Yet the blood vessels, they extend from the surface of the brain down to reach every single cell in the brain, which means that fluid that's traveling along the outsides of these vessels can gain easy access to the entire brain's volume, so it's actually this really clever way to repurpose one set of vessels, the blood vessels, to take over and replace the function of a second set of vessels, the lymphatic vessels, to make it so you don't need them.
No krvne žile se ipak šire od površine mozga i dopiru do svake stanice u mozgu, što znači da tekućina koja putuje uz rub žila ima lak pristup cijelom mozgu, pa je to vrlo pametan način prenamjene jednog sustava žila, krvnih žila, kako bi preuzeo i zamijenio funkciju drugog sustava žila, limfnih žila, kako ih ne bismo uopće trebali.