Is hematuria caused by the blood?

Yes. Hematuria means blood in the urine, it could be microscopic not visible by naked eyes or macroscopic visible, nephrologist and urologist could investigate the causes.
No. Hematuria (blood in the urine) comes from an abnormality somewhere between the interface of the blood in the kidneys (the glomerulus) down to the bladder. It can originate from the kidney, ureter or bladder and workup looks at all the anatomic structures.
Usually no. Causes of hematuria, blood in urine, include bleed in the urinary tract from a tumor, stone, or other reasons of injury or inflammation. However, causes from diseases of the kidney filtering units, glomerular disease, are not to be ignored. Blood disease e.g. Unusual thinnes of blood, called coagulopathy, may precipitate hematuria.
Yes, Yes, hematuria means red blood cells leaking out of bladder vessels by many reasons - infection, inflammation, stone, injury / trauma, tumors, kidney diseases, over-stretching of urinary tract,