Nursing Elites

1. Which type of muscle is characterized by involuntary contractions, is striated, and is primarily found in the heart?

• A. Skeletal muscle
• B. Smooth muscle
• C. Cardiac muscle
• D. Elastic muscle

Correct answer: C

Rationale: The correct answer is C, Cardiac muscle. Cardiac muscle fits the description provided in the question as it exhibits involuntary contractions, striations, and is predominantly located in the heart. Skeletal muscle, while also striated, is voluntary and not involuntary like cardiac muscle. Smooth muscle lacks striations and is typically found in the walls of internal organs. Elastic muscle is not a recognized type of muscle tissue in human anatomy, making it an incorrect choice.

2. As a car accelerates from rest, what happens to its kinetic energy and the work done on it?

• A. Both kinetic energy and work done increase.
• B. Kinetic energy increases, but work done remains constant.
• C. Work done increases, but kinetic energy remains constant.
• D. Both kinetic energy and work done remain constant.

Correct answer: A

Rationale: When a car accelerates from rest, its speed and kinetic energy increase. The work done on the car is what increases its kinetic energy, so both kinetic energy and work done increase simultaneously. Option A is correct because acceleration results in an increase in both kinetic energy and the work done on the car. Option B is incorrect because work done is required to increase kinetic energy during acceleration. Option C is incorrect as work done is directly related to the change in kinetic energy. Option D is incorrect as both kinetic energy and work done increase when the car accelerates.

3. The adrenal cortex produces a group of steroid hormones called corticosteroids. What is a MAJOR function of corticosteroids?

• A. Regulate insulin sensitivity and blood sugar levels
• B. Control blood pressure and electrolyte balance
• C. Stimulate the immune system and inflammatory response
• D. Promote growth and development during puberty

Correct answer: B

Rationale: Corticosteroids, produced by the adrenal cortex, primarily function to control blood pressure and electrolyte balance. One of the key corticosteroids, aldosterone, plays a crucial role in regulating sodium and potassium levels in the body. This regulation is essential for maintaining blood pressure and electrolyte balance. Choices A, C, and D are incorrect because corticosteroids do not primarily regulate insulin sensitivity and blood sugar levels, stimulate the immune system and inflammatory response, or promote growth and development during puberty. While corticosteroids can have effects on insulin sensitivity, immune response, and growth, their major role is in maintaining blood pressure and electrolyte balance.

4. What property of a wave determines the loudness of sound when heard by the human ear?

• A. Frequency
• B. Amplitude
• C. Wavelength
• D. Velocity

Correct answer: B

Rationale: The amplitude of a wave determines the loudness of sound when heard by the human ear. The greater the amplitude of a sound wave, the louder the sound will be perceived. Frequency (Choice A) refers to the number of wave cycles in a given time period. Wavelength (Choice C) is the distance between two corresponding points on a wave. Velocity (Choice D) is the speed at which the wave travels and does not directly affect the loudness of sound perceived by the human ear.

5. What is the general formula for an alkyl halide?

• A. CₙH₂ₙ
• B. CₙH₂ₙ₊₂
• C. CₙH₂ₙ₊₁X
• D. CₙH₂ₙO

Correct answer: C

Rationale: The correct answer is option C, 'CₙH₂ₙ₊₁X.' This is the general formula for an alkyl halide, where X represents a halogen atom (such as fluorine, chlorine, bromine, or iodine), and the hydrocarbon chain is represented by CₙH₂ₙ₊₁. Option A, 'CₙH₂ₙ,' is incorrect because it does not account for the presence of a halogen atom. Option B, 'CₙH₂ₙ₊₂,' is incorrect as it represents an alkene, not an alkyl halide. Option D, 'CₙH₂ₙO,' is also incorrect as it suggests the presence of oxygen, which is not characteristic of alkyl halides.

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