Bone marrow

Bone marrow is like the factory where our body makes new blood cells. It's like a special kind of jelly that is found inside of the bones, especially in the middle of the long bones like your arms and legs.

When you go to a doctor to get a shot or have your blood taken, they use a needle to go through your skin and get the blood from your veins. But if a doctor needs to take a look at your bone marrow or give you a special kind of medicine, they will use a bigger needle to go inside of your bone and get some of the jelly-like bone marrow.

Inside of the bone marrow, there are special cells called stem cells. These special cells are like the superheroes of our body because they can turn into many different kinds of cells that we need, like red blood cells, white blood cells, and platelets.

Red blood cells are really important because they carry oxygen around our body. White blood cells are like the soldiers that protect our body from bad germs that can make us sick. And platelets are important because they help our blood to clot and stop bleeding if we get a cut.

So even though we can't see it, bone marrow is a really important part of our body that helps us stay healthy!