The absorption of fructose by intestinal mucosa is
- A. co- transport mechanism
- B. simple diffusion
- C. facilitated transport
- D. active transport
Correct Answer: C
Rationale: The correct answer is C: facilitated transport. Fructose is absorbed through facilitated diffusion using specific carrier proteins in the intestinal mucosa. This process does not require energy input and allows fructose to move down its concentration gradient. Unlike active transport (requiring energy) and co-transport mechanisms (involving multiple substances), fructose absorption occurs through facilitated transport by specific carrier proteins. Simple diffusion is not the main mechanism for fructose absorption due to its hydrophilic nature. Thus, facilitated transport best describes how fructose is absorbed by the intestinal mucosa.
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What is the best advice for a patient with an ostomy regarding skin care?
- A. Avoid using skin barrier products, as they can cause irritation.
- B. Use a mild soap and water to clean the skin around the stoma.
- C. Only clean the stoma with alcohol wipes.
- D. Change the ostomy appliance every 24 hours.
Correct Answer: B
Rationale: The correct answer is B: Use a mild soap and water to clean the skin around the stoma. This is because gentle cleansing helps prevent skin irritation and infection. Cleaning with harsh products can damage the skin. Choice A is incorrect because skin barrier products are essential for protecting the skin. Choice C is incorrect as alcohol wipes can be too harsh and drying for the skin. Choice D is incorrect because ostomy appliances typically do not need to be changed daily unless there are specific issues.
The pacemaker signal generated by the SA node spreads to the ventricles by passing through the AV node. What would happen to the contraction of the ventricles if there was a complete block at the AV node?
- A. the ventricles would cease beating
- B. the ventricles would beat very fast and uncontrollably
- C. the ventricles would contract rhythmically, but more slowly
- D. the ventricles would contract at the same rate as the atria
Correct Answer: C
Rationale: Rationale: A complete block at the AV node would prevent the transmission of the pacemaker signal from the SA node to the ventricles. As a result, the ventricles would not receive the signal to contract at their normal rate. Instead, they would rely on their inherent ability to generate impulses, resulting in a slower, but still rhythmic contraction. This scenario is known as an escape rhythm, where a lower pacemaker takes over in the absence of the SA node signal.
Summary:
A: the ventricles would cease beating - Incorrect, as the ventricles have their own intrinsic pacemaker.
B: the ventricles would beat very fast and uncontrollably - Incorrect, as a complete AV block would lead to a slower rhythm.
D: the ventricles would contract at the same rate as the atria - Incorrect, as the ventricles and atria have different intrinsic rates.
The intestinal flora is:
- A. Mainly viruses
- B. Mainly found in the duodenum
- C. Needed for normal digestion
- D. Mainly found in the colon
Correct Answer: D
Rationale: The correct answer is D: Mainly found in the colon. Intestinal flora, also known as gut microbiota, is primarily located in the colon. This is because the colon provides an ideal environment for the growth and survival of the diverse array of beneficial bacteria that make up the intestinal flora. These bacteria play a crucial role in various physiological functions, such as digestion, immune system regulation, and vitamin production. Choices A, B, and C are incorrect because intestinal flora are predominantly bacteria (not viruses), are not solely located in the duodenum but throughout the gastrointestinal tract, and are essential for normal digestion, not just needed.
Which statement accurately describes vitamin deficiencies?
- A. The two nutrients most often lacking in the diet of a vegan are vitamin B6 and folic acid.
- B. Vitamin imbalances occur frequently in the United States because of excessive fat intake.
- C. Surgery on the GI tract may contribute to vitamin deficiencies because of impaired absorption.
- D. Vitamin deficiencies in adults most commonly are clinically manifested by disorders of the skin.
Correct Answer: C
Rationale: The correct answer is C because surgery on the gastrointestinal (GI) tract can impair the absorption of essential vitamins leading to deficiencies. This is due to the fact that many vitamins are absorbed in the GI tract, and any alteration or removal of parts of the tract can hinder this process. For example, surgeries like gastric bypass can reduce the absorption of certain vitamins such as B12.
Choice A is incorrect because vegan diets can be deficient in various nutrients, not just vitamin B6 and folic acid.
Choice B is incorrect because vitamin imbalances are not solely due to excessive fat intake but can also be caused by various factors.
Choice D is incorrect because while skin disorders can be a symptom of vitamin deficiencies, they are not the most common clinical manifestation in adults.
A nurse is caring for a client who is receiving total parenteral nutrition (TPN). The nurse notices that the solution bag is almost empty and there is not another bag of TPN to administer. Which of the following IV solutions should the nurse administer until the next bag of TPN solution is available?
- A. 10% dextrose in water (D10W)
- B. 0.45% sodium chloride (0.45% NaCl)
- C. Lactated Ringer's solution
- D. 5% dextrose in lactated Ringer's solution (D5LR)
Correct Answer: A
Rationale: The correct answer is A: 10% dextrose in water (D10W). When a TPN bag is almost empty, abruptly stopping it can lead to hypoglycemia. Administering D10W provides a temporary source of glucose to prevent this. D10W is a hypertonic solution that delivers a high concentration of dextrose for energy. Option B (0.45% NaCl) is hypotonic and lacks the necessary glucose content. Option C (Lactated Ringer's solution) does not contain glucose, and option D (D5LR) contains lactate, which may not be suitable for all patients. Administering D10W is the most appropriate choice to prevent hypoglycemia until the next bag of TPN is available.