墨尔本PTE 阅读排序 2967

A. Carcinogens are chemicals that can damage DNA and interfere with a cell‘s normal cycle, thus disrupting the cells ability to control when and how often it divides.   

B. Cancer cells are the exception, these cells do not die and divide uncontrollably as they crowd out healthy, productive cells.   

C. Cells do not live forever, and they will reach a point where they will divide through mitosis, or die through a process called apoptosis.   

D. Cancer can have many causes, but most are thought to be related to carcinogens in the environment.