Mature naïve T cells that leave the thymus

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: 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.

Correct Answer: B

Rationale: The correct answer is B because modern immunology indeed builds on the groundbreaking contributions of scientists like Jenner and Pasteur. Their work laid the foundation for understanding concepts like vaccination and immune responses. Choice A is incorrect because modern immunology encompasses both innate and adaptive immunity. Choice C is incorrect as immunology extends beyond tissue healing to include immune responses to pathogens and self-cells. Choice D is incorrect as immunology is a rapidly evolving field with significant advancements in understanding immune mechanisms and developing new treatments.

Correct Answer: B

Rationale: The correct answer is B because hosts developing epigenetic changes for immune adaptation is a significant consequence of the evolutionary arms race between hosts and pathogens. This adaptation allows hosts to better defend against evolving pathogens over time. This process is dynamic, as both hosts and pathogens continuously evolve in response to each other. Choice A is incorrect because pathogens can evolve rapidly to adapt to host defenses. Choice C is incorrect because while hosts may have mutations that provide advantages, pathogens can also evolve to overcome host defenses. Choice D is incorrect as the interaction between hosts and pathogens is characterized by constant adaptation and change, not remaining static.