Summary
Highlights
Blood is essential for life, carrying nutrients and oxygen to cells, removing waste, fighting infections, and transporting hormones.
Plasma is the yellowish liquid portion, making up 55% of blood. It contains water, salts, antibodies, enzymes, and proteins.
Also called erythrocytes, RBCs comprise 45% of blood. They contain hemoglobin, which carries oxygen, giving blood its red color. RBCs live for 120 days and are produced in the bone marrow.
Known as leukocytes, WBCs are part of the immune system, protecting the body against invaders and infectious diseases. They are derived from hematopoietic stem cells in the bone marrow.
Platelets rush to damaged blood vessels, forming clots to repair them and prevent further damage.
Oxygen from the lungs enters the blood and travels through pulmonary veins to the heart's left side, then is pumped through the aorta to the rest of the body.
There are eight blood types: A negative, A positive, B negative, B positive, O negative, O positive, AB negative, and AB positive.
To keep blood healthy and clean, one should eat dried fruits, green vegetables, beans, whole grains, and low-fat dairy.
Blood is composed of plasma, red blood cells, white blood cells, and platelets. Each component plays a vital role.