Which of the Following Statements Regarding Contraction in Skeletal and Smooth

question 24

Multiple Choice

Which of the following statements regarding contraction in skeletal and smooth muscle is true?

• A)In skeletal muscle, calcium ion mediates changes in thin filaments that lead to cross-bridge activity; in smooth muscle, calcium ion mediates changes in thick filaments that lead to cross-bridge activity
• B)In skeletal muscle, calcium ion binds to a regulatory protein on thin filaments; in smooth muscle, calcium ion binds to a regulatory protein on thick filaments
• C)In skeletal muscle, calcium ion binds to troponin; in smooth muscle, calcium ion binds to calmodulin
• D)Both in skeletal muscle, calcium ion mediates changes in thin filaments that lead to cross-bridge activity; in smooth muscle, calcium ion mediates changes in thick filaments that lead to cross-bridge activity and in skeletal muscle, calcium ion binds to troponin; in smooth muscle, calcium ion binds to calmodulin are true
• E)All of the choices are true

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Definitions:

Voltage Flows

Incorrect terminology; voltage does not flow, but rather it is a measure of the electrical potential difference between two points.

Neutral Conductor

A conductor that is connected to a point of zero voltage in an electrical system, providing a return path for current in circuits where a neutral point is used.

Potential

Refers to the potential energy per unit charge at a point in a field or circuit, often associated with voltage or electric potential difference.

Coulomb

The standard unit of electric charge in the International System of Units (SI), equivalent to the charge transported by a constant current of one ampere in one second.