Final answer:
The external urethral sphincter is the voluntary skeletal muscle that provides control over urine release. It is part of the somatic nervous system and works in conjunction with the detrusor muscle during the process of urination.
Step-by-step explanation:
The skeletal muscle surrounding the urethra that provides voluntary control of urine release is known as the external urethral sphincter. This muscle is a striated muscle controlled by the somatic nervous system, allowing individuals to consciously control the release of urine. This voluntary control is possible due to the intricate operation of nerves, including the hypogastric, pelvic, and pudendal nerves. The external urinary sphincter is integral in maintaining continence as the bladder fills and during the act of micturition, or urination. Upon reaching a certain volume of urine in the bladder, afferent nerves signal to the brain the need to void, but the decision to urinate and relax the sphincter is a conscious one. Moreover, as the bladder's detrusor muscle contracts during urination, aided by the release of acetylcholine from cholinergic neurons, the external sphincter must relax to allow urine to flow through the urethra and out of the body.
The ability to control this muscle can weaken with age or due to certain medical conditions, leading to incontinence. However, the detrusor muscle also plays a vital role in the process, as it must contract for urine to exit the bladder. The sphincter's importance is underscored by the need to maintain urinary continence as well as ensuring proper voiding when necessary.