types of blood vessels:
1. Arteries
⇒thick walled blood vessels
⇒carry oxygenated blood away from the heart to the cells, tissues and organs of the body.
⇒Aorta is the largest artery.
2. Capillaries
⇒ the smallest blood vessels in the body found in all organs where exchange of substance occur.
⇒the actual site where gases and nutrients exchanged.
3. Veins
⇒ thin walled blood vessels that carry deoxgenated blood to the heart.
⇒largest veins is the superior and inferior vena cava.
