Vampire 
                Name at least 2 differences between red and white blood cells.
Red blood cells transport oxygen, white blood cells protect the body from disease and infection.
Red Blood Cells (Erythrocytes) and White Blood Cells (Leukocytes)
Red=more White=Less
Red blood cells are smaller, White blood cells are larger
Red= 1 type White=multiple types
What is a mosquitoes favorite blood type?
Type O
How many tests get run on every unit of donated blood?
Bonus: How many units of blood gets used a day?
15 tests (11 are for diseases).
around 29,000
How many red blood cells does the human body make a second?
About 2 million red blood cells a second
How many blood types can cows have?
800+