Which of the statements below is NOT true. Integration is a stage of HIV life cycle that

Correct Answer: A

Rationale: The correct answer is A. Integration is a stage of HIV life cycle that involves the insertion of viral DNA into the host cell's genome, facilitated by the enzyme integrase. To explain why A is incorrect, integrase is a viral enzyme, not a host enzyme. B is correct as some anti-HIV drugs target the integration stage to prevent viral replication. C is correct as integrated proviral DNA allows for duplication during cell division. D is correct as integration requires the formation of double-stranded viral DNA.

Correct Answer: C

Rationale: The correct answer is C: IFN-alpha. This is because IFN-alpha belongs to the interferon family, not the interleukin family. Interleukins are a subset of cytokines that are primarily involved in regulating immune responses, while interferons have antiviral properties. IL-1, IL-22, and IL-10 are all interleukins and are part of the interleukin family. Therefore, IFN-alpha is the only cytokine listed that is not included in the interleukin family.

Correct Answer: B

Rationale: The correct answer is B: Fighting cancer by targeting abnormal cells. The immune system plays a crucial role in cancer by identifying and eliminating abnormal cells that can develop into tumors. This process is known as immunosurveillance. Through mechanisms like T cells and natural killer cells, the immune system can detect and destroy cancerous cells before they can grow and spread. This function is essential in preventing the development and progression of cancer. Choices A, C, and D are incorrect: A: Promoting cell growth - The immune system does not promote cell growth in cancer; rather, it regulates and suppresses the growth of abnormal cells. C: Enhancing pathogen resistance - While the immune system does enhance resistance against pathogens, this is not its critical function in cancer. D: Stimulating autoimmune responses - Autoimmune responses involve the immune system attacking healthy cells, not targeting cancerous cells.

Correct Answer: A

Rationale: Louis Pasteur is credited with introducing the germ theory of disease. He conducted experiments that demonstrated the role of microorganisms in causing infections. He also developed pasteurization to kill harmful bacteria in food and beverages. Edward Jenner is known for developing the smallpox vaccine, not the germ theory. Elie Metchnikoff studied the immune system and phagocytosis. Paul Ehrlich is known for his work on chemotherapy and the concept of the "magic bullet," targeting specific pathogens.

Correct Answer: B

Rationale: The correct answer is B - Macrophages and neutrophils are the most important phagocytes in innate immunity. Macrophages are versatile cells that engulf and destroy pathogens, while neutrophils are the most abundant phagocytes in the blood and are critical for early immune responses. Natural killer cells and B lymphocytes (A) are not phagocytes, but rather involved in adaptive immunity. T cells and dendritic cells (C) play roles in adaptive immunity and antigen presentation, not direct phagocytosis. Basophils and eosinophils (D) are involved in allergic reactions and parasitic infections, not primary phagocytic functions.