In 1913, an Element Was Known to "Emanate" from Radium-226

question 66

Multiple Choice

In 1913, an element was known to "emanate" from radium-226 by alpha emission and then to decay to polonium-218, also by  emission. What was the unknown element?

• A) radon-222
• B) lead-214
• C) plutonium-238
• D) bismuth-214
• E) lead-218

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Definitions:

Bacterial Colony

A visible mass of microorganisms all originating from a single mother cell, growing together on a solid medium.

Recombinant Plasmid

A circular DNA molecule engineered to carry specific gene sequences, used in genetic engineering to clone or express particular genes.

DNA Probe

A labeled single-stranded DNA fragment used to detect a gene of interest in a hybridization experiment.

cDNA Libraries

Collections of complementary DNA (cDNA) molecules synthesized from the messenger RNA of an organism, used to study gene expression and protein function.