From their formation to ejaculation, sperm cells take the following pathway:

B. true: Approximately 60 to 70 percent of semen volume is produced by the seminal vesicles, while 25 to 30 percent comes from the prostate gland. The sperm cells, along with a small amount of fluid from the epididymis, constitute only about 10 percent of the final ejaculate. This ensures the sperm are suspended in a protective, nutritive medium.

A. decrease the production of aldosterone: Angiotensin 2 serves as the primary secretagogue for the zona glomerulosa of the adrenal cortex. It directly stimulates the synthesis and release of aldosterone to enhance sodium retention. Increasing aldosterone is a vital step in the homeostatic response to low blood pressure.

B. decrease water absorption: This effector molecule promotes water retention by stimulating thirst centers in the hypothalamus and increasing the release of antidiuretic hormone. It also enhances sodium reabsorption in the proximal tubule, which creates an osmotic gradient for water. These actions collectively increase total body water volume.

C. decrease arterial blood pressure: Angiotensin 2 is one of the most potent endogenous vasoconstrictors known in human physiology. Its primary systemic effect is to increase peripheral resistance and venous return to elevate blood pressure. Decreasing pressure would contradict the corrective goals of the renin-angiotensin-aldosterone system.

D. constrict arterioles and increase blood pressure: By binding to AT1 receptors on vascular smooth muscle, angiotensin 2 induces rapid systemic vasoconstriction. This increases systemic vascular resistance and immediately raises arterial blood pressure to maintain organ perfusion. It specifically targets the efferent arterioles to maintain glomerular filtration during hypotension.

E. increase the production of ADH: While angiotensin 2 does stimulate the posterior pituitary to release antidiuretic hormone, choice D is the most direct and comprehensive description of its primary cardiovascular function. ADH works synergistically with angiotensin 2 to restore blood volume and pressure. Both are essential for long-term hemodynamic stability.