Nursing Elites

1. What is the fatty substance that coats axons to insulate, protect, and speed up impulses?

• A. Myelin
• B. Dendrite
• C. Neuron
• D. Synapse

Correct answer: A

Rationale: The correct answer is 'Myelin.' Myelin is a fatty substance that functions as an insulator for axons, providing protection and enhancing the speed of electrical impulses along neurons. This insulation is essential for ensuring efficient and rapid communication within the nervous system. Choices B, C, and D are incorrect. Dendrites are branched extensions of a neuron that receive signals, neurons are the basic building blocks of the nervous system that transmit information, and synapses are the junctions between neurons where communication occurs.

2. Which protein complex in the sarcomere is responsible for the thick filament?

• A. Actin
• B. Myosin
• C. Tropomyosin
• D. Troponin

Correct answer: B

Rationale: Myosin is the protein complex responsible for the thick filament in the sarcomere. It interacts with actin, another protein in the sarcomere, to generate the sliding movement that results in muscle contraction. Actin is a thin filament protein that interacts with myosin to create the sliding filament mechanism. Tropomyosin and troponin are regulatory proteins that regulate muscle contraction by controlling the interaction between actin and myosin, rather than directly being responsible for the thick filament.

3. What happens to the frequency of a wave if its wavelength decreases while the speed remains constant?

• A. Frequency decreases
• B. Frequency increases
• C. Frequency remains constant
• D. Frequency becomes zero

Correct answer: B

Rationale: The correct answer is B: Frequency increases. Frequency and wavelength are inversely proportional in a wave with a constant speed. When the wavelength decreases while the speed remains constant, the frequency must increase to maintain the constant speed of the wave. This relationship is governed by the equation: speed = frequency x wavelength. Choice A is incorrect as frequency increases when wavelength decreases. Choice C is incorrect as the frequency changes in this scenario. Choice D is incorrect as the frequency does not become zero but increases when the wavelength decreases.

4. Which of the following sources would be a good starting point that provides the most accurate information for a research project on ancient Persian culture?

• A. The Wikipedia entry on 'Persian Culture'
• B. 'All Cool Persian Stuff,' a blog written by a scientist
• C. 'An Overview of Persian Society,' a book written by a historian
• D. 'Uncovering the Secrets of Persia,' a two-page magazine article about lost temples

Correct answer: C

Rationale: A book written by a historian, such as 'An Overview of Persian Society,' would provide a well-researched and reliable source of information on ancient Persian culture. Choice A, the Wikipedia entry, may contain inaccurate or biased information as it can be edited by anyone. Choice B, a blog by a scientist, may not provide scholarly or comprehensive information on ancient Persian culture. Choice D, a magazine article about lost temples, does not focus on Persian culture as a whole, making it less relevant for a research project specifically on ancient Persian culture.

5. What is the formula for the area of a circle?

• A. A = Ï€r²
• B. A = 2Ï€r
• C. A = Ï€d
• D. A = 2Ï€d

Correct answer: A

Rationale: The correct formula for the area of a circle is A = πr², where π is a mathematical constant approximately equal to 3.14159 and r is the radius of the circle. Choice B, A = 2πr, represents the circumference of a circle, not the area. Choice C, A = πd, incorrectly uses the diameter (d) instead of the radius in the formula for area. Choice D, A = 2πd, is also related to the circumference of the circle, not the area. Therefore, option A is the only correct formula for calculating the area of a circle.

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