Common Errors, Traps, and Misconceptions in NEET

WRONG: "AVN is the pacemaker" → CORRECT: SAN is the primary pacemaker (70-75 bpm); AVN is a delay relay (secondary pacemaker, 40-60 bpm, only if SAN fails)
WRONG: "QRS = ventricular contraction" → CORRECT: QRS = ventricular DEPOLARIZATION (electrical). Mechanical contraction follows depolarization
WRONG: "Pulmonary arteries carry oxygenated blood" → CORRECT: Pulmonary arteries carry DEOXYGENATED blood (right ventricle → lungs). The universal exception
WRONG: "RBCs formed in spleen" → CORRECT: RBCs FORMED in red bone marrow. Spleen is the DESTRUCTION site (graveyard)
WRONG: "AB is the universal donor" → CORRECT: O is the universal DONOR; AB is the universal RECIPIENT
WRONG: "Atrial repolarization is visible as a wave after P wave" → CORRECT: Atrial repolarization is MASKED by the QRS complex
WRONG: "Erythroblastosis fetalis occurs in first pregnancy" → CORRECT: First pregnancy sensitizes the mother; disease occurs in SECOND or later pregnancies
WRONG: "Basophils perform phagocytosis" → CORRECT: Neutrophils and macrophages phagocytose; basophils SECRETE histamine and heparin
WRONG: "Serum = plasma" → CORRECT: Serum = plasma minus fibrinogen and clotting factors
WRONG: "Bicuspid valve is on the right side" → CORRECT: Bicuspid (mitral) = LEFT AV valve; tricuspid = RIGHT AV valve
WRONG: "Joint diastole is the shortest cardiac phase" → CORRECT: Joint diastole (0.4 s) is the LONGEST phase; atrial systole (0.1 s) is the shortest
WRONG: "T-lymphocytes produce antibodies" → CORRECT: B-lymphocytes produce antibodies; T-lymphocytes perform cell-mediated immunity