In anatomy and physiology, what is hemoglobin and how does it carry oxygen?
a) Hemoglobin is a type of white blood cell that carries oxygen by binding it to iron molecules.
b) Hemoglobin is a protein found in red blood cells that carries oxygen by binding it to heme groups.
c) Hemoglobin is a hormone that regulates oxygen levels in the blood by inhibiting its release from red blood cells.
d) Hemoglobin is a neurotransmitter that facilitates the transport of oxygen across synaptic clefts.