Nursing Elites

1. Glial cells support and protect neurons within the central and peripheral nervous system. What are they called?

• A. Astrocytes
• B. Neuroglia
• C. Oligodendrocytes
• D. Schwann cells

Correct answer: A

Rationale: Astrocytes are a type of glial cell that provide support and protection for neurons in both the central and peripheral nervous systems. While the term 'Neuroglia' is often used to refer to glial cells collectively, in this context, the question specifically asks for the name of the cells, making 'Astrocytes' the correct answer. Choice B, 'Neuroglia,' is a general term for all glial cells, not a specific type. Choices C and D, 'Oligodendrocytes' and 'Schwann cells,' are also types of glial cells but are not the primary cells responsible for supporting and protecting neurons as described in the question.

2. What is the term for the first exposure to a specific pathogen, leading to the development of an initial immune response?

• A. Primary immune response
• B. Secondary immune response
• C. Hypersensitivity reaction
• D. Immunological tolerance

Correct answer: A

Rationale: The correct answer is A: Primary immune response. The primary immune response refers to the initial encounter with a specific pathogen, which triggers the development of the first immune response by the immune system. This response involves activating immune cells like B cells and T cells to produce antibodies and memory cells specific to that pathogen. On the other hand, the secondary immune response occurs upon re-exposure to the same pathogen and is characterized by a faster, stronger, and more effective immune response due to the presence of memory cells from the primary response. Choices B, C, and D are incorrect. The secondary immune response is the response upon re-exposure, hypersensitivity reactions are exaggerated immune responses to antigens, and immunological tolerance is the immune system's ability to recognize and tolerate self-antigens without mounting an immune response.

3. Why are elements in Group 18 (Noble gases) generally unreactive?

• A. They have high atomic masses
• B. They lack valence electrons
• C. Their outermost electron shells are completely filled
• D. They exist as single atoms, not molecules

Correct answer: C

Rationale: Elements in Group 18 (Noble gases) are generally unreactive because their outermost electron shells are completely filled. This results in high stability and low reactivity since they have achieved a full valence shell configuration, making them less likely to gain, lose, or share electrons with other atoms. The full valence shell configuration leads to a minimal tendency for these elements to form chemical bonds, hence exhibiting low reactivity. Choices A, B, and D are incorrect because high atomic masses, lack of valence electrons, and existing as single atoms do not directly contribute to the unreactivity of noble gases. It is the full valence shell configuration that is the primary reason for their inert nature.

4. What is the neural pathway that triggers a reflex action?

• A. Reflex loop
• B. Reflex arc
• C. Neural pathway
• D. Reflex reaction

Correct answer: B

Rationale: The correct answer is 'B: Reflex arc.' A reflex arc is the neural pathway that triggers an automatic, involuntary reflex action in response to a stimulus. It involves sensory neurons, interneurons in the spinal cord, and motor neurons, allowing for a rapid response without conscious thought. Choice A, 'Reflex loop,' is incorrect as the term commonly used is 'Reflex arc' to describe this neural pathway. Choice C, 'Neural pathway,' is too general and does not specifically refer to the pathway involved in reflex actions. Choice D, 'Reflex reaction,' is not the commonly accepted term to describe the neural pathway that triggers reflex actions.

5. Which term describes a substance's ability to undergo a change that transforms it into a different substance?

• A. Density
• B. Mass
• C. Reactivity
• D. Volume

Correct answer: C

Rationale: Reactivity refers to a substance's ability to undergo a change that transforms it into a different substance through a chemical reaction. In this context, reactivity specifically refers to the chemical behavior of a substance. Density, mass, and volume are physical properties of a substance and do not describe its ability to undergo a chemical change. Density is the mass per unit volume, mass is the amount of matter in an object, and volume is the amount of space occupied by an object. Therefore, reactivity is the most appropriate term to describe a substance's ability to undergo a transformation into a different substance.

Similar Questions