Cardiac Pacemakers Once Used Plutonium-238 as a Power Source $\gamma$ Rays And

question 113

Multiple Choice

Cardiac pacemakers once used plutonium-238 as a power source.Plutonium-238 decays by the emission of $\gamma$ rays and $\alpha$ particles.This emission is not particularly harmful because ________.

• A)"\(\gamma\) rays are not absorbed very strongly by biological tissue,and α particles do not penetrate beyond the container."
• B)"\(\gamma\) rays and \(\alpha\) particles are the least dangerous form of radiation."
• C)"\(\gamma\) rays and \(\alpha\) particles do not penetrate beyond the container."
• D)"\(\gamma\) rays are absorbed by the container,and \(\alpha\) particles do not affect biological tissue."
• E)"\(\beta\)^- particles are the most harmful type of radiation,and ²³⁸Pu is not a \(\beta\)^- emitter."

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Definitions:

Filium Terminale

A fibrous tissue extending from the conus medullaris of the spinal cord to the coccyx, providing longitudinal support to the spinal cord.

Dorsal Root Ganglion

A cluster of sensory neurons located in the dorsal root of a spinal nerve, transmitting sensory information to the spinal cord.

Ventral Root

A bundle of motor neuron fibers emerging from the anterior aspect of the spinal cord and conveying impulses from the central nervous system to the muscles.

Spinal Nerve

One of the 31 pairs of nerves that originate from the spinal cord, providing motor and sensory functions to the body.