1) One way to prevent bacterial food poisoning is by food irradiation, exposing food to high-energy rays that kill pathogen bacteria. Some think this is a safe way to protect consumers but others think the treatment could produce harmful chemicals.
Irradiated meat, poultry and fruits are now available in many supermarkets. By law, they must be marked with a special symbol. Would seeing this symbol on a package make you more or less likely to purchase the product? Explain your answer.

2) Medieval scientists and philosophers, called alchemists were the predecessors of modern-day chemist. Many of them tried to transform lead (atomic number 82) into gold (atomic number 79). Explain why they never succeed.

3) Prokaryotes have no clearly defined cell nucleus. What other evidences could you look for in trying to determine whether they are cells?

4) Why is it important to maintain a constant chromosome number within a species?

5) The United States is the world’s leading producer and consumer of genetically modified organisms. Some people are uneasy about genetic engineering and would like to avoid products based on this technology. Should food that contains genetically modified plants or livestock be clearly identified on product labels?

6) Nowadays reproductive human cloning is illegal. However, people that are in favor of human cloning claim that it is a solution for organ donors. What are the technical problems of using cloning for donation of organs?

7) Do you have any idea why the incidence of Down Syndrome increases with the mother’s age?

8) A classmate suggests that temperature might affect the rate of mitosis in plant cells. Design an experiment to test this hypothesis.

9) Imagine that you are a genetic engineer. Determine what your next project would be. Then, write up the steps you will follow and what your intended results will be.

10) If a human patient’s bone marrow cells were removed, altered genetically, and re-implanted, would the change be passed on to the patient’s children? Explain your answer.