Answer: Antigens
Explanation: The ABO system of blood grouping is based on the basis of the type of antigens that are present in the red blood cells. Erythrocytes is another name for the red blood cells. Antigens are molecules that are capable of eliciting immune response. There are two types of antigens: antigen A and B. Blood type A has only antigen A, blood type B has only antigen B, blood type AB has both antigen A and B while blood type O has no antigen (neither A nor B antigen).
Similarly, Rh trait is determined by the presence or absence of rhesus antigen in the erythrocytes. Rhesus antigen is an antigen first discovered in rhesus monkey. Rh+ indicates the presence of rhesus antigen in the red blood cells while Rh- indicates the absence of rhesus antigen in the red blood cells.
A. 1000 grams. 1000 is divided by ten each time it goes up the trophic scale. since it goes up 2, 3 and 4, the answer is 1000. (1000/10/10/10=1)
Answer:
Ion
Explanation:
An Ion is exactly as stated it bears either a positive or negative charge.