Nursing Elites

1. Which of the following is a role of platelets in hemostasis?

• A. formation of plugs
• B. promotion of vasodilation
• C. conversion of prothrombin to thrombin
• D. activation of calcium

Correct answer: A

Rationale: Platelets play a crucial role in hemostasis by forming plugs to stop bleeding. Choice B is incorrect because platelets do not promote vasodilation; instead, they help in vasoconstriction. Choice C is incorrect as the conversion of prothrombin to thrombin is a function of the coagulation cascade involving various clotting factors, not platelets. Choice D is incorrect as platelets do not directly activate calcium; instead, they play a role in the activation of other clotting factors.

2. In negative feedback mechanisms, changes away from the normal state

• A. stimulate changes in the same direction
• B. inhibit all body reactions
• C. stimulate changes in the opposite direction
• D. stimulate a reduction in all body requirements

Correct answer: C

Rationale: In negative feedback mechanisms, changes away from the normal state stimulate changes in the opposite direction. This is a fundamental concept in biological systems where the response to a stimulus opposes the initial change, helping to maintain homeostasis. Choice A is incorrect because negative feedback does not stimulate changes in the same direction. Choice B is incorrect because negative feedback does not inhibit all body reactions, but rather specific responses. Choice D is incorrect because negative feedback does not stimulate a reduction in all body requirements, but rather adjusts specific functions to restore balance.

3. Positive feedback mechanisms usually result in

• A. changes returning values away from a set point.
• B. stable conditions around a set point.
• C. unstable conditions.
• D. long-term changes.

Correct answer: C

Rationale: Positive feedback mechanisms usually result in unstable conditions. In a positive feedback loop, the output enhances or amplifies the changes that are occurring, leading to a deviation from the initial set point. Therefore, positive feedback does not bring values back towards the set point (Choice A). Choice B is incorrect because positive feedback does not promote stability around a set point. Choice D is also incorrect as positive feedback mechanisms typically do not lead to long-term changes; instead, they intensify the initial change, causing instability.

4. Which of the following is a result of stimulation of the sympathetic nervous system?

• A. decreased blood flow to the skeletal muscles
• B. increased cardiac output
• C. decreased respiratory rate
• D. increased urinary output

Correct answer: B

Rationale: Stimulation of the sympathetic nervous system leads to an increase in cardiac output. When the sympathetic nervous system is activated, it causes the heart to beat faster and with more force, leading to an increased cardiac output. Choices A, C, and D are incorrect because the sympathetic nervous system does not cause decreased blood flow to the skeletal muscles, decreased respiratory rate, or increased urinary output.

5. Do we know all there is to know about the structure and function of the human body?

• A. Yes
• B. No
• C. Not Sure
• D. None of the above

Correct answer: B

Rationale: No, the statement that we know all there is to know about the structure and function of the human body is false. The human body is complex, and there is still much to discover and understand about its intricate functions. Science and medicine continue to make new discoveries and advancements in understanding the human body. Choice A is incorrect because it claims that we know everything, which is not true. Choice C is not the best answer as it implies uncertainty rather than acknowledging the ongoing research and discoveries in this field. Choice D is not the correct option as there is a definitive answer to the question.

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