Describe the process of urine formation in kidneys.

(N/A) Urine formation in the kidneys occurs through three main processes:
$1$. Glomerular Filtration: Blood enters the glomerulus under high pressure,where water,glucose,amino acids,and nitrogenous wastes are filtered into the Bowman's capsule.
$2$. Tubular Reabsorption: As the filtrate passes through the renal tubule,essential substances like glucose,amino acids,salts,and a significant amount of water are reabsorbed back into the blood capillaries.
$3$. Tubular Secretion: Certain substances like potassium ions,hydrogen ions,and some drugs are actively secreted from the blood into the filtrate to maintain the ionic balance and $pH$ of the body fluids.