Final answer:
The somatic nervous system is responsible for the voluntary control of the external urethral sphincter, which allows for the conscious regulation of urination.
Step-by-step explanation:
To voluntarily control urination, the somatic nervous system innervates the external urethral sphincter.
The process of controlling urination involves a complex interaction between the autonomic and somatic nervous systems. The autonomic system manages the involuntary actions of the detrusor muscle, which relaxes as the bladder fills, while the somatic nervous system provides voluntary control over the external urethral sphincter. This sphincter is made up of striated muscle, which is under conscious control, enabling individuals to hold urine until they decide to release it. The control of urination is also influenced by other nerves such as the hypogastric, pelvic, and pudendal nerves, which play roles in the complex coordination of bladder filling and emptying.
The external urethral sphincter is a striated muscle that controls the voluntary control of urination, allowing the urine to leave the body through the external urethral orifice. This sphincter is innervated by the somatic nervous system, which means it is under conscious control.