Blood Video

What percentage of your body weight does blood account for?

• About 12%

• About 5%

• About 15%

• About 8%

During a blood donation, what is the typical volume of blood taken from a donor?

• About two pints

• Half a pint

• About a pint

• Three pints

What triggers the initial constriction of a blood vessel following an injury?

• The decrease in blood pressure

• The rupture of the blood vessel

• The activation of platelets

• The exposure of collagen fibers

What is the role of fibrin in the blood clotting process?

• It forms a mesh that traps blood cells and platelets

• It fights infection

• It dilutes the blood to prevent clotting

• It transports oxygen

Which blood type is known as the universal donor?

• Type AB

• Type O

• Type A

• Type B