The bladder neck.
D006801:Humans; D006984:Hypertrophy; D008297:Male; D011470:Prostatic Hyperplasia / Q000502:physiology*; D001743:Urinary Bladder / Q000502:physiology*; D014553:Urinary Tract Physiological Phenomena; D014555:Urination Disorders
BLADDER/physiology; PROSTATE HYPERTROPHY/physiology; URINATION DISORDERS