C. Pollution initially decreases, then increases the biodiversity in an ecosystem. D. Pollution has no effect on the biodiversity of ecosystems. Questions 5-8 are based on this passage and figure. For years, scientists debated whether hereditary information was contained in protein or in nucleic acids. One experiment, performed in the early 1950s helped answer this question.
Protein contains sulfur, but very little phosphorus.
DNA contains phosphorus, but very little sulfur. To determine if protein or DNA is the genetic material, scientists cultured viruses that incorporated either radioactive sulfur or radioactive phosphorus. After a given time, radioactive phosphorus appeared within the bacteria. It was contained within viral DNA that was genetically identical to the DNA of the viruses that initiated the infection. Radioactive sulfur remained outside of the bacteria.