Final answer:
A Urethrotomy is the surgical procedure to enlarge the opening of the external urethra, often done to address urethral obstructions or strictures.
Step-by-step explanation:
An incision made to enlarge the opening of the external urethra is called a Urethrotomy. This procedure is often used to address urethral strictures or blockages, by cutting into the urethra to remove or reduce the narrow section. The female urethra is notably shorter than the male urethra, which means it is less of a barrier for bacteria and explains why women are more prone to urinary tract infections (UTIs).
The male urethra, on the other hand, is longer, averaging about 20 cm and is divided into four regions: the preprostatic, prostatic, membranous, and spongy urethra. It passes through several structures, including the prostate gland, and serves dual functions including excretion of urine and ejaculation of semen.
The urinary bladder, which is involved in the storage of urine before it is expelled through the urethra, exhibits differences between males and females largely due to the presence of the uterus in females and the prostate in males.