When an Unstable Nucleus Expels a Positron ________

question 29

Multiple Choice

When an unstable nucleus expels a positron ________.

• A) its mass number is decreased by four units
• B) its atomic number is decreased by one unit
• C) its atomic number is increased by one unit
• D) its mass number is decreased by one unit

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Definitions:

Refractory Period

A time directly following stimulation in which a nerve or muscle is incapable of responding to more stimulation.

Synapse

The junction or region between the axon of one neuron and the dendrites or cell body of another, through which nerve impulses pass.

Depolarization

A decrease in the difference of electrical charge across a membrane, which can initiate an action potential in neurons.

Neural Membrane

The lipid bi-layer that encloses the cytoplasm of neurons, playing a key role in the transmission of electrical signals within the nervous system.