the.com/bone marrow
The body's blood factory, hiding inside the bones that hold you up.
means The soft, spongy tissue inside bones where red blood cells, white blood cells, and platelets are manufactured.
from Straightforward Old English heritage: 'bone' traces back to bān, and 'marrow' comes from mearg, both common Germanic words with cousins across the old Germanic languages (like German Mark). No hidden drama here — the term simply did what plain Old English does best, naming the greasy, vital stuff packed inside bones exactly as it appears when you crack one open.
- daily output
- makes about 500 billion blood cells a day
- two types
- red marrow makes blood, yellow marrow stores fat
- aging shift
- red marrow turns yellow as you grow older
- transplant trick
- donor marrow can regrow an entire immune system