The way in which some organism supplies some other organism with food and energy known as

Correct Answer: A

Rationale: The correct answer is A: Food chains. A food chain depicts the flow of energy and nutrients from one organism to another in an ecosystem. It shows how energy is transferred from producers to consumers. Food network (B) is a more complex and interconnected system than a simple linear chain. Pyramid of power (C) represents the energy flow in an ecosystem, not the transfer of food. Levels of nutrition (D) is not a term commonly used to describe how organisms transfer food and energy.

Correct Answer: C

Rationale: Rationale: 1. Clonal selection theory states that specific lymphocytes are activated by antigens. 2. Upon activation, these lymphocytes proliferate to form a clone of cells specific to the antigen. 3. This increases the number of lymphocytes specific for the antigen. 4. Choice C correctly aligns with the essence of clonal selection theory. Summary: A: Incorrect - Clonal selection theory does not involve a single lymphocyte expressing multiple antigen receptors. B: Incorrect - Antigens do not influence the generation of antigen receptors, but rather activate specific lymphocytes. D: Incorrect - Clonal selection theory focuses on lymphocyte response to antigens, not neutrophil increase during infections.

Correct Answer: C

Rationale: TLR-3 detects viruses in endosomes. When a virus enters a host cell, it is often engulfed into endosomes. TLR-3 recognizes viral RNA within endosomes and triggers an immune response. Choices A and B are incorrect because TLR-3 does not detect viruses in the cytosol or extracellular space. Choice D is incorrect because TLR-3 specifically functions in endosomes to detect viral RNA.

Correct Answer: C

Rationale: The correct answer is C because pathogens are microorganisms that specifically cause disease in a host with normal immune functions. Pathogens have mechanisms to evade or overcome the host's immune system, leading to the development of diseases. Choices A and B are characteristics of both pathogens and non-pathogenic organisms. Choice D is incorrect because not all pathogens are transmitted between individuals of the same species; some pathogens can be transmitted from animals to humans or through environmental sources.

Correct Answer: B

Rationale: The correct answer is B. Herd immunity refers to the protection offered to non-immunized individuals when a high percentage of the population is immunized, preventing the pathogen from spreading easily. This is because when a large portion of the population is immune to a disease, it creates a barrier that reduces the overall transmission of the pathogen, thus protecting those who are not vaccinated or cannot be vaccinated. Choice A is incorrect because herd immunity is not solely about the total number of immunized individuals, but rather about the impact on the entire population. Choice C is incorrect as it refers to the efficacy of the vaccine in generating a protective response, not the concept of herd immunity. Choice D is incorrect as it relates to social influence rather than the collective protection provided by high rates of immunization.