Sinoatrial Node Cells

question 75

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 in-between atrial muscle cells and cells of the bundle of His.

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Definitions:

Transporting Oxygen

The primary function of the respiratory and circulatory systems, allowing oxygen to be inhaled into the lungs, carried by red blood cells, and delivered to tissue.

Tissue Cells

The basic structural and functional units of tissues in living organisms, varying widely in structure and function based on their location and task.

Coagulation

The process of blood changing from a liquid to a gel, forming a blood clot, which is an essential part of hemostasis to stop bleeding.

Agglutination

The clumping together of particles, typically cells or proteins, often caused by an antigen-antibody reaction.