What is the name of a surface membrane molecule that causes an immune reaction? 2. What is the average range of hematocrit for a normal female? 3. What is the average range of hematocrit for a normal male? 4. What percent of the blood volume consists of formed elements? 5. A person with blood type B has what kind of agglutinins (antibodies)? 6. A person has antibody A and antibody B in his or her blood, with no Rh antibody. What blood type does this person have? 7. A total of 240 erythrocytes are counted in the hemacytometer chamber. What is the red blood cell count of th individual in terms of erythrocytes per cubic milliliter?