In the Gram Stain procedure, which component acts as the mordant?

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: 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.

Correct Answer: C

Rationale: The Sinoatrial (SA) Node, often called the heart's natural pacemaker, is situated within the upper wall of the Right Atrium. It initiates the electrical impulses that regulate the heartbeat. Choices A, B, and D are incorrect because the SA node is not located in the Mitral Valve, Right Ventricle, or Left Atrium. It is specifically positioned in the Right Atrium to coordinate the heart's rhythm and timing.

Correct Answer: C

Rationale: The correct answer is 'absorption.' The three main functions of the digestive system are digestion, absorption, and elimination. Absorption refers to the process of absorbing nutrients and other substances from the digested food into the bloodstream. Choices A, B, and D are incorrect: Constriction is not a primary function of the digestive system, relaxation is not a distinct function in this context, and peristalsis is a muscular movement that aids in digestion but is not one of the three main functions of the digestive system.

Correct Answer: C

Rationale: When examining a 6-year-old child, it is important to consider their sense of modesty. The child should undress themselves, leaving underpants on and using a gown or drape to maintain privacy. Additionally, a school-age child like a 6-year-old is curious about how equipment works, so it is beneficial to explain the purpose and function of the tools being used. The examination sequence should typically progress from the child's head to the toes to ensure a thorough assessment. Therefore, choices A, B, and D are incorrect as they do not align with the appropriate approach to examining a 6-year-old child.