When they are stronger and last longer
The important structure of the urinary system is:
The kidneys, ureters, bladder, and urethra are the primary structures of the urinary system. they filter blood and remove waste from the body in the form of urine. The size and position of lower urinary structures vary with male and female anatomy.
Hope this helped
I'm almost positive that this is DNA. LMK if I'm correct.
