Question

1. in 1986, a meltdown of a nuclear reactor in the city of chernobyl, in ukraine, released highly radioactive chemicals into the atmosphere. as a result, people suffereed various forms of cancer because of exposure to these radioactive chemicals. cancerous cells divide much more often than noncancerous cells and form tumor in the body. a scientist claims that these cancers were caused by harmful mutations. he wants to make a model to support his claim. which statement best describes what the scientists model needs to represent in order to support his claim? the radioactive chemicals caused structural changes in peoples genes, which changed how proteins functioned in cell division. the radioactive chemicals polluted peoples food, which changed some peoples ability to digest proteins and caused cancer. the radioactive chemicals burned peoples skin, which increased cell division rates in the people who developed cancer. the radioactive chemicals polluted peoples drinking water, which caused cells to divide more quickly in the peoples bodies and form tumors. clear all

Explanation:

Mutations are changes in the DNA sequence. Genes (segments of DNA) code for proteins. If radioactive chemicals cause structural changes (mutations) in genes, it can affect protein function. Since cell division is regulated by proteins, a change in protein function (due to gene mutation) can lead to abnormal cell division (like in cancer). The other options do not address the concept of mutation (change in genes) which is central to the scientist's claim. For example, the option about polluting food and affecting protein digestion is not related to mutation - the key mechanism in the claim. The option about burning skin and increasing cell - division rate does not mention genes. The option about polluting water and causing faster cell division also does not mention genetic mutation.

Answer:

The radioactive chemicals caused structural changes in people's genes, which changed how proteins functioned in cell division.