The four main characteristics of muslce tissue.
Excitability (responsiveness); Contractility; Extensibility; Elasticity
Smallest contractile unit of muscle fiber
Sarcomere
This states that during contraction, thin filaments slide past thick filaments, causing actin and myosin to overlap more
The sliding filament model of contraction
The peripheral nervous system is divided into these two divisions.
Sensory (afferent) and Motor (efferent) divisions
Ion channels that are always kept open.
Leakage (non-gated) channels
This neurotransmitter receptor involves transmembrane protein complexes and causes widespread metabolic changes.
G protein–linked receptors
This connective tissue sheath is made of dense irregular connective tissue surrounding entire muscle
Epimysium
These extend across I band and partway in A band; Anchored to Z discs
Actin myofilaments
This is formed when myosin heads are allowed to bind to actin
Cross bridges
This cell monitors neurons, migrates towards injured ones, and phagocytizes microogranims
Microglial cells
Extracellular fluid (ECF) has higher concentrations of this ion than ICF.
Na+
_____: attachment to immovable or less movable bone
Origin
These are regulatory proteins bound to actin
Tropomyosin and troponin
The gel-filled space between an axon terminal and a muscle fiber
Synaptic cleft
A bundle of neuron processes in the CNS is called a _____ whereas in the PNS they are called _____.
Tract; nerves
This protein enzyme stabilizes resting membrane potential
Sodium-potassium pump (Na+/K+ ATPase)
a muscle fiber's plasma membrane
Sarcolemma
Runs longitudinally; regulates intracellular Ca2+ levels; stores and releases Ca2+
This neurotransmitter is released at an NMJ.
Acetylcholine (ACh)
Each neuron has one axon that starts at this cone-shaped area.
Axon hillock
This electrical/chemical signal does not decay over distance; referred to as a nerve impulse
Action potential
The perimysium is fibrous connective tissue surrounding these (groups of muscle fibers)
Fascicles
When an electrical impulse passes by, proteins in this structure change shape causing SR proteins to change shape, causing release of calcium into cytoplasm
T tubule
The events that transmit an AP along the sarcolemma coupled to sliding of myofilaments.
Excitation-contraction (E-C) coupling
Gaps between adjacent Schwann cells are called __.
Myelin sheath gaps (nodes of Ranvier)
_____ allows an AP to be transmitted from its origin down the entire axon length toward terminals
Propagation