Every day, a few liters of fluid seep out of your capillaries into your tissues. The lymphatic system collects it, filters it through lymph nodes, then returns it to the blood. But no organ pumps it: lymph moves thanks to your muscle contractions, breathing and one-way valves. Moving your body keeps lymph flowing.
Every day, your kidneys filter around 180 liters of blood plasma, about a bathtub's worth. Yet you only have about 3 liters of plasma, so it passes through your kidneys some sixty times a day. Over 99% of the filtered water is reabsorbed, leaving just one to two liters of urine.
A 70 kg adult is made of about 7 × 10²⁷ atoms, or seven billion billion billion. The observable universe is thought to hold on the order of 10²² to 10²⁴ stars. Even with the high estimate, you contain thousands of times more atoms than there are stars in the entire visible cosmos.