chapter 5 lesson 4 Flashcards
Skeletal muscle
The type of muscle tissue that connects to bones and generates the forces that create movement.
Fascia
Connective tissue that surrounds muscles and bones
Epimysium
Inner layer of fascia that directly surrounds an entire muscle, commonly referred to as deep fascia.
Fascicles
Largest bundles of fibers within a muscle. Fascicles are surrounded by perimysium.
perimysium
Connective tissue surrounding muscle fascicle
Glycogen
Glucose that is deposited and stored in bodily tissues, such as the liver and muscle cells; the storage form of carbohydrates.
myofibrils
The contractile components of a muscle cell; the myofilaments are contained within a myofibril. Individual muscle fiber is made up of this stuff.
myofilament
Are the actual contractile components of muscle tissue.
actin
Thin string like filaments.
myosin
Thin string like filaments.
sarcomere
The structural unit of a myofibril composed of actin and myosin filaments between two z lines.
Z line
The meeting points of each sarcomere.
Neural activation
The nervous systems signal that tells a muscle to contract
Neuromuscular junction
The specialized site where the nervous system communicates directly with muscle fibers
Synapse
A junction or small gap between the motor neuron and muscle cells
Motor unit
A motor neuron and all of the muscle fibers that it innervates.
Action potential
Is a nerve impulse that is relayed from the central nervous system through the peripheral nervous system and into the muscles across the neuromuscular junction
neurotransmitter
Are chemical messengers that cross the synapse between neuron and muscle. They also represent the translation of the nervous systems electrical message 8nto a form the neurotransmitters are released.
acetylcholine
A neurotransmitter used by the neuromuscular system.it helps action potential cross the synapse into the muscle which initiates the steps in a muscle contraction.
Sliding filament theory
The series of steps in muscle contraction involving how myosin and actin filaments slide past one another to produce a muscle contraction. Shortening the entire length of the sarcomere.
Excitation contraction coupling
The physiological process of converting an electrical stimulus to a muscle contraction.
Adenosine triphosphate (ATP)
To provide energy to the myosin heads
Power stroke
The overlapping action of the actin and myosin filament.
Resting length
Once the action potential forms the cns stops.
Type 1 muscle fibers
Muscle fibers that are small in size, generate lower amounts of force and are more resistant to fatigue.
Type 2 muscle fibers
Muscle fibers that are larger in size, generate higher amounts of force and are faster to fatigue,
All or nothing
Motor units cannot vary the amount of force they generate; they either contract maximally or not at all.
capillaries
The smallest blood vessels and the site of exchange of elements between the blood and the tissues.
