Question

Three biology students make very different predictions about the percent of mutations that will affect mouse proteins under normal conditions. Their predictions are 10 percent, 50 percent, and 90 percent. The students also disagree on whether tobacco smoke or ultraviolet radiation will affect the percentage.

Which student do you think made the most reasonable prediction for the percent of mutations that will affect mouse proteins under normal conditions? Will the percentage be affected by the presence of tobacco smoke or ultraviolet radiation? Defend your claims with logical reasoning.

A. 10% is the most reasonable prediction. Many base pairs in DNA are not a part of genes. Even if a mutation occurs in a gene, its effect may be silent because of the redundancy of the genetic code. The percentage is not likely to be affected by mutagens, such as tobacco smoke & radiation. Although mutagens increase the number of mutations, the percent of mutations that affect proteins should remain the same.

B. 50% is the most reasonable prediction. All base pairs in DNA are a part of genes. If a mutation occurs in a gene, it will always be expressed even though the genetic code may be redundant. The percentage poses a 1/2 chance to be effected by mutagens, such as tobacco smoke or cleaning chemicals, so the percent of mutations that affect proteins should increase.

Answer 1

The prediction of 10 percent is the most reasonable for mutations affecting mouse proteins, with mutagens like tobacco smoke or radiation increasing mutation frequency but not necessarily the proportion impacting protein function.

Step-by-step explanation:

The most reasonable prediction for the percent of mutations that will affect mouse proteins under normal conditions is 10 percent. Most DNA does not make up genes, and even when a mutation occurs within a gene, due to the redundancy of the genetic code, it may not result in a change in the protein.

Also, not all mutations are equally likely to affect protein function; some might be silent, others may have minor effects, or in rare cases, they could be beneficial. The presence of mutagens, such as tobacco smoke or ultraviolet radiation, certainly increases the number of mutations; however, this would not necessarily change the proportion of mutations that affect protein function since such exposures can also cause a rise in neutral or silent mutations.

The percentage of mutations that affect proteins is not likely to be significantly affected by mutagens such as tobacco smoke or ultraviolet radiation. While mutagens can increase the overall number of mutations, the percentage of mutations that affect proteins should remain relatively constant.