Malignant tumors are sometimes treated with drugs that halt mitosis, and thus stop the production of new cancer cells. Two such drugs, vincristine sulfate and vinblastine sulfate, interfere with the formation of spindle fibers. How could this action halt mitosis? Antibiotics such as mitomycin C and inorganic compounds such as cis-platinum also can be used to stop the growth of tumors. These drugs interfere with DNA synthesis in treated cells. How could this action halt mitosis?

Propose ideas for the development of drugs that could stop viral replication cycles.

During your shift at the clinic, a young man arrives with a red, scaly rash formed into rings. What is this patient’s diagnosis likely to be? What causes this condition? How can he avoid this rash in the future?

The cancer drug vinblastine interferes with synthesis of microtubules. In mitosis, this would interfere with what? A. spindle formation, B. DNA replication, C. carbohydrate synthesis, D. disappearance of the nuclear envelope.

Based on what you have learned about cancer and chemotherapy. explain why you think cancer patients who are treated with chemotherapy drugs can lose their hair.