Here's why:

* Plasma: This is the liquid component of blood, making up about 55% of its volume. It's primarily water, but also contains proteins, electrolytes, nutrients, and waste products.

* Cells: Blood contains several types of cells, including:

* Red blood cells (erythrocytes): Carry oxygen throughout the body.

* White blood cells (leukocytes): Fight infections and protect the body from disease.

* Platelets (thrombocytes): Help with blood clotting.

Let me know if you'd like to know more about blood!