Which of the following tests would MOST LIKELY be performed on a patient who is being monitored for coagulation therapy?

Correct Answer: A

Rationale: The correct answer is A: PT/INR. Prothrombin times (PT/INR) are commonly used to monitor patients on Coumadin (warfarin) therapy, an anticoagulant that slows the blood's ability to clot. Monitoring PT/INR levels helps ensure the patient is receiving the appropriate dosage of Coumadin. Choice B, CBC (Complete Blood Count), is a general test that provides information on red blood cells, white blood cells, and platelets but is not specific to monitoring coagulation therapy. Choice C, PTT (Partial Thromboplastin Time), is another coagulation test but is not as commonly used for monitoring Coumadin therapy. Choice D, WBC (White Blood Cell count), is unrelated to monitoring coagulation therapy and is used to assess immune system function.

Correct Answer: C

Rationale: A patient with blood type AB has AB antigens on their red blood cells. This means they can only receive blood products that are compatible with these antigens. Choice A is incorrect because an AB patient cannot receive plasma from a type B donor due to the antibodies present in type B plasma. Choice B is incorrect because an AB patient cannot receive whole blood from a type A donor as it contains incompatible antigens. Choice C is the correct answer because an AB patient can receive packed RBCs from a type O donor. Type O donors have no A or B antigens, making their blood compatible for transfusion to recipients with any blood type. Therefore, choices A and B are incorrect, and the correct choice is C.

Correct Answer: C

Rationale: In the Gram Stain procedure, the mordant is Gram's Iodine. The purpose of the mordant is to form a complex with the crystal violet, enhancing its ability to bind to the cell wall. Crystal violet is actually the primary stain used in the Gram Stain procedure to initially color all cells. Methyl alcohol is the decolorizer that removes the crystal violet from certain cell types. Safranin is the counterstain used to stain those cells that did not retain the crystal violet stain after the decolorization step.

Correct Answer: A

Rationale: To properly read a meniscus, it is essential to hold the measuring device at eye level to avoid parallax error. Reading the bottom of the curve of the liquid level is correct because the meniscus is the concave or convex curve at the liquid's surface. Choice B is incorrect because reading the top of the curve where the liquid adheres to the walls of the container can lead to inaccurate measurements. Choices C and D are incorrect as they suggest holding the device at table level, which can introduce parallax error and result in an incorrect reading.

Correct Answer: A

Rationale: A urine pregnancy test detects HCG in a pregnant woman's urine. Blood levels of HCG are usually higher and register earlier than HCG levels in the urine. Choice A is correct because urine pregnancy tests may be negative even if a blood pregnancy test is positive due to the differences in HCG levels in blood and urine. Choice B is incorrect because a urine pregnancy test can be positive throughout pregnancy, not just in the first trimester. Choice C is incorrect because LH (luteinizing hormone) is not the hormone detected in a pregnancy test; it is HCG (human chorionic gonadotropin). Choice D is incorrect because not all the statements provided are true.