Untitled Flashcards Set

Epimysium

Surrounds the entire muscle.

Perimysium

Surrounds bundles of muscle fibers (fascicles).

Epimysium

Surrounds the entire muscle.

Perimysium

Surrounds bundles of muscle fibers (fascicles).

Endomysium

Surrounds individual muscle fibers.

Basement membrane

Located just below the endomysium.

Sarcolemma

The muscle cell membrane.

Satellite cells

Play a key role in muscle growth and repair.

Myonuclear domain

Volume of cytoplasm surrounding each nucleus; limited in size for each nucleus.

NMJ

Junction between motor neuron and muscle fiber.

Motor end plate

Pocket formed around motor neuron by the sarcolemma.

Neuromuscular cleft

Short gap between neuron and muscle fiber.

Acetylcholine

Neurotransmitter released from the motor neuron that causes muscle depolarization.

End-plate potential (EPP)

Depolarization of the muscle fiber caused by acetylcholine.

Sliding filament theory

Huxley's theory that explains muscle contraction via sarcomere shortening.

Crossbridge formation

Process of myosin heads attaching to actin filaments leading to power stroke in muscle contraction. (sarcomere shortening)

Excitation contraction coupling

The process by which excitation of the motor end plate is coupled to muscle contraction.

Myosin ATPase

Enzyme that provides energy for muscle contraction.

Muscle biopsy

Procedure that involves removing a small piece of muscle for analysis.

Immunohistochemical staining

Techniques that use antibodies to differentiate fiber types based on color.

Gel electrophoresis

Method to identify myosin isoforms by separating them on a gel.

Firing rate of motor units

Frequency of stimulation affecting muscle contraction strength.

Post activation potentiation

Improved muscle performance following a warm-up or fatiguing exercise.

during muscle growth

satellite cells increase the number of nuclei in mature muscle fibers (reside above the sarcolemma)

z lines

What lines shorten/get closer together?

contractile history of muscle

rested muscle vs muscle exposed to fatiguing exercise