Answer to Question 1
Correct Answer: 2,3,4,5
Rationale 1: Malignant tumors are rapidly growing.
Rationale 2: Malignant tumors are invasive.
Rationale 3: Malignant tumors can be lethal if left untreated.
Rationale 4: Malignant tumors are often classified as carcinomas.
Rationale 5: Malignant tumors are often classified as sarcomas.
Global Rationale: Whereas benign tumors are usually slow growing, remain localized, and rarely cause death, malignant tumors are rapidly growing, invasive, and will kill the host if left untreated. Malignant tumors are classified as carcinomas or sarcomas.
Answer to Question 2
Correct Answer: 1
Rationale 1: Cancer is thought to result from damage to the genes that control cell growth.
Rationale 2: Viruses are associated with only about 15 of all human cancers.
Rationale 3: Some cancer is genetic, but this is not the best answer.
Rationale 4: Cigarette smoking and secondhand smoke are carcinogens that can lead to the development of cancer, but this is not the best answer.
Global Rationale: Cancer is thought to result from damage to the genes controlling cell growth. Once damaged, cells may become unresponsive to the chemical signals that normally check growth. The cancer cells lose their normal functions, dividing rapidly and invading surrounding tissues. Viruses are associated with only about 15 of all human cancers. Some cancer is genetic, but this is not the best answer. Cigarette smoking and secondhand smoke are carcinogens that can lead to the development of cancer, but this is not the best answer.