A female patient needs a whole blood transfusion. In order for transfusion services (the blood bank) to prepare the correct product a sample of the patient's blood must be obtained for:

Correct Answer: B

Rationale: A blood type and crossmatch are essential before a whole blood transfusion to ensure compatibility between the donor and recipient. This process involves determining the patient's blood type (ABO and Rh) and testing for antibodies that could cause a transfusion reaction. A complete blood count and differential are not required for transfusion preparation. Blood culture and sensitivity are used to diagnose infections, not for transfusion compatibility. Therefore, blood type and crossmatch are the correct steps.

Correct Answer: C

Rationale: The liver, via portal vein metabolism, drives the first-pass effect, reducing oral drug bioavailability (e.g., morphine) before systemic circulation. Bladder and kidneys excrete, not metabolize first. Stomach degrades some, but liver's enzyme activity dominates. First-pass is liver-centric, shaping dosing.

Correct Answer: D

Rationale: Serotonin reuptake blockade increases synaptic levels. Buspirone, a 5-HT1A agonist, treats anxiety without reuptake effects. Pizotifen, a serotonin antagonist, prevents migraines. Granisetron, a 5-HT3 antagonist, controls nausea. Paroxetine, an SSRI, potently inhibits serotonin reuptake, elevating mood in depression. Sumatriptan activates 5-HT1 receptors. Paroxetine's mechanism is central to its antidepressant efficacy, distinguishing it from receptor modulators.

Correct Answer: D

Rationale: Second-generation antihistamines reduce sedation , a key benefit over first-generation. Alcohol , dry mouth , and urination aren't primary differences. D shows understanding, making it the best statement.

Correct Answer: B

Rationale: Levodopa is absorbed via an active transport mechanism using amino acid transporters, allowing it to cross the blood-brain barrier for its therapeutic effect.