Cytoskeletal and Muscle Function Study Questions

These flashcards cover key vocabulary and concepts related to muscle function, neurotransmitter activity, and bone physiology.

Titin

A massive, thick filament-associated structural protein that limits sarcomere length when a muscle is stretched.

Nicotinic Acetylcholine Receptor (nAChR)

A nonspecific cation channel that allows passage of Na+, K+, and Ca2+, with Na+ influx dominating under normal physiological conditions.

Botulinum toxin type A

A protease that prevents exocytosis and release of acetylcholine from nerve terminals, used clinically to reduce synaptic acetylcholine levels.

Phospholamban

A regulatory protein associated with the cardiac sarcoplasmic reticulum Ca2+ ATPase that, when phosphorylated, increases the rate of SERCA function.

Ca2+-Induced Ca2+ Release (CICR)

A process mediated by ryanodine receptors which facilitates muscle contraction through calcium release from the sarcoplasmic reticulum.

Hydroxyapatite

A crystalline mineral containing calcium and phosphate that provides bones with strength and resilience.

RANKL (Receptor Activator of Nuclear Factor kB Ligand)

A ligand expressed on the surface of osteoblast precursors that facilitates bone resorption by binding to RANK on osteoclast precursors.

Pacini Corpuscles

Rapidly adapting tactile receptors responsible for sensing vibrations in the 40–500 Hz range, primarily found in glabrous skin.

Parathyroid Hormone (PTH)

A hormone that stimulates bone resorption and Ca2+ reabsorption from the kidneys when plasma calcium levels decrease.

L-type Ca2+ Channels

Voltage-gated channels that open in response to membrane depolarization, important for Ca2+ influx in muscle tissues.