ATI RN
Chapter 14 Nutrition and Fluid Balance Workbook Answers Questions
Question 1 of 5
During states of acidosis and increased H+ secretion by the kidney, which mineral is retained in body fluids?
Correct Answer: B
Rationale: Correct Answer: B (Ca2+) Rationale: In states of acidosis, the body retains Ca2+ in body fluids to help buffer the excess H+ ions and maintain pH balance. Ca2+ acts as a buffer by binding to excess H+ ions, reducing acidity. Kidneys increase Ca2+ retention to counteract the increased H+ secretion. This relationship helps stabilize the body's pH. Summary: A: Na+ is not directly involved in buffering excess H+ ions during acidosis. C: K+ is not specifically retained in response to increased H+ secretion. D: Cl- is not directly related to buffering and pH balance in acidosis.
Question 2 of 5
H+ generated from CO at the tissue level is buffered in transit between the tissues and the lungs primarily by which of the following?
Correct Answer: C
Rationale: The correct answer is C: haemoglobin. Haemoglobin acts as a buffer for H+ generated from CO at the tissue level by binding to the H+ ions, preventing drastic changes in blood pH. Hemoglobin can also release H+ ions when needed, helping to maintain pH balance. A: The HCO3- buffer system primarily buffers H+ generated from CO2 at the tissue level, not from CO. B: The phosphate buffer system mainly functions in the kidneys to regulate blood pH, not in buffering H+ from CO. D: Plasma proteins have a limited role in buffering H+ compared to haemoglobin.
Question 3 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 4 of 5
Which of these conditions could be a cause of respiratory acidosis?
Correct Answer: D
Rationale: Respiratory acidosis occurs when the lungs can't remove enough carbon dioxide, leading to an increase in blood acidity. Emphysema, choice D, a lung condition causing poor air exchange, can result in respiratory acidosis. Aspirin poisoning (choice A) typically causes metabolic acidosis. Severe vomiting (choice B) can lead to metabolic alkalosis due to loss of stomach acid. Severe diarrhea (choice C) can also cause metabolic acidosis from loss of bicarbonate. Therefore, the correct answer is D as it directly affects the respiratory system and can lead to respiratory acidosis.
Question 5 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+].