Question

students are studying how mutations in dna that result from external factors called mutagens can affect consider changes that happen to dna and the possible causes of those mutations. which three statements describe how mutations in dna can occur? a. radiation from the sun alters the dna coding, which results in a new trait in the organism. b. radiation from the sun alters cell structure, which results in a new dna code and new, abnormal traits. c. inhalation of chemical pollutants in the air alters cell respiration, which produces a new, abnormal protein. d. exposure to chemical pollutants alters the base sequences in dna, which introduces a new, abnormal trait in the e. carcinogenic compounds in cigarettes alter amino acid sequences, which introduces a new, abnormal protein in

Explanation:

• Option A: Sun radiation (a mutagen) can alter DNA coding, leading to new traits. This is a valid way mutations occur.
• Option B: Mutagens like sun radiation affect DNA, not directly cell structure to change DNA. So B is incorrect.
• Option C: Inhalation of pollutants altering cell respiration doesn't directly cause DNA mutation (it affects respiration, not DNA base sequences). So C is incorrect.
• Option D: Chemical pollutants (mutagens) can alter DNA base sequences, leading to abnormal traits. This is correct.
• Option E: Carcinogenic compounds in cigarettes can alter DNA (which then affects amino acid sequences via transcription/translation), introducing abnormal proteins. This is a valid mutation pathway.

So the three correct statements are A, D, E.

Answer:

A. Radiation from the Sun alters the DNA coding, which results in a new trait in the organism.
D. Exposure to chemical pollutants alters the base sequences in DNA, which introduces a new, abnormal trait in the
E. Carcinogenic compounds in cigarettes alter amino acid sequences, which introduces a new, abnormal protein in