3 types of muscle
Skeletal, cardiac, smooth
Stiated and voluntary
Stiated and involuntary
Unstriated and involuntary
Functions of skeletal muscle
Balance Reflex Sphincters Protects organs Generates heat
Thin layer of connective tissue
Connective tissue that wraps around named muscles
Surrounds a muscle facilcle
Look up in lab manuel Wraps around each muscle fiber
A named muscle
Holds a group of muscle cells
Another term for muscle cell
Point where a muscle attached stays stationary durning muscle contraction
End of the muscle that moves
Opposes agonist Triceps
Antagonist muscles that control fine movements
Muscle cell membrane. Can carry electrical signal spreads in waves Yellow stuff on model
Fluid inside a muscle cell
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
They are organelles Bundles of protein filaments
Myofillaments are ? What are the 2 types?
Proteins fibers Actin and 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.
Light thin filaments Active sites where myosin heads attach Actin slides during muscle contraction
Is the functional unit of a contraction. Extends from Z line to Z line
Actin only z line is the middle
Dark band actin and myosin overlap
Middle of A band myosin only
Dead center of sarcomere
Length of one sarcomere Includes A band, H band, M line, and about half of an I band on each end
Motor end plate
Converts chemical signal into electrical signal
Space between terminal button and motor end plate.
Terminal button aka synaptic terminal
Releases NTR into synapse
Electrical signal enters muscle through T tube
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.
Inherited, it is a abnormal dystrophin protein. This protein normally strengthens the sarcolemma. Sarcolemma tears in MD people.
Autoimmune disease that destroys the motor end plate.
Amyotrophic lateral sclerosis ( Lou Garrick's)
Destroys motor neurons
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
muscular contraction against resistance in which the length of the muscle remains the same.
muscular contraction against resistance in which the length of the muscle changes.
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
Move head, neck, veterbral column, pelvic floor, axial trunk(abdomin) They do not move appendages.
Tendon sheet at the top of the head
Tendon sheet that covers abdomin
Tendon from xyphoid to pubis
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
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)
Tendon sheet on lateral side of thigh
Leg compartment (anterior)
Leg compartments (posterior)
Leg compartments (medial)
Leg compartments (lateral)
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.
Wraps around tubes and vessels Controlled by ANS involuntary Longitudinal layer Contracts and tube will dilate Circular layer contracts tube will constrict
vastas medialis, vastas lateralis, vastas intermedius, rectus fermerus