Piss sex dates
The physiology of micturition and the physiologic basis of its disorders are subjects about which there is much confusion, especially at the supraspinal level.
Micturition is fundamentally a spinobulbospinal reflex facilitated and inhibited by higher brain centers such as the pontine micturition center and, like defecation, subject to voluntary facilitation and inhibition.
Fibers in the pelvic nerves constitute the main afferent limb of the voiding reflex; the parasympathetic fibers to the bladder that constitute the excitatory efferent limb also travel in these nerves.
Part of the urethra is surrounded by the male or female external urethral sphincter, which is innervated by the somatic pudendal nerve originating in the cord, in an area termed Onuf's nucleus.
During the storage phase the internal urethral sphincter remains tense and the detrusor muscle relaxed by sympathetic stimulation.
During micturition, parasympathetic stimulation causes the detrusor muscle to contract and the internal urethral sphincter to relax.
It is normal for adult humans to urinate up to seven times during the day.In healthy individuals, the lower urinary tract has two discrete phases of activity: the storage (or guarding) phase, when urine is stored in the bladder; and the voiding phase, when urine is released through the urethra.The state of the reflex system is dependent on both a conscious signal from the brain and the firing rate of sensory fibers from the bladder and urethra.Brain centers that regulate urination include the pontine micturition center, periaqueductal gray, and the cerebral cortex.In placental mammals, urine is drained through the urinary meatus, a urethral opening in the male penis or female vulval vestibule.