Abnormal chromosomes are frequently found in malignant tumors. Errors such as translocations may place a gene in close proximity
to different control regions. Which of the following might then occur to make the cancer worse? A) an increase in nondisjunction B) expression of inappropriate gene products C) a decrease in mitotic frequency D) death of the cancer cells in the tumor
Most of the cancers are caused when a normal gene that code for one or other proteins involved in the regulation of the cell cycle is mutated. The mutated gene may cause the production of the faulty gene products. For example, the overproduction of products of the protooncogene that push cells through the cell cycle leads to tumor formation. Likewise, when the tumor suppressor genes are not able to produce enough product to prevent progression through the cell cycle, cancer may develop.
