PATHOLOGY

Detailed explanation-1: -It’s bright red when the arteries carry it in its oxygen-rich state throughout the body. And it’s still red, but darker now, when it rushes home to the heart through the veins.

Detailed explanation-2: -It is the iron in hemoglobin specifically that gives blood its red colour. The actual colour ranges from crimson to a dark brown-blood depending on how oxygenated the blood is, and may have a slightly orange hue.

Detailed explanation-3: -Blood is always red, but the shade of red depends on how much oxygen is in the red blood cells. When you breathe in, you are filling your blood cell with oxygen, and it gives them a very bright red color. As blood travels through your body, it loses the oxygen and takes on carbon dioxide (which you exhale).