Sinoatrial Node Cells

question 67

Multiple Choice

Sinoatrial node cells

• A)reach threshold only when action potentials generated by the AV node arrive through gap junctions.
• B)exhibit spontaneous depolarization that is speeded by activation of their cholinergic receptors.
• C)exhibit spontaneous depolarization that is speeded by activation of their beta-adrenergic receptors.
• D)exhibit a steep upstroke due to the presence of the same type of Na⁺ channels found in neuronal membranes. 
• E)are between atrial muscle cells and cells of the bundle of His.

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Definitions:

Annual Period

The annual period is a 12-month timeframe used in financial reporting, planning, and evaluation of a company's performance.