NEET & AIPMT PYQ – Body Fluids and Circulation

This section contains high-frequency NEET/AIPMT previous year questions strictly derived from NCERT. Repeatedly tested areas include blood groups, clotting, cardiac cycle, ECG, heart sounds, and circulatory disorders.

🔑 Important NEET Exam Tips

  • Blood group O = universal donor, AB = universal recipient (RBC-based)
  • Fibrinogen → fibrin conversion is enzyme-driven
  • Left ventricle has thickest wall
  • ECG represents electrical, not mechanical activity
  • Lub–Dub sounds correspond to valve closure
  • Hypertension = >140/90 mm Hg
  • CO = HR × SV

NEET Revision Kit: Rapid Recall

1. The "Heart Math" Cheat Sheet

  • Cardiac Output (CO) = Stroke Volume(SV)×Heart Rate(HR)Stroke\ Volume (SV) \times Heart\ Rate (HR)
  • Standard Values: SV≈70 mLSV \approx 70\ mL, HR≈72 bpmHR \approx 72\ bpm, CO≈5000 mL/minCO \approx 5000\ mL/min.
  • Duration: Cardiac Cycle = 0.80.8 sec (Atrial Systole 0.1s + Ventricular Systole 0.3s + Joint Diastole 0.4s).

2. ECG Wave Decoder

  • P-Wave: Atrial Depolarisation (Contraction).
  • QRS Complex: Ventricular Depolarisation (Contraction initiates).
  • T-Wave: Ventricular Repolarisation (Relaxation).
  • Count Heart Rate: Count QRS complexes.

3. Blood & Clotting Essentials

  • Universal Donor: O- (Technically O negative).
  • Universal Recipient: AB+ (Technically AB positive).
  • Clotting Factor IV: Calcium (Ca++Ca^{++}).
  • Enzyme Cascade: Prothrombin →Thrombokinase\xrightarrow{Thrombokinase} Thrombin →\rightarrow Fibrinogen →\rightarrow Fibrin.

4. Disorder Keywords

  • Hypertension: >140/90>140/90 mmHg.
  • CAD (Atherosclerosis): Lumen narrowing, plaque (cholesterol/Ca).
  • Angina: Chest pain, insufficient O2O_2.
  • Heart Failure: Ineffective pumping (Congestion).
  • Cardiac Arrest: Heart stops beating.