Starting with a Sample of Pure ⁶⁶Cu, 7/8 of It

question 18

Multiple Choice

Starting with a sample of pure ⁶⁶Cu, 7/8 of it decays into Zn in 15 minutes. The corresponding half-life is:

• A) 15 minutes
• B) 5 minutes
• C) 7 minutes
• D) 3.75 minutes
• E) 10 minutes

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Definitions:

Threshold Level

The minimum level of stimulus intensity required to activate a neuron or to trigger a specific physiological response.

Repolarization Phase

Phase of the action potential in which the membrane potential moves from its maximum degree of depolarization toward the value of the resting membrane potential.

Voltage-gated Ion Channels

Proteins embedded in cell membranes that open or close in response to changes in membrane potential, crucial for the propagation of nerve impulses.

Plasma Membrane

A phospholipid bilayer that surrounds a cell, providing it with structural support and controlling the movement of substances into and out of the cell.