ATI RN
Chapter 14 Nutrition and Fluid Balance Answer Key Questions
Question 1 of 5
Which tissues in the body contain the lowest percentage of water?
Correct Answer: D
Rationale: The correct answer is D: skeleton. Bones have the lowest percentage of water content compared to other tissues. Bones are composed of minerals, mainly calcium and phosphorus, which make up a significant portion of their structure. Adipose tissue (B) contains a higher percentage of water due to its role in storing fat. Muscle tissue (C) has a moderate water content as it is composed of water, proteins, and other substances. Blood (A) has the highest percentage of water among the choices due to its liquid nature and functions in transportation and circulation.
Question 2 of 5
Which of these statements does NOT refer to the relationship between plasma and interstitial fluid?
Correct Answer: D
Rationale: The correct answer is D because plasma and interstitial fluid are in dynamic equilibrium and do exchange materials through capillary walls. Changing the composition of one affects the other due to this exchange. Choice A is incorrect because plasma and interstitial fluid have some differences. Choice B is incorrect as capillary walls allow for exchange. Choice C is incorrect as proteins are restricted from freely passing through capillary walls.
Question 3 of 5
Which of the following contributes the vast majority of the extracellular fluid's osmotic activity?
Correct Answer: B
Rationale: The correct answer is B: plasma proteins. Plasma proteins contribute the vast majority of extracellular fluid's osmotic activity due to their high concentration and large size, which results in significant osmotic pressure. This osmotic pressure helps maintain fluid balance and regulate the movement of water between compartments. Na+ and its attendant anions (Choice A) are important for fluid balance but do not contribute significantly to osmotic activity. K+ and its attendant anions (Choice C) are mainly intracellular ions and do not play a major role in extracellular osmotic activity. Ca2+ and its attendant anions (Choice D) are essential for various cellular functions but do not contribute significantly to extracellular osmotic activity.
Question 4 of 5
Which of the following will NOT activate the renin-angiotensin-aldosterone system?
Correct Answer: B
Rationale: Correct Answer: B - Decreased K+ in the ECF Rationale: 1. Renin is released by the kidneys in response to decreased arterial blood pressure (A), decreased plasma volume (C), and decreased Na+ in the ECF (D). 2. Aldosterone release is stimulated by decreased plasma volume and decreased Na+ in the ECF, but not by decreased K+ in the ECF. 3. The renin-angiotensin-aldosterone system is primarily involved in regulating Na+ and water balance, not K+ levels. Summary: A, C, and D are incorrect because they can trigger the renin-angiotensin-aldosterone system. Choice B is the correct answer as decreased K+ levels do not directly activate this system.
Question 5 of 5
What will happen if the osmolarity of ECF increases?
Correct Answer: A
Rationale: Step 1: Increased ECF osmolarity causes osmoreceptors to detect the change. Step 2: Osmoreceptors signal the hypothalamus to release ADH (vasopressin). Step 3: ADH increases water reabsorption in the kidneys. Step 4: Water shifts from the ICF into the ECF to restore osmotic balance. Therefore, choice A is correct. Choices B and C are incorrect because changes in osmolarity trigger water movement. Choice D is incorrect because vasopressin secretion would actually increase to help restore water balance.