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To determine blood groups, there is a method of extracting a chemical from human blood which, when mixed with a sample of the blood in question will react in a particular way according to the blood group. However, to get enough of the solution a great deal of human blood is required. But fortunately, snails’ eggs, which are the size of a pinhead, contain the same chemical – in fact, the blood of five donors would be required to supply the same amount of the chemical as is found one of the snail’s eggs.
Blood Groups
Human Blood
Donors
Snails Save Lives