The insulin receptor is a:

Correct Answer: B

Rationale: The correct answer is B: Tyrosine protein kinase receptor. The insulin receptor is a type of receptor that belongs to the tyrosine kinase family. It works by phosphorylating tyrosine residues on itself and other proteins, triggering a signaling cascade that regulates glucose uptake and metabolism. This process is crucial for maintaining blood glucose levels. Option A is incorrect because the insulin receptor is not an ion channel regulating receptor. Option C is incorrect as the insulin receptor does not belong to the G-protein coupled receptor family. Option D is incorrect as the insulin receptor is indeed a tyrosine protein kinase receptor.

Correct Answer: D

Rationale: The correct answer is D: Sodium bicarbonate. In diabetic ketoacidosis, the blood becomes acidic due to ketone accumulation. Administering sodium bicarbonate can worsen the acidosis by shifting the pH too rapidly. Insulin is essential to lower blood glucose levels, IV fluids are necessary to correct dehydration, and potassium chloride is needed to replenish electrolytes. Sodium bicarbonate is not recommended as it can lead to potential complications.

Correct Answer: A

Rationale: The correct answer is A. Sulfonylureas work by increasing insulin release from the pancreas, which helps lower blood sugar levels. Nondiabetics already have a properly functioning insulin system, so sulfonylureas would not have a significant impact on their blood sugar levels. In contrast, type 1 and type 2 diabetics have insulin deficiency or resistance, making them more responsive to sulfonylureas. Obese diabetics may also benefit from sulfonylureas as they can help improve insulin sensitivity. In summary, sulfonylureas are effective in individuals with diabetes but not in nondiabetics.

Correct Answer: D

Rationale: Rationale: Rosiglitazone is the correct answer as it is not a sulfonylurea but acts by a similar mechanism to enhance insulin sensitivity in peripheral tissues, unlike sulfonylureas that directly stimulate insulin release from pancreatic beta cells. Glimepiride, Repaglinide, and Miglitol are sulfonylureas or alpha-glucosidase inhibitors, which directly stimulate insulin release or delay carbohydrate absorption, respectively, making them unsuitable choices for the question.

Correct Answer: A

Rationale: The correct answer is A: Acarbose. Acarbose inhibits intestinal brush border α-glucosidase enzymes, leading to delayed carbohydrate digestion and absorption. This mechanism helps in controlling postprandial blood glucose levels. Pioglitazone (B) improves insulin sensitivity, Metformin (C) reduces hepatic glucose production, and Guargum (D) is a dietary fiber with no direct impact on α-glucosidase enzymes.