Biology Ames Test: Understanding Mutations and Lethality

[hidemi]

Homework Statement

In the Ames, the clear region of no growth near the center of the plate (where the compound of interest is placed) typically indicates that the compound is:
A) not mutagenic
B) an antibiotic
C) an amino acid
D0 lethat at high enough concertrations
E) not taken up by bacteria

The correct answer is D.

Relevant Equations

None

From my understanding, Ames test is the test for mutation, not lethality at high enough concentration. Let me know if my understanding is wrong.

 

[BillTre]

It detects mutations in particular genes using special strains made to survive when a mutation is made.
More colonies, more mutations.

There are lots of genetic tests and techniques, that use similar strategies, to quickly and easily show when a mutation has been made, so you can easily count them.

 

[hidemi]

From my understanding, Ames test is the test for mutation, not lethality at high enough concentration. Let me know if my understanding is wrong.

 

[BillTre]

It is not mutagenic (A).
If it made mutations, then some of the mutations would be able to survive where the compound was at high concentration.
No mutations, no survivors.

 

[Ygggdrasil]

The test is meant to detect mutagenic compounds, but a compound that is lethal to the bacteria would also have a detectable effect on the assay.

In the case of the question, I would think that (B) and (D) are both reasonable answers to the question.

 

[hidemi]

Thank you all! I understand!