Normal urine from a healthy person can be expected to contain all of the following except

A. distractor: There is no muscle in human anatomy with this specific designation. This term is likely a distractor intended to confuse the reader with the similar-sounding name of the actual bladder muscle. Muscle nomenclature usually reflects the function, location, or orientation of the fibers, which is not represented by this term.

B. detrusor: This consists of three layers of smooth muscle fibers arranged in inner longitudinal, middle circular, and outer longitudinal orientations within the bladder wall. During micturition, the parasympathetic nervous system stimulates the detrusor to contract, which increases internal pressure to expel urine. It remains relaxed during the storage phase to allow for bladder filling.

C. corpus spongiosum: This is a column of erectile tissue located in the male penis that surrounds the spongy urethra. Its primary function is to prevent the urethra from being pinched shut during an erection, ensuring that semen can be ejaculated. It is a vascular structure rather than a muscular component of the urinary bladder.

D. cremaster: This is a skeletal muscle found in the spermatic cord and scrotum of males. It functions to elevate the testes toward the body cavity in response to cold or sexual arousal to regulate testicular temperature. It is not located within the pelvic viscera or the walls of the urinary bladder.

A. enhanced sodium ion loss in urine: Increasing the excretion of sodium would not address the underlying hydrogen ion excess or bicarbonate deficit. In fact, the kidneys typically attempt to retain sodium to maintain blood volume during the fluid loss associated with diarrhea. Electrolyte loss is a consequence of the illness rather than a corrective compensatory mechanism for pH.

B. increased respiratory rate and depth: The body compensates for metabolic acidosis by stimulating peripheral chemoreceptors to increase alveolar ventilation. This process, known as Kussmaul breathing, enhances the elimination of carbon dioxide from the blood. Reducing partial pressure of carbon dioxide shifts the carbonic acid-bicarbonate buffer equation to decrease the concentration of free hydrogen ions.

C. increased renin secretion: Renin secretion is a response to decreased blood pressure and volume resulting from fluid loss in diarrhea. While the subsequent production of aldosterone helps regulate electrolytes and blood pressure, it is not the primary mechanism for correcting systemic pH. Renin serves a hemodynamic rather than an immediate acid-base compensatory function.

D. hypoventilation: Decreasing the rate and depth of breathing would cause the retention of carbon dioxide, leading to an increase in carbonic acid. This would result in respiratory acidosis, which would exacerbate the existing metabolic acidosis instead of correcting it. Hypoventilation is a compensatory response for metabolic alkalosis, not acidosis.