Nursing Elites

1. Homeostasis exists if concentrations of water, nutrients, and oxygen in the body and heat and pressure __________.

• A. decrease steadily
• B. remain within certain limited ranges
• C. increase when the body is stressed
• D. fluctuate greatly between very high and low values

Correct answer: B

Rationale: Homeostasis is the body's ability to maintain stable internal conditions despite external changes. To achieve this balance, concentrations of essential substances must remain within specific ranges. Choice A is incorrect because decreasing concentrations would not maintain stability. Choice C is incorrect as increasing concentrations when the body is stressed would disrupt homeostasis. Choice D is incorrect as fluctuating greatly between high and low values would also not support the body's stability. Therefore, the correct answer is B, as it aligns with the concept of homeostasis by emphasizing the need for stability within certain limits.

2. What do positive feedback mechanisms do?

• A. Cause long-term changes.
• B. Move conditions away from the normal state.
• C. Bring conditions back to the normal state.
• D. Usually produce stable conditions.

Correct answer: B

Rationale: Positive feedback mechanisms amplify or increase changes in a system, moving conditions away from the normal state. This makes choice B the correct answer. Choice A is incorrect as positive feedback does not cause long-term changes but rather accelerates deviations from the norm. Choice C is incorrect because positive feedback does not bring conditions back to normal; instead, it amplifies deviations. Choice D is incorrect as positive feedback does not usually lead to stable conditions but rather to further deviations from the normal state.

3. A parietal layer of a serous membrane lines cavities, whereas a visceral layer of a serous membrane covers organs.

• A. covers organs; lines cavities
• B. lines cavities; covers organs
• C. secretes serous fluid; secretes mucus
• D. secretes mucus; secretes a serous fluid

Correct answer: B

Rationale: In serous membranes, the parietal layer lines the cavities, providing support and protection, while the visceral layer covers the organs, reducing friction and allowing them to move freely. Therefore, the correct answer is 'lines cavities; covers organs.' Choices C and D are incorrect because serous membranes do not secrete mucus; instead, they secrete a watery serous fluid. Choice A is incorrect as it reverses the functions of the parietal and visceral layers in relation to organs and cavities.

4. Is oxygen the primary raw material for new living material?

• A. TRUE
• B. FALSE
• C. Not Sure
• D. None of the above

Correct answer: B

Rationale: While oxygen is essential for many living organisms, it is not the primary raw material for new living material. The primary raw materials for new living material are carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur, collectively known as CHNOPS elements. These elements are the building blocks of biological molecules and are essential for life. Therefore, the correct answer is False. Choices C and D are incorrect because the primary raw materials for new living material are well-established in biology.

5. The transition from a hunter-gatherer to an agricultural lifestyle greatly changed the types of diseases and injuries that early peoples suffered.

• A. True
• B. False
• C. Not Sure
• D. All of the above

Correct answer: A

Rationale: The correct answer is True. The transition from a hunter-gatherer to an agricultural lifestyle did indeed greatly change the types of diseases and injuries that early peoples suffered. With the shift to agriculture came increased sedentism, population density, and interaction with domesticated animals, leading to the emergence of new diseases and health challenges. Choice B is incorrect because the statement is true based on historical and archaeological evidence. Choice C is incorrect as there is historical data supporting the impact of this transition. Choice D is incorrect as it is not applicable since all options do not hold true in this context.

Similar Questions