| Red blood cells(RBCs) | White blood cells(WBCs) |
| (i) These are minute biconcave disc like structures, flat in centre, thick and round at the periphery and nuclei are absent in mature RBCs. | These are amoeboid and can produce pseudopodia and have a nucleus. |
| (ii) These contain a respiratory pigment haemoglobin. | Haemoglobin is not present. |
| (iii) RBCs help in transport of oxygen and CO2. | WBCs help in protection of the body against infections from the germs. |
| (iv) The number of RBCs in adult male is 5 million per cubic millimetre. | Their number is usually about 4000-8000 per cubic millimetre. |
| (vi) Their average life span is about 120 days. | Their average life span is about two weeks. |
