This set of Cell Biology Multiple Choice Questions & Answers (MCQs) focuses on “Cancer – Causes”.
1. When was it discovered that there is a correlation between cancer and the environment?
Explanation: It was first discovered in 1775 by a British surgeon, Percivall Pott, that an environmental agent is related to the development of cancer. He concluded that due to chronic exposure to soot, there is high incidence of cancer of the nasal cavity and the skin of scrotum.
2. Which of the following is not a DNA tumor virus?
d) Polyoma virus
Explanation: The viruses that can infect mammalian cells growing in culture and transform them into cancer cells, are divided into two categories – DNA viruses and RNA viruses, depending on the type of nucleic acid found within the mature viral particle. Human immunodeficiency virus (HIV) has a structure similar to RNA viruses.
3. Certain agents may be converted to mutagenic compounds by the action of cellular enzymes.
Explanation: Certain agents or environmental factors such as harmful rays, smoke from industries etc. may not act as mutagens themselves. But, once they gain entry in the body, a conversion to mutagenic form might occur by the action of cellular enzymes.
4. Which of the following virus is associated with Kaposi’s sarcoma?
b) Hepatitis virus
d) Epstein-Barr virus
Explanation: Kaposi’s sarcoma is a type of cancer in which patches of abnormal tissue grow under the skin. Herpes virus (HHV-8) is associated with the Kaposi’s sarcoma. The formal name of HHV according to International Committee on Taxonomy of Viruses is Human gammaherpesvirus 8.
5. When the levels of glucose drop, alpha-cells in the pancreas secrete ____________________
d) pancreatic fluid
Explanation: When the glucose levels drop, alpha cells in the pancreas secrete glucagon in an effort to maintain the glucose levels. The glucagon acts through G-protein coupled receptor and stimulates the breakdown of glycogen.
6. Which of the following is a stomach-dwelling bacterium?
a) Helicobacter pylori
b) Staphylococcus epidermis
c) Staphylococcus hominis
Explanation: Helicobacter pylori is a stomach-dwelling bacterium, chronic infection of which can lead to gastric lymphomas and stomach ulcers. Helicobacter pylori was previously known as Campylocater pylori.
7. Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce the risk of __________________
a) Colon cancer
b) Breast cancer
Explanation: Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs), for example, aspirin and indomethacin can decrease the risk of colon cancer. NSAIDs can evoke this effect by inhibiting an enzyme – cyclooxygenase-2.
8. Cyclooxygenase-2 synthesizes _____________________
Explanation: Cyclooxygenase-2 is the enzyme that synthesizes hormone-like prostaglandins that promote the growth of intestinal polyps. Polyps are abnormal tissue growths that look like flat bumps.
Sanfoundry Global Education & Learning Series – Cell Biology.
To practice all areas of Cell Biology, here is complete set of 1000+ Multiple Choice Questions and Answers.