ATI RN
Chapter 14 Nutrition and Fluid Balance Workbook Answers Questions
Question 1 of 5
If the tubular filtrate becomes too acidic, what is secreted by the tubular epithelial cells to buffer the secreted H+?
Correct Answer: A
Rationale: The correct answer is A: HCO3-. Tubular epithelial cells secrete bicarbonate ions (HCO3-) to buffer the secreted H+ ions. Bicarbonate acts as a base to neutralize the excess acidity in the filtrate. Choice B (OH-) is incorrect because hydroxide ions would only increase the pH, not buffer the acidity. Choice C (NH3) is incorrect because ammonia does not directly buffer acidity. Choice D (NH4+) is incorrect as it is a weak acid and would not effectively buffer the acidity of the filtrate.
Question 2 of 5
The first line of defence against this change in [H+] is the chemical buffer systems. Which primary buffer system will respond to this change?
Correct Answer: A
Rationale: The correct answer is A: phosphate buffer system. Phosphate buffer system is an important intracellular buffer that helps regulate pH within cells. It consists of dihydrogen phosphate (H2PO4-) and monohydrogen phosphate (HPO4^2-). When [H+] increases, H2PO4- can accept H+ ions to form H3PO4, preventing a drastic decrease in pH. Choice B (NH4+:NH3 buffer system) is incorrect because it primarily functions in the kidney to regulate acid-base balance. Choice C (protein buffer system) is incorrect because proteins mainly act as intracellular buffers and have a limited capacity to respond to rapid changes in [H+]. Choice D (haemoglobin buffer system) is incorrect because haemoglobin primarily buffers CO2 levels in the blood through the bicarbonate buffer system, not [H+].
Question 3 of 5
When the ingestion and metabolic synthesis of a substance equals its metabolic utilization and excretion, the body is
Correct Answer: A
Rationale: The correct answer is A. When the ingestion and metabolic synthesis of a substance equal its metabolic utilization and excretion, the body is in a state of balance, known as homeostasis. This means that the body is efficiently utilizing and eliminating the substance to maintain equilibrium. Option B is incorrect because in this scenario, the body is indeed in balance, not in imbalance. Options C and D are also incorrect as they do not provide any relevant information or reasoning. In summary, the correct answer (A) reflects a state of equilibrium in the body's metabolic processes, while the other choices do not accurately describe the situation.
Question 4 of 5
Although the terms "water" and "fluid" are often used to refer to the same thing, they are actually different.
Correct Answer: A
Rationale: The correct answer is A: TRUE. Water and fluid are not interchangeable terms. Water specifically refers to the liquid state of H2O molecules, while fluid is a broader term encompassing any substance that flows and takes the shape of its container. Water is a type of fluid, but not all fluids are water. Therefore, it is accurate to say that water and fluid are different. Summary of Other Choices: B: FALSE - Incorrect because water and fluid have distinct meanings. C: NA - Not applicable as it does not provide a valid response. D: NA - Not applicable as it does not provide a valid response.
Question 5 of 5
Proteins within the ICF are not freely exchanged with the ECF.
Correct Answer: A
Rationale: The correct answer is A: TRUE. Proteins within the intracellular fluid (ICF) are not freely exchanged with the extracellular fluid (ECF) due to the presence of the cell membrane. The cell membrane acts as a semi-permeable barrier that selectively regulates the movement of substances in and out of the cell. Proteins are too large to pass through the cell membrane freely, thus preventing their exchange between the ICF and ECF. This selective permeability is crucial for maintaining the internal environment of the cell and supporting various cellular functions. Option B: FALSE is incorrect because the statement is indeed true, as explained above. Options C and D are not applicable as they do not provide any relevant information to address the question.