Nursing Elites

1. Which neurotransmitter is responsible for stimulating muscle contraction?

• A. Dopamine
• B. Acetylcholine
• C. Serotonin
• D. Norepinephrine

Correct answer: B

Rationale: Acetylcholine is the neurotransmitter responsible for stimulating muscle contraction at the neuromuscular junction. When an action potential reaches the end of a motor neuron, acetylcholine is released into the synaptic cleft and binds to receptors on the muscle cell membrane, leading to muscle contraction. Dopamine, serotonin, and norepinephrine are neurotransmitters that have different functions in the nervous system and are not directly involved in stimulating muscle contraction. Dopamine is involved in reward and pleasure pathways, serotonin regulates mood and behavior, and norepinephrine is involved in the 'fight or flight' response.

2. What happens to the work done on an object when the angle between the force and displacement is 90 degrees?

• A. Maximum work is done
• B. No work is done
• C. Minimum work is done
• D. Work is infinite

Correct answer: B

Rationale: When the angle between the force and displacement is 90 degrees, the work done is given by the formula W = F * d * cos(theta), where theta is the angle between the force and displacement vectors. Since cos(90 degrees) = 0, the work done becomes zero. This means that no work is done on the object when the angle between the force and displacement is 90 degrees. Choice A is incorrect because maximum work is done when the force and displacement are in the same direction (theta = 0 degrees). Choice C is incorrect as minimum work is done when the force and displacement are parallel (theta = 0 degrees), not perpendicular. Choice D is incorrect because work cannot be infinite; it depends on the force, displacement, and the cosine of the angle between them.

3. Why do emerging infectious diseases (EIDs) pose a significant public health threat?

• A. Because they are well-understood by medical professionals
• B. Because they are easily treatable with existing antibiotics
• C. Because they are new, rapidly evolving, and can spread quickly
• D. Because they primarily affect animals and not humans

Correct answer: C

Rationale: Emerging infectious diseases (EIDs) are a significant public health threat because they are characterized by being new or newly identified diseases that are rapidly evolving. These diseases can spread quickly within populations due to factors such as globalization, travel, urbanization, and changes in climate. EIDs often present challenges to medical professionals as they may not be well-understood initially, making it difficult to develop effective treatments or preventive measures. While some EIDs can be treatable with existing antibiotics, the rapid evolution of these diseases can lead to the development of drug resistance, further complicating treatment efforts. Additionally, EIDs are not limited to affecting animals; they can also have serious implications for human health and well-being. Therefore, the correct answer is that EIDs pose a threat because they are new, rapidly evolving, and can spread quickly. Choices A, B, and D are incorrect because EIDs are not well-understood initially, may develop drug resistance, and can affect humans significantly, not just animals.

4. Through what tubes does urine travel from the kidneys to the bladder?

• A. Urethra
• B. Ureters
• C. Renal arteries
• D. Renal veins

Correct answer: B

Rationale: The correct answer is 'Ureters.' The ureters are the tubes that transport urine from the kidneys to the bladder. The urethra, not a choice in this question, is the tube responsible for carrying urine from the bladder out of the body. Renal arteries and veins are blood vessels that respectively supply and drain the kidneys, not involved in the transport of urine to the bladder.

5. In the context of the cardiac cycle, what does the P wave on an electrocardiogram (ECG) represent?

• A. Atrial depolarization
• B. Ventricular depolarization
• C. Atrial repolarization
• D. Ventricular repolarization

Correct answer: A

Rationale: The P wave on an electrocardiogram (ECG) represents atrial depolarization, which signifies the electrical activation of the atria as they prepare to contract. During the cardiac cycle, atrial depolarization occurs first, leading to atrial contraction. Ventricular depolarization is represented by the QRS complex, not the P wave. Choices B, C, and D are incorrect because the P wave specifically corresponds to atrial depolarization, not ventricular depolarization, atrial repolarization, or ventricular repolarization.

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