) increases
muscle _________ and ________________
Muscles and Body Movements
 Movement is attained due to a muscle moving an attached __________
 Muscles are attached to at least ________ points
 _______________
 Attachment to a ________________ bone
 _______________
 Attachment to an _________________ bone
Types of Muscles
 ______________ mover—muscle with the ______________ responsibility for
a certain movement
 ____________________—muscle that _____________ or reverses a prime
mover
 __________________—muscle that __________ a prime mover in a
movement and helps prevent rotation
 ________________—____________________ the origin of a prime mover
Naming Skeletal Muscles
 By ____________________ of muscle fibers
 Example: Rectus (______________)
 By relative ___________ of the muscle
 Example: Maximus (________________)
 By ________________ of the muscle
 Example: Temporalis (__________________ bone)
 By number of ______________
 Example: Triceps (___________ heads)
 By ______________ of the muscle’s origin and insertion
 Example: Sterno (on the _____________)
 By ______________ of the muscle
 Example: Deltoid (____________________)
 By _____________ of the muscle
 Example: Flexor and extensor (flexes or extends a bone)
Head and Neck Muscles
 Facial muscles
 _________________—raises eyebrows
 _________________ oculi—closes eyes, squints, blinks, winks
 ________________ oris—closes mouth and protrudes the lips
 ____________________—flattens the cheek, chews
 _______________________—raises corners of the mouth
 Chewing muscles
 _________________—closes the jaw and elevates mandible
 ____________________—synergist of the masseter, closes jaw
 Neck muscles
 _________________—pulls the corners of the mouth inferiorly
 ___________________________—flexes the neck, rotates the head
Muscles of Trunk, Shoulder, Arm
 Anterior muscles
 ________________ major—adducts and flexes the humerus
 Intercostal muscles
 External __________________—raise rib cage during inhalation
 Internal intercostals—____________ the rib cage to move air out of the
lungs when you exhale forcibly
 Muscles of the abdominal girdle
 Rectus _________________-—flexes vertebral column and compresses
abdominal contents (defecation, childbirth, forced breathing)
 External and internal _______________—flex vertebral column; rotate
trunk and bend it laterally
 __________________ abdominis—compresses abdominal contents
 Posterior muscles
 ________________—elevates, depresses, adducts, and stabilizes the
scapula
 _________________ dorsi—extends and adducts the humerus
 Erector _____________—back extension
 ___________________ lumborum—flexes the spine laterally
 ________________—arm abduction
Muscles of the Upper Limb
 ____________ brachii—supinates forearm, flexes elbow
 ____________—elbow flexion
 _______________________—weak muscle
 _____________ brachii—elbow extension (antagonist to biceps brachii)
Muscles of the Lower Limb
 ______________ _______________—hip extension
 Gluteus ______________—hip abduction, steadies pelvis when walking
 _________________—hip flexion, keeps the upper body from falling backward
when standing erect
 _____________________ muscles—adduct the thighs
 Muscles causing movement at the knee joint
 ____________________ group—thigh extension and knee flexion
 Biceps _____________
 ________________________
 ________________________
 Muscles causing movement at the knee joint
 _________________—flexes the thigh
 __________________ group—extends the knee
 Rectus ________________
 Vastus muscles (______________)
 Muscles causing movement at ankle and foot
 ___________________ anterior—dorsiflexion and foot inversion
 Extensor ___________________ longus—toe extension and dorsiflexion of
the foot
 _________ muscles—plantar flexion, everts the foot
 _______________—plantar flexion