The correct answer is b, antigens
They put a camera up to the microscope! I’ve done that with my phone camera and it’s so cool!
no because Separation of oxygenated and deoxygenated blood in the heart of three types of animals. The three-chambered frog heart mixes oxygenated and deoxygenated blood in the ventricle. Therefore, the body never receives fully oxygen-rich blood.
