Question

I am a red coloured substances present in blood​

Answer 1

Answer:-

Human blood is red because of the protein hemoglobin, which contains a red-colored compound called heme that's crucial for carrying oxygen through your bloodstream. Heme contains an iron atom which binds to oxygen; it's this molecule that transports oxygen from your lungs to other parts of the body.

Answer 2

Answer:

haemoglobin is the answer