Circulatory System
Biology · परिसंचरण तंत्र
📋Quick Overview
The circulatory system transports blood, nutrients, oxygen, and waste. Heart is a muscular organ with 4 chambers: 2 Atria (upper) + 2 Ventricles (lower). William Harvey discovered blood circulation (1628). Blood groups: A, B, AB (universal recipient), O (universal donor). Rh factor: Rh+ or Rh-. Blood has RBC (carry O₂), WBC (fight infection), Platelets (clotting), Plasma (liquid).
📖Blood Components
| Component | Also Called | Function | Key Facts |
|---|---|---|---|
| RBC (Red Blood Cells) | Erythrocytes | Carry oxygen (haemoglobin) | No nucleus in mammals, made in bone marrow, life=120 days |
| WBC (White Blood Cells) | Leucocytes | Fight infections (immunity) | Larger than RBC, have nucleus, fewer in number |
| Platelets | Thrombocytes | Blood clotting | No nucleus, smallest, made in bone marrow |
| Plasma | — | Liquid part (55%) carries nutrients, waste, hormones | 90% water, contains fibrinogen (clotting) |
📖Blood Groups
| Blood Group | Antigen (on RBC) | Antibody (in Plasma) | Can Donate To | Can Receive From |
|---|---|---|---|---|
| A | A | Anti-B | A, AB | A, O |
| B | B | Anti-A | B, AB | B, O |
| AB | A and B | None | AB only | A, B, AB, O (Universal Recipient) |
| O | None | Anti-A and Anti-B | A, B, AB, O (Universal Donor) | O only |