What is blood actually made of?
More than half of your blood is a pale yellow liquid, and the red cells are the minority.
▶ Start the storyBlood is a liquid called with three kinds of cells floating in it. Plasma, a pale straw-yellow fluid that is mostly water, makes up a bit more than half of your blood. The rest is red blood cells, white blood cells and , each with its own job: carrying oxygen, defending against germs, and sealing leaks.
Red blood cells are by far the most numerous. They are disk-shaped, they have no nucleus, and they use to carry oxygen around the body. They are also soft and deformable, so they can squeeze through the narrowest . White blood cells are part of the immune system and defend against infection, but they make up only about 1 percent of the blood. are not even whole cells, just small fragments, and they help form clots when a vessel is cut.
Red and white cells
- Red cells carry oxygen with
- White cells defend against infection
Platelets
- Tiny fragments of larger cells
- Release fibers that form clots
The is the delivery truck. It is mostly water, with proteins, glucose, mineral ions and hormones dissolved in it. It carries nutrients such as glucose to the tissues and carries away waste such as carbon dioxide and urea.
Your blood is also a factory output. Adults make about 2.4 million red blood cells every second in the red , because each one lives only 100 to 120 days before the removes it. An average adult has roughly 5 litres of blood, about 7 percent of body weight, and can lose almost 20 percent of it, about a litre, before even the first symptom, restlessness, begins.
Quiz me
0/3
Recap
Blood is about 55 percent plasma and about 45 percent cells, mostly red ones, with white cells and platelets as small minorities.
💡 A trick to remember it · Red cells are the couriers, white cells the guards, platelets the repair crew, and plasma is the river carrying them all.
Surprising fact · Adults make about 2.4 million red blood cells every second.
Sources (2)
No source, no claim. Every fact in this lesson (19 claims) cites at least one of these.