Dr. Drew is studying the effect of overexposure to UV radiation in mice. He discovers that mice that are exposed to high levels of UV radiation are much more likely to acquire cancer than mice that are not exposed to UV radiation. Which of the following best explains why high levels of UV radiation can cause cancer in mice?

A. UV radiation can alter an organism's DNA molecules and cause mutations.

B. UV radiation increases the activity level of an organism.

C. UV radiation can cause an organism to have an allergic reaction.

D. UV radiation decreases the amount of food that an organism consumes daily.

the principles and empirical processes of discovery and demonstration considered characteristic of or necessary for scientific investigation, generally involving the observation of phenomena, the formulation of a hypothesis concerning the phenomena, experimentation to test the hypothesis, and development of a conclusion that confirms, rejects, or modifies the hypothesis.

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.