Nursing Elites

1. T cells in the immune system can be categorized into different types. What type of T cell directly kills infected body cells?

• A. Helper T cells
• B. Cytotoxic T cells
• C. Regulatory T cells
• D. Memory T cells

Correct answer: B

Rationale: Cytotoxic T cells directly kill infected body cells by recognizing specific antigens on the surface of infected cells and releasing cytotoxic substances to induce cell death, eliminating the infected cells. Helper T cells assist in coordinating the immune response, regulatory T cells help maintain immune tolerance, and memory T cells mount a faster and stronger response upon re-exposure to a previously encountered antigen. Therefore, the correct answer is cytotoxic T cells as they play a crucial role in directly targeting and destroying infected cells.

2. How do efferent fibers exit the spinal cord?

• A. Through the anterior aspect
• B. Through the dorsal aspect
• C. Through the ventral aspect
• D. Through the lateral aspect

Correct answer: C

Rationale: Efferent fibers, which carry motor commands, exit the spinal cord through the ventral aspect, also known as the anterior aspect. The correct answer is C, 'Through the ventral aspect.' Efferent fibers exiting through the ventral aspect are responsible for carrying motor commands from the spinal cord to the muscles and glands. Choices A, B, and D are incorrect. Efferent fibers do not exit through the dorsal, lateral, or anterior aspects of the spinal cord.

3. Which of the following does not describe a general trait of macromolecules?

• A. They can exist as single chains.
• B. They can be branched.
• C. They all contain carbon, hydrogen, and phosphorus.
• D. They are all used by the body.

Correct answer: C

Rationale: The correct answer is C. While many macromolecules contain carbon, hydrogen, and phosphorus, not all of them do. For example, lipids, a type of macromolecule, may not contain phosphorus. Choice A and B describe structural features that macromolecules can exhibit, whether as single chains or branched forms. Choice D is incorrect as not all macromolecules are used by the body, such as synthetic polymers or certain non-digestible fibers.

4. Which muscle is the largest in the human body?

• A. Gluteus maximus (buttocks)
• B. Quadriceps femoris (thighs)
• C. Erector spinae (back)
• D. Pectoralis major (chest)

Correct answer: A

Rationale: The correct answer is A, the gluteus maximus (buttocks). The gluteus maximus is indeed the largest muscle in the human body, located at the back of the hip and stretching from the sacrum to the femur. This muscle is crucial for hip joint extension, playing a significant role in various activities such as walking, running, and climbing stairs. Choices B, C, and D are incorrect. While the quadriceps femoris, erector spinae, and pectoralis major are also important muscles, they are not the largest muscle in the human body.

5. What is the purpose of the periosteum, the tough outer layer of bone?

• A. Produces red blood cells
• B. Provides protection and nourishment to bone
• C. Forms the joint surface
• D. Stores minerals

Correct answer: B

Rationale: The periosteum, the tough outer layer of bone, serves the purpose of providing protection to the bone and nourishing it through the blood vessels it contains. It acts as a protective layer for the bone structures. Choices A, C, and D are incorrect because the periosteum does not produce red blood cells (which is the function of bone marrow), form joint surfaces (which is typically the role of articular cartilage), or store minerals (which is primarily done by bone tissue itself and not the periosteum).

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