With respect to its effect on colon microflora, fiber is considered a:

Correct Answer: A

Rationale: The correct answer is A: prebiotic. Fiber acts as a prebiotic by providing a food source for beneficial bacteria in the colon, promoting their growth and activity. This helps maintain a healthy balance of microflora in the gut. Choice B, probiotic, is incorrect as fiber itself does not contain live beneficial bacteria but rather supports their growth. Choice C, functional food, is too broad and doesn't specifically address fiber's role in promoting beneficial bacteria. Choice D, protective agent, is vague and does not directly relate to fiber's specific function in colon microflora.

Correct Answer: A

Rationale: Patients with periodontal disease may require increased protein intake due to the physiological response to inflammation and infection, which can negatively impact protein synthesis. Protein is essential for wound healing and tissue repair, and an infection can increase the body's protein requirements. Therefore, ensuring an adequate protein intake is particularly important for these patients. Choice A is correct because the statement and reason are both accurate and directly related to each other, supporting the increased protein needs in patients with periodontal disease. Choices B, C, and D are incorrect as they do not accurately assess the relationship between the statement and the reason provided in the question.

Correct Answer: B

Rationale: The correct answer is B: Breast. Lactose is synthesized in the breast during lactation to produce breastmilk. The liver is responsible for various metabolic functions but does not synthesize lactose. The kidney's primary role is in filtering blood and regulating electrolytes, not lactose synthesis. The pancreas is involved in producing digestive enzymes and insulin, not lactose synthesis.

Correct Answer: B

Rationale: The correct answer is B: Supply energy. The primary function of macronutrients such as carbohydrates, fats, and proteins is to supply energy for various bodily functions. Choices A, C, and D are incorrect because while regulating metabolic processes, maintaining homeostasis, and controlling cellular activity are essential functions in the body, they are not the primary roles of macronutrients. Macronutrients mainly serve as a source of energy to support daily activities and bodily functions.

Correct Answer: D

Rationale: The Dietary Reference Intake (DRI) for protein is primarily determined by an individual's body weight. This is because the body's protein requirement is proportionate to its size, which is generally reflected in the body weight. Therefore, choice D is correct. Choices A, B, and C are incorrect: While factors such as fatty acid intake, gender, and height can influence an individual's overall nutritional needs, they do not directly determine the DRI for protein.

Correct Answer: A

Rationale: Short-chain fatty acids are the preferred fuel for the cells lining the colon. They provide energy and support gut health by serving as a fuel source for these cells. Long-chain fatty acids are not the preferred fuel for colon cells as they are harder to digest and absorb in this part of the digestive system. Amino acids are the building blocks of proteins and not the primary energy source for colon cells. Glucose is the main energy source for most cells in the body, but colon cells prefer short-chain fatty acids.

Correct Answer: D

Rationale: In a patient with liver cirrhosis, weight gain due to fluid retention can mask Protein-Energy Malnutrition (PEM) symptoms. This can lead to an increase in weight, making it challenging to identify weight loss or muscle wasting associated with PEM. Therefore, option D is correct. Options A, B, and C are incorrect because fluid retention and weight gain related to liver cirrhosis do not necessarily hide the symptoms of liver failure, gallbladder disease, or heart failure.

Correct Answer: D

Rationale: The correct answer is 'D'. Fast food is generally not deficient in protein since it often contains meat, a significant source of protein. On the other hand, fast food is known to lack essential nutrients like Vitamin A and certain minerals, as mentioned in choices 'A' and 'C'. Choice 'B' is also accurate as many fast food establishments have started offering healthier options such as salads due to customer demands. Therefore, all options are true except 'D', which makes it the exception.

Correct Answer: A

Rationale: During the process of deamination, the nitrogen portion of amino acids is converted to ammonia. This occurs in the liver as part of the process to remove excess nitrogen from the body. Choice B, 'protein,' is incorrect as deamination breaks down amino acids rather than synthesizing proteins. Choice C, 'purines,' is incorrect as purines are a type of nitrogenous base found in DNA and RNA, not a product of deamination. Choice D, 'glycogen,' is incorrect as glycogen is a storage form of glucose and not a product of amino acid deamination.