Imp. Topic in physiology
Asking for Preferences
Here's a high-yield overview of important physiology topics for MBBS/NEET/USMLE across all systems:
🫀 Cardiovascular Physiology
| Topic | Key Concepts |
|---|---|
| Cardiac cycle | Systole/diastole, heart sounds (S1–S4), JVP waveforms |
| Action potential | Fast (ventricle) vs. slow (SA/AV node) AP; phases 0–4 |
| Frank-Starling law | Preload, afterload, contractility |
| ECG interpretation | P, QRS, T waves; PR/QT intervals |
| Cardiac output | CO = HR × SV; Fick's principle |
| Pressure-volume loop | Changes in preload/afterload/contractility |
| Baroreceptor reflex | Carotid sinus, aortic arch; control of BP |
| Special circulations | Coronary, pulmonary, cerebral, fetal |
🫁 Respiratory Physiology
| Topic | Key Concepts |
|---|---|
| Lung volumes & capacities | TV, IRV, ERV, RV, FRC, TLC, VC — values & clinical relevance |
| V/Q ratio | Normal = 0.8; apex (high) vs. base (low) |
| Oxygen-Hb dissociation curve | P50, Bohr/Haldane effects; shifts L/R |
| CO₂ transport | Dissolved, HbCO₂, bicarbonate (70%) |
| Compliance & airway resistance | Surfactant role; elastic recoil |
| Hypoxic pulmonary vasoconstriction | HPV mechanism |
| Control of respiration | Central/peripheral chemoreceptors; CO₂ vs. O₂ drive |
| Spirometry patterns | Obstructive vs. restrictive — FEV1/FVC |
🩸 Blood & Immunity
| Topic | Key Concepts |
|---|---|
| Hemoglobin | Types (HbA, HbA2, HbF, HbS), structure |
| Erythropoiesis | Stages, EPO, iron metabolism |
| Hemostasis | Primary (platelet plug) → Secondary (coagulation cascade) |
| Blood groups | ABO genetics, Rh factor, transfusion reactions |
| WBC functions | Neutrophil killing, lymphocyte types (CD4/CD8) |
| Complement system | Classical, lectin, alternative pathways |
🧠 Neurophysiology
| Topic | Key Concepts |
|---|---|
| Resting membrane potential | -70 mV; Nernst equation, Goldman equation |
| Nerve action potential | All-or-nothing law, absolute/relative refractory period |
| Synaptic transmission | EPSPs, IPSPs; neurotransmitters |
| Reflexes | Stretch reflex (monosynaptic), withdrawal reflex |
| Special senses | Vision (phototransduction), hearing (cochlea, tonotopy) |
| Sleep | REM vs. NREM; neurotransmitters involved |
| CSF | Formation (choroid plexus), circulation, composition |
| EEG waves | Alpha, beta, theta, delta — states |
🧪 Renal & Acid-Base
| Topic | Key Concepts |
|---|---|
| GFR & clearance | Inulin clearance = true GFR; PAH = RPF; creatinine |
| Tubular transport | PCT (glucose, amino acids, bicarbonate reabsorption) |
| Countercurrent mechanism | Loop of Henle, vasa recta |
| ADH & aldosterone | Osmoregulation vs. volume regulation |
| Acid-base disorders | Metabolic/respiratory acidosis & alkalosis; anion gap |
| Henderson-Hasselbalch | pH = pKa + log([HCO₃⁻]/[CO₂]) |
| RAS axis | Renin → Ang I → Ang II → Aldosterone |
| Micturition | Detrusor, internal/external sphincter, spinal control |
🔬 Endocrine Physiology
| Topic | Key Concepts |
|---|---|
| Hypothalamo-pituitary axis | Releasing/inhibiting hormones; portal circulation |
| Thyroid hormones | T3/T4 synthesis, iodine steps, feedback loop |
| Insulin & glucagon | Glucose homeostasis; GLUT transporters |
| Adrenal cortex | Aldosterone, cortisol, DHEA — zones |
| Calcium regulation | PTH, Calcitonin, Vitamin D — mechanisms |
| Growth hormone | IGF-1 axis; somatostatin inhibition |
| Reproductive hormones | Menstrual cycle; LH surge; testosterone |
🍽️ GI Physiology
| Topic | Key Concepts |
|---|---|
| GI motility | MMC (interdigestive), peristalsis, segmentation |
| Gastric secretion | HCl (parietal cells), pepsinogen (chief cells), phases |
| Pancreatic secretion | Trypsinogen activation; bicarbonate role |
| Bile | Enterohepatic circulation; bile salts & lipid digestion |
| Absorption | Iron (duodenum), B12 (ileum), fat (lacteals) |
| GI hormones | Gastrin, CCK, Secretin, GIP, Motilin |
🔑 High-Yield Extras (Exams Love These)
- Nernst vs. Goldman equation — always asked
- Fick's principle — O₂ consumption & cardiac output
- Starling forces — edema mechanisms
- Gibbs-Donnan equilibrium
- Dead space — anatomical vs. physiological
- Oxygen cascade (PO₂ at each step: atmosphere → mitochondria)
- Willenbrand factor — links platelet plug to coagulation
- Crossed extensor reflex
📚 Recommended Resources
- Guyton & Hall — gold standard for mechanisms
- Ganong's Review — concise with clinical correlates
- BRS Physiology (Linda Costanzo) — best for USMLE/NEET MCQs
- Najeeb Lectures — for visual/conceptual understanding
Want me to dive deep into any specific topic — with diagrams, mnemonics, or MCQ-style breakdowns?
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