11 Muscles (Lecture) Flashcards
Stiated and voluntary
Skeletal muscle
3 types of muscle
Skeletal, cardiac, smooth
Stiated and involuntary
Cardiac muscle
Unstriated and involuntary
Smooth muscle
Functions of skeletal muscle
Balance Reflex Sphincters Protects organs Generates heat
Superficial facia
Adipose tissue
Deep facia
Thin layer of connective tissue
Epimysium
Connective tissue that wraps around named muscles
Perimysium
Surrounds a muscle facilcle
Endomysium
Look up in lab manuel Wraps around each muscle fiber
Muscle segment
A named muscle
Fascicle
Holds a group of muscle cells
Muscle fiber
Another term for muscle cell
Origin
Point where a muscle attached stays stationary durning muscle contraction
Insertion
End of the muscle that moves
Agonist
Biceps
Antagonist
Opposes agonist Triceps
Synergistic muscles
Antagonist muscles that control fine movements
Sarcolemma
Muscle cell membrane. Can carry electrical signal spreads in waves Yellow stuff on model
Sarcoplasam
Fluid inside a muscle cell
Sarcoplasmic reticulum
Tends to store a large amount of calcium
The triad structure on a sarcomere is made of ? Parts and what are they?
T-tubules= 1 connects to little pores on the sarcolemma Cisterns= 2 runs between lateral sacs connects to sarcoplasmic reticulum
Myofibril
They are organelles Bundles of protein filaments
Myofillaments are ? What are the 2 types?
Proteins fibers Actin and myosin
Myosin
Thick and dark filament has spurs. Myosin heads (spurs) at the end of each filament engage with actin during a muscle contraction. Myosin stays stationary during contraction.
Actin
Light thin filaments Active sites where myosin heads attach Actin slides during muscle contraction
Sarcomere
Is the functional unit of a contraction. Extends from Z line to Z line
I band
Actin only z line is the middle
A band
Dark band actin and myosin overlap
H band
Middle of A band myosin only
M line
Dead center of sarcomere
Z line
Length of one sarcomere Includes A band, H band, M line, and about half of an I band on each end
Draw Sarcomere
DO IT

Motor end plate
Converts chemical signal into electrical signal
Synapse
Space between terminal button and motor end plate.
Terminal button aka synaptic terminal
Releases NTR into synapse
T-tubule
Electrical signal enters muscle through T tube
Cisterns
Contain large amounts of calcium. Electrical signal coming through t tubule stimulates cisterns to dump calcium.
what is the trigger for muscle contraction.
Calcium is the signal for a myosin head to attach to actin.
All or none principal
Only applies to skeletal muscle When the contact they contract completely or not at all. Heavy vs light object more or less cells contract.
Muscular Dystrophy
Inherited, it is a abnormal dystrophin protein. This protein normally strengthens the sarcolemma. Sarcolemma tears in MD people.
Myasthenia Gravis
Autoimmune disease that destroys the motor end plate.
Amyotrophic lateral sclerosis ( Lou Garrick’s)
Destroys motor neurons
Rigor Mortis
ATP required to hold calcium on cisterns
Tonic muscle contraction
Remains contracted after stimulation is gone .
Phasic muscle contraction
When a muscle contracts then relaxes
isometric action
muscular contraction against resistance in which the length of the muscle remains the same.
Isotonic action
muscular contraction against resistance in which the length of the muscle changes.
Motor units
One nerve and all the muscle cells it controls
Fine motor control
A nerve that controls one or a few muscle cells
Coarse muscle control
A nerve contracts 100 or more muscle cells
Number of origins
Biceps 2 Triceps 3 Quadriceps 4
Axial muscles
Move head, neck, veterbral column, pelvic floor, axial trunk(abdomin) They do not move appendages.
Galea Aponeurotica
Tendon sheet at the top of the head
Abdominal aponeuroses
Tendon sheet that covers abdomin
Linea alba
Tendon from xyphoid to pubis
Appendicular muscles
Move appendages
Rotator cuff muscles
Deltoid, Pectoralis major, infraspinatus, teres major, teres minor.
IM injection sites
Deltoid for adult Gluteus minimus for kids Rectus femorus for self injections
Lumbodorsal fascia
Tendon sheet for low back
Arm compartments (anterior compartments)
The muscles that flex the arm
Arm compartments (posterior)
The muscles that extend the arm (triceps)
Illiotibial tract
Tendon sheet on lateral side of thigh
Leg compartment (anterior)
Extending muscles
Leg compartments (posterior)
Flexing muscles
Leg compartments (medial)
Adducting
Leg compartments (lateral)
Abducting
Gait cycle phases
Stance phase 60% Weight bearing leg Begins when heel strikes ground and ends when toe lifts. Swing phase 40% Non weight bearing leg Begins when toes lifts off ground. Ends when heel strikes ground.
Smooth muscle
Wraps around tubes and vessels Controlled by ANS involuntary Longitudinal layer Contracts and tube will dilate Circular layer contracts tube will constrict

cardiac muscle
Quadraceps include
vastas medialis, vastas lateralis, vastas intermedius, rectus fermerus

Skeletal Muscle

Smooth Muscle

