What are the 'formed elements' of blood?

Erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.

Describe the main function of erythrocytes.

Transport oxygen throughout the body.

Hemoglobin binds to oxygen and facilitates its transport throughout the body.

I can describe the components of blood, including plasma, and their functions.

1
Blood is considered a connective tissue and is comprised of formed elements, or blood cells, suspended in plasma.
2
Erythrocytes transport oxygen via hemoglobin, while leukocytes are part of the immune system and defend against pathogens.
3
Platelets, which are fragments of large cells, are essential for blood clotting and hemostasis, the process by which the body stops bleeding.