The Plateau of the Cardiac Action Potential Results from the Opening

question 13

Multiple Choice

The plateau of the cardiac action potential results from the opening of voltage-gated slow ____ channels in the plasma membrane of the ____ cell.

• A)sodium; contractile
• B)potassium; autorhythmic
• C)calcium; contractile
• D)chloride; pacemaker
• E)potassium; contractile

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Definitions:

Vertebra Prominens

The vertebra prominens refers to the most prominent vertebra, usually the C7 vertebra, marked by a longer and more palpable spinous process.

Axis

The second cervical vertebra (C2) of the spine, which allows the head to rotate.

Dens of the Axis

A prominent feature of the second cervical vertebra (axis), providing a pivot that allows the head and the atlas to rotate around the spinal axis.

Transverse Process

A bony projection off the side of each vertebra in the spine, to which muscles and ligaments attach.