So we have one two three carbons, and we also have these two phosphate groups. And as we'll see in just a moment, these two phosphate groups, because they have a negative charge, they play a crucial role in actually binding to our deoxyhemoglobin molecules. So once our two three BPG molecules into the matrix, they're then diffused via the capillary wall and into the blood plasma found inside the capillary. So this is our capillary, and inside the capillary, we have red blood cells. Our erythrocytes death carry our hemoglobin proteins. So within our red blood cell, we have many of these hemoglobin proteins as shown.