The mammalian heart has ___ chambers.
These cells play a vital role in defending the body against infection
_______ function in the life-saving process of clotting blood.
A fish's heart has ___ chambers.
True or false:
Blood traveling in veins is blue.
True or false:
Arteries always carry blood away from the heart.
True or false:
Arteries always carry oxygenated blood.
The blood in the vena cava is...
An open circulatory system is one that has:
What is the smallest type of cell in the blood called?