Nursing Elites

1. Which of the following correctly identifies a difference between the primary and secondary immune response?

• A. In the secondary response, macrophages migrate to the lymph nodes to present the foreign microorganism to helper T lymphocytes.
• B. The humoral immunity that characterizes the primary response is coordinated by B lymphocytes.
• C. The primary response is quicker and more powerful than the secondary response.
• D. Suppressor T cells are activated in the secondary response to prevent an overactive immune response.

Correct answer: C

Rationale: The correct answer is C. The primary immune response is slower and less powerful compared to the secondary immune response. During the primary response, immune cells encounter the antigen for the first time, necessitating the activation and proliferation of specific immune cells. In contrast, the secondary response benefits from memory cells that quickly recognize the antigen, enabling a faster and more potent immune response. Choices A, B, and D are incorrect. While macrophages play a role in presenting antigens to T cells, this is not a defining difference between primary and secondary responses. Humoral immunity involves B lymphocytes in both primary and secondary responses, so it does not differentiate the two. Suppressor T cells primarily function to regulate the immune response but are not a key factor distinguishing primary from secondary responses.

2. Which of the following is the main organ responsible for absorbing nutrients?

• A. Stomach
• B. Small intestine
• C. Large intestine
• D. Pancreas

Correct answer: B

Rationale: The small intestine is the main organ responsible for absorbing nutrients from the food we eat. It is where the majority of digestion and absorption of nutrients such as carbohydrates, proteins, fats, vitamins, and minerals occurs. The inner lining of the small intestine is covered in tiny finger-like projections called villi, which increase the surface area available for nutrient absorption. While the stomach plays a role in breaking down food into smaller particles, the actual absorption of nutrients primarily takes place in the small intestine. The large intestine mainly absorbs water and electrolytes, and the pancreas produces digestive enzymes and hormones but is not primarily responsible for absorbing nutrients.

3. Which of the following is an example of a zoonotic disease?

• A. The common cold
• B. Influenza (the flu)
• C. Malaria
• D. HIV/AIDS

Correct answer: B

Rationale: A zoonotic disease is a disease that can be transmitted from animals to humans. Influenza is an example of a zoonotic disease as it can be transmitted from animals such as birds and pigs to humans. The common cold (option A) is caused by human rhinoviruses and is not considered a zoonotic disease. Malaria (option C) is transmitted through the bite of infected mosquitoes and is not considered a zoonotic disease. HIV/AIDS (option D) is caused by the human immunodeficiency virus and is not considered a zoonotic disease.

4. What phenomenon explains the bending of light as it passes around an obstacle or through an aperture?

• A. Refraction
• B. Reflection
• C. Diffraction
• D. Dispersion

Correct answer: C

Rationale: Diffraction is the phenomenon that explains the bending of light as it passes around an obstacle or through an aperture. When light encounters an obstacle or passes through an aperture, it diffracts, causing it to bend around the edges. Refraction, on the other hand, occurs when light passes from one medium to another, causing it to change direction. Reflection involves the bouncing back of light rays from a surface, and dispersion is the separation of light into its different colors. Therefore, the correct answer is C, as diffraction specifically addresses the bending of light as it interacts with obstacles or apertures, unlike the other choices that describe different optical phenomena.

5. During which of the following stages does crossing over occur?

• A. Mitosis Prophase
• B. Meiosis Prophase I
• C. Meiosis Prophase II
• D. Interphase

Correct answer: B

Rationale: Crossing over occurs during Prophase I of meiosis. This stage is specifically associated with genetic recombination, where homologous chromosomes exchange genetic material. This process contributes to genetic diversity by creating new combinations of alleles. Choices A, C, and D are incorrect. In mitosis, crossing over does not occur as it involves the separation of replicated chromosomes. Meiosis Prophase II is focused on the reformation of nuclei and does not involve crossing over. Interphase is a stage where the cell prepares for division and is not associated with crossing over.

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