Download The Muscular System - Brownfield High School

Name: _____________________________________
Period:
2
4
The Muscular System
1. The Muscular System
a. Muscles are responsible for all types of __________________________
b. Three basic muscle types are found in the body
i. _____________________ muscle
ii. _____________________ muscle
iii. _____________________ muscle
2. Characteristics of Muscles
a. Skeletal and smooth muscle cells are ________________
i. (muscle cell = muscle fiber)
b. Contraction of muscles is due to the movement of microfilaments
c. All muscles share some terminology
i. Prefixes ______ and______ refer to “muscle”
ii. Prefix ________ refers to “flesh”
3. Comparison of Skeletal, Cardiac, and Smooth Muscles
a. Skeletal Muscle Characteristics
1. Most are attached by ___________ to
bones
2. Cells are______________
3. Striated—have
__________________________
4. Voluntary—subject to ______________
control
5. Cells are surrounded and bundled by
connective tissue
ii. Connective Tissue Wrappings of Skeletal
Muscle
1. ____________________—encloses a single muscle fiber
2. ____________________—wraps around a fascicle (bundle) of muscle fibers
3. ____________________—covers the entire skeletal muscle
4. _______________—on the outside of the epimysium
iii. Skeletal Muscle Attachments
1. Epimysium blends into a connective tissue attachment
a. Tendons—_________________________ structures
i. Mostly______________ fibers
ii. Often cross a joint due to ________________ and small size
b. Aponeuroses—_______________________structures
i. Attach muscles indirectly to bones, cartilages, or connective tissue
covering
2. Sites of muscle attachment
a. __________
b. _______________
c. _________________________________
b. Smooth Muscle Characteristics
i. ____________ striations
ii. ___________________________ cells
iii. Single nucleus
iv. ____________________—no conscious control
v. Found mainly in the walls of _______________ organs
c. Cardiac Muscle Characteristics
i. _______________________
ii. Usually has a single nucleus
iii. Joined to another muscle cell at an
_______________ disc
iv. ___________________
v. Found only ________________
4. Skeletal Muscle Functions
a. Produce __________________
b. Maintain _________________
c. Stabilize _________________
d. Generate ____________
5. Microscopic Anatomy of Skeletal Muscle
a. Cells are multinucleate
b. Nuclei are just beneath the sarcolemma
c. Sarcolemma—______________________
__________________________________
d. Sarcoplasmic reticulum—_____________
__________________________________
__________________________________
e. Myofibrils—long organelles inside muscle cell
i. Bundles of _____________________
ii. Myofibrils are aligned to give distinct bands
1. ___ band = _________ band
a. Contains only thin filaments
2. ___ band = _________ band
a. Contains the entire length of the thick filaments
f. Sarcomere—__________________ unit of a muscle fiber
i. Organization of the sarcomere
1. Thick filaments = ___________ filaments
a. Composed of the protein myosin
b. Has ATPase enzymes
2. Thin filaments = _________ filaments
a. Composed of the protein actin
ii. Physiology of the sarcomere
1. Myosin filaments have __________
(extensions, or cross bridges)
2. Myosin and actin ___________
somewhat
3. Anchored to the ____ disc
4. At rest, there is a bare zone that lacks
actin filaments called the ___ zone
5. Sarcoplasmic reticulum (SR)
a. Stores and releases _____________
6. Properties of Skeletal Muscle Activity
a. Excitability (also called responsiveness or irritability)—_________________________________
______________________________________________________________________________
b. Contractility—ability to shorten when an ____________________ is received
c. Extensibility—ability of muscle cells to be ________________
d. Elasticity—ability to _______________________________________________________ after
stretching
7. The Nerve Stimulus to Muscles
a. Skeletal muscles must be stimulated by a _________________________ (nerve cell) to contract
b. Motor unit—one motor neuron and all the skeletal muscle cells stimulated by that neuron
c. Neuromuscular junction
i. ________________________________________________________________________
d. Synaptic cleft - Gap between __________________________________
i. Nerve and muscle do not _______________________
ii. Area between nerve and muscle is filled with _______________________
8. Transmission of Nerve Impulse to Muscle
a. Neurotransmitter—chemical released by nerve upon arrival of nerve impulse
i. The neurotransmitter for skeletal muscle is _______________________________ (ACh)
b. Neurotransmitter (Acetylcholine) attaches to _______________________ on the sarcolemma
c. Sarcolemma becomes permeable to _________________ (Na+)
d. Sodium rushes into the cell generating an action potential
e. Once started, ___________________________________________________________
9. The Sliding Filament Theory of Muscle Contraction
a. Activation by nerve causes ____________________ (cross
bridges) to attach to _____________________ on the thin
filament
b. Myosin heads then bind to the next site of the
__________________ and pull them toward the center of
the _________________
c. This continued action causes a sliding of the ____________
along the ______________
d. The result is that the muscle is _____________(contracted)
10. Contraction of Skeletal Muscle
a. Muscle fiber contraction is “______________________”
b. Within a skeletal muscle, ______________________ may be stimulated during the same interval
c. Different _______________________ of muscle fiber contractions may give differing responses
d. Graded responses—_____________________________________________________________
______________________________________________
i. Graded responses can be produced by changing:
1. The _______________of muscle stimulation
2. The _______________ of muscle cells being stimulated at one time
ii. Types of Graded Responses
1. Twitch
a. ________________
________________
b. Not a ___________
muscle function
2. Tetanus (summing of
contractions)
a. One contraction is
immediately followed
by another
b. The muscle does not ______________________________________
c. The effects are added
3. Unfused (incomplete) tetanus
a. Some relaxation occurs between ____________________
b. The results are summed
4. Fused (complete) tetanus
a. No evidence of _________________ before the following contractions
b. The result is a _________________ muscle contraction
11. Muscle Response to Strong Stimuli
a. Muscle force depends upon the _________________________ stimulated
b. More fibers contracting results in ______________________________________
c. Muscles can continue to contract _______________________________________
12. Energy for Muscle Contraction
a. Initially, muscles use stored ATP for energy
i. ATP bonds are broken to release energy
ii. Only __________seconds worth of ATP is stored
by muscles
b. After this initial time, other
_______________________________ utilized to
produce ATP
13. Energy for Muscle Contraction
a. Direct phosphorylation
i. Muscle cells store
_____________________________________
(CP)
1. CP is a high-energy molecule
ii. After ATP is depleted, ADP is left
iii. CP transfers energy to ADP, to
________________ ATP
iv. CP supplies are exhausted in less than 15 seconds
b. Aerobic respiration
i. Series of _______________________________
that occur in the ____________________
ii. Glucose is broken down to __________________
____________________, releasing energy (ATP)
iii. This is a slower reaction that requires continuous
_________________
c. Anaerobic glycolysis
i. Reaction that breaks down _________________
without oxygen
ii. Glucose is broken down to ___________________
to produce some ATP
iii. Pyruvic acid is converted to __________________
iv. This reaction is not as efficient, but is __________
1. Huge amounts of glucose are needed
2. Lactic acid produces __________________
14. Energy for Muscle Contraction
a. Muscle Fatigue and Oxygen Deficit
i. When a muscle is _______________, it is unable
to contract even with a __________________
ii. Common cause for muscle fatigue is oxygen debt
1. Oxygen must be “_____________” to
tissue to remove oxygen deficit
2. Oxygen is required to get rid of accumulated ________________________
iii. Increasing _____________ (from lactic acid) and lack of ATP causes the muscle to
contract less
15. Types of Muscle Contractions
a. Isotonic contractions
i. _______________________ are able to slide past each other during contractions
ii. The muscle _______________________________________________________
b. Isometric contractions
i. ________________ in the muscles increases
ii. The muscle is unable ______________________________________________________
16. Muscle Tone
a. Some fibers are ________________________________________________________________
b. Different fibers contract at ________________________________ to provide muscle tone
c. The process of stimulating various fibers is under involuntary control
17. Effect of Exercise on Muscles
a. Exercise increases _____________________________________________________________
b. Aerobic (endurance) exercise (biking, jogging) results in stronger, more flexible muscles with
greater resistance to fatigue
c. Makes body metabolism more efficient
d. Improves _____________________________________________
e. Resistance (isometric) exercise increases muscle size and strength
f. Results of increased muscle use
i. Increase in muscle ____________
ii. Increase in muscle ________________
iii. Increase in muscle __________________
iv. Muscle becomes more fatigue resistant
18. Muscles and Body Movements
a. Movement is attained due to a muscle moving an
______________________
b. Muscles are attached to at least two points
i. Origin
1. Attachment to a _______________
_____________________
ii. Insertion
1. Attachment to an ______________
____________________________
19. Types of Ordinary Body Movements
a. Flexion
i. Decreases the_____________ of the joint
ii. Brings two bones ____________________________
iii. Typical of _____________ joints like knee and elbow
b. Extension
i. Opposite of flexion
ii. Increases angle between two bones
c. Rotation
i. Movement of a bone around its ____________________
ii. Common in ______________________
d. Abduction
i. Movement of a limb _________________ the midline
e. Adduction
i. Movement of a limb _________________ the midline
f. Circumduction
i. Common in _____________________________________
20. Special Movements
a. Dorsiflexion
i. Lifting the foot so that the superior surface approaches the shin
b. Plantar flexion
i. Depressing the foot (pointing the toes)
c. Inversion
i. Turn sole of foot medially
d. Eversion
i. Turn sole of foot laterally
e. Supination
i. Forearm rotates laterally so palm faces anteriorly
f. Pronation
i. Forearm rotates medially so palm faces posteriorly
g. Opposition
i. Move thumb to touch the tips of other fingers on the same hand
21. Types of Muscles
a. Prime mover—muscle with the _________________________________ for a certain movement
b. Antagonist—muscle that _____________________________________________ a prime mover
c. Synergist—muscle that aids a prime mover in a movement and helps prevent _______________
d. Fixator—___________________ the origin of a prime mover
22. Naming Skeletal Muscles
a. By direction of muscle fibers
i. Example: _______________(straight)
b. By relative size of the muscle
i. Example: __________________(largest)
c. By location of the muscle
i. Example: __________________ (temporal bone)
d. By number of origins
i. Example: _________________ (three heads)
e. By location of the muscle’s origin and insertion
i. Example: ________________ (on the sternum)
f. By shape of the muscle
i. Example: ________________ (triangular)
g. By action of the muscle
i. Example: __________________ and ________________(flexes or extends a bone)
23. Head and Neck Muscles
a. Facial muscles
i. Frontalis—raises eyebrows
ii. Orbicularis oculi—closes eyes, squints,
blinks, winks
iii. Orbicularis oris—closes mouth and
protrudes the lips
iv. Buccinator—flattens the cheek, chews
v. Zygomaticus—raises corners of the
mouth
b. Chewing muscles
i. Masseter—closes the jaw and elevates
mandible
ii. Temporalis—synergist of the masseter,
closes jaw
c. Neck muscles
i. Platysma—pulls the corners of the mouth inferiorly
ii. Sternocleidomastoid—flexes the neck, rotates the head
24. Anterior Muscles of Trunk, Shoulder, Arm
a. Anterior muscles
i. Pectoralis major—adducts and flexes the humerus
b. Intercostal muscles
i. External intercostals—raise rib cage during inhalation
ii. Internal intercostals—depress the rib cage to move air out of the lungs when you exhale
forcibly
25. Muscles of the abdominal girdle
a. Rectus abdominis—flexes vertebral column and compresses abdominal contents (defecation,
childbirth, forced breathing)
b. External and internal obliques—flex vertebral column; rotate trunk and bend it laterally
c. Transversus abdominis—compresses abdominal contents
26. Posterior Muscles of Trunk, Shoulder, Arm
a. Trapezius—elevates, depresses, adducts, and stabilizes the scapula
b. Latissimus dorsi—extends and adducts the humerus
c. Erector spinae—back extension
d. Quadratus lumborum—flexes the spine laterally
e. Deltoid—arm abduction
27. Muscles of the Upper Limb
a. Biceps brachii—supinates forearm, flexes elbow
b. Brachialis—elbow flexion
c. Brachioradialis—weak muscle
d. Triceps brachii—elbow extension (antagonist to biceps
brachii)
28. Muscles of the Lower Limb
a. Gluteus maximus—hip extension
b. Gluteus medius—hip abduction, steadies pelvis when
walking
c. Iliopsoas—hip flexion, keeps the upper body from falling
backward when standing erect
d. Adductor muscles—adduct the thighs
29. Muscles of the Pelvis, Hip, Thigh
30. Muscles causing movement at the knee joint
a. Hamstring group—thigh extension and knee flexion
b. Biceps femoris
c. Semimembranosus
d. Semitendinosus
e. Sartorius—flexes the thigh
f. Quadriceps group—extends the knee
g. Rectus femoris
h. Vastus muscles (three)
31. Muscles of the Lower Limb
a. Muscles causing movement at ankle and foot
i. Tibialis anterior—dorsiflexion and foot
inversion
ii. Extensor digitorum longus—toe
extension and dorsiflexion of the foot
iii. Fibularis muscles—plantar flexion,
everts the foot
iv. Soleus—plantar flexion