Composition of blood

• Blood is a tissue and a fluid, that transports oxygen and nutrients around the body.

• Blood contains a fluid called plasma.

• Blood helps us to protect against disease.

• Blood is pumped through blood vessels by our heart.

• Plasma is the straw-coloured liquid, that makes up about 55% of the blood volume.

• Red blood cells transport oxygen to the organ.

• Red blood cells have no nucleus.

• Red blood cells contain haemoglobin.

• White blood cells are part of the body's immune system.

• There are several types of white cells, called neutrophils (polymorphs), lymphocytes, eosinophils, monocytes and basophils.

• White blood cells have a nucleus.

• Platelets are tiny fragments of cells. they help in clotting of blood.