Identify the incorrect statement in regard to immunoglobulins (Ig)

Correct Answer: B

Rationale: The correct answer is B because immunoglobulins can indeed recognize conformational antigens on viral particles. Immunoglobulins have variable regions that can bind to a wide range of antigen shapes. Choice A is correct as Ig structure consists of two light and two heavy chains. Choice C is incorrect as immunoglobulins can also bind to internal epitopes. Choice D is incorrect as Ig expression starts during the late B cell development stage.

Correct Answer: B

Rationale: The correct answer is B because mature naïve T cells that leave the thymus can include self-reactive T cells that have not been tolerized against a specific antigen. This is because the process of negative selection in the thymus eliminates most self-reactive T cells but does not catch all of them. Some self-reactive T cells may escape negative selection and circulate as mature naïve T cells. Therefore, it is possible for mature naïve T cells leaving the thymus to include self-reactive T cells that have not been tolerized against a specific antigen. Choices: A: This is incorrect because although negative selection in the thymus eliminates most self-reactive T cells, it does not catch all of them, so some self-reactive T cells may still be present in the mature naïve T cell population. C: This is incorrect because mature naïve T cells already have the ability to recognize antigens presented by MHC, which is developed in the th

Correct Answer: D

Rationale: The correct answer is D, "All of the above A, B, and C". Step 1: Induction of a neutralizing antibody response (A) is crucial as it helps prevent the virus from infecting cells. Step 2: Induction of a cytotoxic T cell response (B) is important to eliminate infected cells and stop the spread of the virus. Step 3: Protection against multiple strains (C) is desirable to ensure broad coverage against different flu strains. Combining A, B, and C in a vaccine would provide comprehensive protection against the flu by targeting different aspects of the immune response. Choices A, B, and C are incorrect individually as they each address only one aspect of a desirable flu vaccine, whereas the correct answer D encompasses all three crucial features.

Correct Answer: C

Rationale: The correct answer is C: Increasing pathogen reproduction. The immune system's main function is to protect the body from pathogens and foreign invaders, not to promote their reproduction. A: Promoting wound healing is correct as the immune system helps in tissue repair. B: Fighting cancer is correct as the immune system plays a role in recognizing and destroying cancerous cells. D: Eliminating cell debris is correct as the immune system helps in clearing out dead or damaged cells to maintain tissue health.

Correct Answer: B

Rationale: The correct answer is B: Dendritic cells. Dendritic cells are sentinel cells in tissues that detect pathogens and activate the immune response. They are crucial in initiating adaptive immune responses by presenting antigens to T cells. T lymphocytes (A) are involved in adaptive immunity, not innate immunity. B lymphocytes (C) mature into plasma cells (D) which produce antibodies, but they are not sentinel cells in tissues like dendritic cells.