As blood enters the kidneys everything except what is filtered out?

Answer 1

The kidneys are concerned with urine production, which is done to to regulate the contents of the internal environment. The functional unit of the kidney is called the nephron. At the start of the nephron is a structure called Bowman capsure. This structure takes the filtrates out of the blood from a convoluted cappillary network called the glomerulus. Very much of the contents of the plasma is filtered, only leaving Red Blood Cells and plasma proteins which are both to big to be filtered. As the filtrate passes along the nephron most of its contents are removed back into the blood. The contorl of what is in the urinr comes mostly from this reabsorption, not the initial filtration, and it might be interesting to note that up to 50% of the urea is reabsorbed back into the blood not all goes into the urine.

so in a nutshell ? can someone please make this more general ???

Plasma proteins, cells and platelets are too large to pass through the membrane; they remain in the blood. :D