Nursing Elites

1. Which property describes a substance's resistance to flow?

• A. Density
• B. Viscosity
• C. Conductivity
• D. Reactivity

Correct answer: B

Rationale: Viscosity is the property that describes a substance's resistance to flow. A substance with high viscosity flows slowly, while a substance with low viscosity flows quickly. Density (A) is the measure of mass per unit volume; conductivity (C) is the ability of a material to conduct electricity or heat, and reactivity (D) refers to how readily a substance undergoes chemical reactions. Therefore, the correct answer is B, viscosity, as it directly relates to a substance's resistance to flow.

2. Which bones are included in the axial skeleton?

• A. Head, neck, and trunk
• B. Arms and legs
• C. Hands and feet
• D. All of the above

Correct answer: A

Rationale: The correct answer is A: Head, neck, and trunk. The axial skeleton comprises bones located in the head, neck, and trunk region, such as the skull, vertebral column, and rib cage. These bones provide structural support and protect vital organs like the brain, spinal cord, and heart. Choices B and C are incorrect because arms, legs, hands, and feet are part of the appendicular skeleton, not the axial skeleton. The appendicular skeleton is responsible for movement, manipulation, and mobility, while the axial skeleton primarily provides central support and protection for essential organs.

3. Which feedback loops are less common and sometimes harmful because they enhance stimuli rather than inhibit them?

• A. Negative feedback loop
• B. Positive feedback loop
• C. Inhibitory feedback loop
• D. Stimulating feedback loop

Correct answer: B

Rationale: Correct. Positive feedback loops enhance or amplify changes, which can sometimes be harmful as they drive processes further from equilibrium. In contrast, negative feedback loops work to counteract deviations from a set point, promoting stability. Choice A, 'Negative feedback loop,' is incorrect because negative feedback loops inhibit or reduce changes, promoting stability. Choice C, 'Inhibitory feedback loop,' is incorrect as it is synonymous with negative feedback loops. Choice D, 'Stimulating feedback loop,' is incorrect as it inaccurately describes the nature of positive feedback loops.

4. If a biochemist isolates a large amount of pyruvate, which part of the cell is he working with?

• A. Chloroplasts
• B. Cytoplasm
• C. Mitochondria
• D. Nucleus

Correct answer: B

Rationale: The correct answer is B: Cytoplasm. Pyruvate is a product of glycolysis, a metabolic pathway that takes place in the cytoplasm of the cell. Therefore, a biochemist isolating a large amount of pyruvate would be working with the cytoplasm of the cell. Choice A, Chloroplasts, is incorrect because pyruvate is not produced in chloroplasts, which are responsible for photosynthesis. Choice C, Mitochondria, is incorrect as pyruvate is produced in the cytoplasm before entering the mitochondria for further metabolism. Choice D, Nucleus, is incorrect as the nucleus is not involved in the production or isolation of pyruvate, which is a metabolic intermediate.

5. How do vaccines work?

• A. By directly killing pathogens
• B. By introducing weakened or inactive versions of pathogens to trigger an immune response
• C. By stimulating the immediate production of specific antibodies
• D. None of the above

Correct answer: B

Rationale: Vaccines work by introducing weakened or inactive versions of pathogens to trigger an immune response in the body. This exposure helps the immune system recognize and remember the pathogen, enabling a faster and more effective response upon future exposure. Vaccines do not directly kill pathogens but prepare the immune system for a potential encounter, enhancing protection. They also do not stimulate the immediate production of specific antibodies as the immune response takes time to develop upon vaccination. Choice A is incorrect because vaccines do not kill pathogens directly; they prime the immune system to recognize and respond to them. Choice C is incorrect because while vaccines lead to the production of specific antibodies, it is not immediate, as it takes time for the immune response to develop and produce these antibodies.

Similar Questions