Which One of the Following Is Characteristic of Cardiac and Smooth

question 26

Multiple Choice

Which one of the following is characteristic of cardiac and smooth muscle, but not skeletal muscle?

• A) voluntary contraction
• B) striated appearance
• C) presence of gap junctions
• D) presence of actin and myosin in muscle cells
• E) contraction is initiated by motor neurons

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Definitions:

Ependymal Cells

Ciliated cells that line internal cavities of CNS; help produce and circulate cerebrospinal fluid.

Macrophage

A large phagocytic cell capable of ingesting and digesting bacteria and cell debris. Macrophages are also antigen-presenting cells.

Acetylcholine

Acetylcholine is a neurotransmitter involved in many functions including muscle activation, heart rate regulation, and the modulation of brain function.

Graded Potential

A shift in electrical charge across a neuron's membrane, varying in magnitude, that can initiate an action potential if it reaches a threshold.