What is hemoylobin?

Answer 1

I think you mean "hemoglobin"? It is the molecule in blood which transports the oxygen to the rest of the body. In other words, its like a car that gets the oxygen from home (the air you breathe) to work (nourishing your cells in your body) so it can do its job and keep us alive. Each hemoglobin molecule can only carry four oxygen molecules, so when your hemoglobin count is low, you are carrying less oxygen around to your body.