<prompt> Acid Citrate DextroseACD, used to store blood, preserves the RBC for a period of 21 days. The storage period when adding phopshate alone and when adding adenine and phosphate together to ACD would respectively be?35 days and 42 days21 days and 35 days28 days and 45 days35 days and 28 days  <response>: The storage period when adding phosphate alone to ACD would be 21 days and when adding adenine and phosphate together would be 35 days. When adding phosphate to ACD, citrate Phosphate Dextrose CPD is formed- It has a storage period of 21 days. There is no change in the shelf life as phosphate only increases the 2,3 DPG levels of the stored blood. When adding both phosphate and adenine to ACD, Citrate phosphate Dextrose AdenineCPDA-1 is formed. It has a storage period of 35 days. It increases the shelf life by improving ATP synthesis of RBCs. Using additive solutions containing saline, addenine and glucose, with or without mannitol SAGM decreases RBC hemolysis, thus increasing the storage period to 42 days. Ref: WIntrobe,s Clinical Hematology 13th edition PGno: 550 