In Certain Kinds of Muscle Cells, Calcium Ions Are Stored

question 127

Multiple Choice

In certain kinds of muscle cells, calcium ions are stored in ________.

• A) the smooth ER
• B) the rough ER
• C) both smooth and rough ER
• D) the cytoplasm

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Definitions:

Dendritic Spine

Protrusion that greatly increases the dendrite’s surface area; typical point of dendritic contact with the axons of other cells.

Postsynaptic Membrane

A specialized area of a neuron's cell membrane that receives neurotransmitters from another neuron at a synapse.

Electrical Synapses

Rapid, bidirectional connections between neurons mediated through gap junctions, allowing direct transmission of electrical signals.

Ion Channels

Proteins that form pores in cell membranes, allowing the selective passage of ions across the membrane and influencing the cell's electrical charge and signaling.