What Does An Atom REALLY Look Like? - Duration: 8:44. The Science Asylum 600,649 views
A NEGATIVE result from a Hemoccult II test means that there was no evidence of occult (hidden) blood detected in your stool specimen. However, this test is not a complete cancer detection examination; it only detects blood in the stool.
A positive blood group means that the person has Rh antigen on the red blood cells whereas a negative blood group means that the Rh antigen is absent on the red blood cells. Unlike ABO system, an Rh-ve person will not have anti-Rh antibody in the blood unless he/she has been previously exposed to Rh +ve blood. person with O-negative blood group is a universal donor as O-negative blood can be transfused to any blood group. Blood group is determined by the presence of antigen(s) on the membrane of red blood cells. The antigens are special molecules that can elicit an immune response.