REPRODUCTIVE SYSTEM

Viagra can also cause vision problems. An erection squeezes the veins shut so the blood can’t leak out. If Viagra (or anything else) causes an erection for longer than four hours, the erection decreases the blood flow, and the tissue is killed. This is a complex organ system; lots of plumbing issues. 2. SCROTUM . A. TESTICLES. makes sperm. B ... ................
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