The doubling dose concept is defined as the dose required to double what?

The doubling dose concept is defined as the dose required to double what?

• A. The dose required to double the mutation rate
• B. The dose required to double the probability of chromosomal aberrations
• C. The dose that doubles organism size
• D. The dose required to double cell division rate

Answer: (A)

The doubling dose is a measure of mutagenicity defined by the dose of radiation (or another mutagen) needed to double the spontaneous mutation rate in a given gene or generation. This makes it the best answer because the concept specifically targets the frequency of new genetic changes, not growth outcomes or chromosomal changes in general. It’s about how often mutations occur, so the dose that doubles that rate is the defining quantity. In practice, a lower doubling dose means a mutagen is more potent, since less exposure is needed to double the mutation rate.

The doubling dose is a measure of mutagenicity defined by the dose of radiation (or another mutagen) needed to double the spontaneous mutation rate in a given gene or generation. This makes it the best answer because the concept specifically targets the frequency of new genetic changes, not growth outcomes or chromosomal changes in general. It’s about how often mutations occur, so the dose that doubles that rate is the defining quantity. In practice, a lower doubling dose means a mutagen is more potent, since less exposure is needed to double the mutation rate.