The nurse determines that a patient has long-term immunity against a disease. Which part of the immune system should the nurse recognize is responsible for this patient's long-term immunity?

Correct Answer: B

Rationale: The correct answer is B: IgG. IgG is an immunoglobulin that provides long-term immunity by recognizing and neutralizing pathogens. It is produced by plasma cells in response to an infection, allowing the body to remember the pathogen and mount a quicker and more effective immune response upon re-exposure. IgE is involved in allergic reactions, not long-term immunity. Mast cells are involved in allergic responses and inflammation, not long-term immunity. Plasma cells produce antibodies, including IgG, but the plasma cells themselves are not responsible for long-term immunity.

Correct Answer: B

Rationale: The correct answer is B: thylakoid membranes within chloroplasts. Prokaryotic cells lack membrane-bound organelles like chloroplasts, where thylakoid membranes are found. This is a key feature of prokaryotic cells. Choices A, C, and D are characteristics that can occur in prokaryotic cells. Cellular organization is present in prokaryotic cells, oxygenic photosynthesis can be carried out by some prokaryotic organisms, and prokaryotic cells can perform anaerobic respiration.

Correct Answer: B

Rationale: The correct answer is B: more enveloped forms. This trend can be explained by the complexity of host organisms. Bacteria have simple cell structures, making enveloped viruses less common. As we move from bacteria to plants and vertebrate animals, the complexity of host cells increases, leading to a higher prevalence of enveloped viruses. This trend is due to the need for enveloped viruses to evade the host's immune system and facilitate entry into host cells. Choices A, C, and D are incorrect because they do not consider the relationship between virus structure and host complexity.

Correct Answer: B

Rationale: The correct answer is B: propionic acid, carbon dioxide. Propionic acid is produced by bacteria in Swiss cheese, contributing to its nutty flavor. The bacteria also produce carbon dioxide, which forms the characteristic holes. Lactate (A) is a byproduct of bacteria in cheese but not responsible for the flavor or holes. Acetic acid (C) is not commonly found in Swiss cheese. Ethanol (D) and hydrogen are not involved in the flavor or hole formation.

Correct Answer: D

Rationale: The correct answer is D: Saliva. Saliva has very low levels of HIV, making it least likely to transmit AIDS. HIV transmission requires direct contact with infected bodily fluids containing high viral loads, such as blood, breast milk, and semen. Saliva does not typically contain enough HIV to transmit the virus, as it has enzymes that can inhibit HIV. Therefore, the risk of HIV transmission through saliva is extremely low compared to the other fluids listed.