Blood

Plasma- About 55% of our blood. It is the liquid part of blood. It is mostly water.

Red blood cells- They are red because of the hemoglobin.

White blood cells- larger than red blood cells, and they have a nucleus. WBC help to defend against bacteria and viruses that get into the body.

Platelets - little fragments of cells. If a blood vessel gets damaged, the platelets help the blood to clot and seal the wound.

Describe which two ways in which white blood blood cells look different from red blood cells.