Facts on File Encyclopedia of Health and Medicine

germ cells in the seminiferous tubules. Specialized
cells called Sertoli cells nourish and protect the
new sperm cells, ushering them into the epi-
didymis where they grow to maturity as they
migrate through the 10 to 12 feet of tightly coiled

tubule that makes up this testicular structure.

Their journey takes sperm to the ejaculatory

ducts, where they mix with SEMEN. A mature sper-

matozoon consists of a head (the cell body) con-

taining genetic material and a whiplike tail that

sperm 341

SEXUALLY TRANSMITTED DISEASES (STDS)

STD Cause Symptoms Treatment and Outlook
CHLAMYDIA BACTERIA: Chlamydia often no symptoms; men may treatable and curable with antibiotic
trachomatis have discharge from PENISand medications
burning with URINATION; women
may have vaginal discharge

GENITAL HERPES VIRUS: HERPES SIMPLEX 2 burning, itching, chancrelike sores; not curable but symptom relief with
(HSV-2) vaginal discharge in women; ANTIVIRAL MEDICATIONS
burning with urination in men

GONORRHEA bacteria: Neisseria often no symptoms; burning with treatable and curable with antibiotic
gonorrhoeae urination and discharge from the medications though some strains are
penis in men; vaginal discharge resistant
in women

HEPATITISB virus: hepatitis B JAUNDICE, FEVER, NAUSEA, VOMITING, preventable with hepatitis B VACCINE
virus (HBV) swollen and tender LIVER postexposure prophylaxis

hepatitis C virus: hepatitis C jaundice, fever, nausea, vomiting, postexposure prophylaxis
virus (HCV) swollen and tender liver

HIV/AIDS virus: human flulike symptoms when INFECTION not curable and ultimately fatal;
immunodeficiency occurs; typically no symptoms antiretroviral drugs can keep the virus in
virus (HIV) until AIDS emerges check for delay of disease manifestation
and remission of symptoms

HUMAN virus: human often no symptoms; may cause not curable though infection often runs its
PAPILLOMAVIRUS papillomavirus (HPV) genital warts course in several years; various methods
(HPV) to remove warts; some strains associated
with CERVICAL CANCER

nongonorrheal bacteria: various burning with urination; discharge treatable and curable with antibiotic
URETHRITIS from the penis in men medications

SYPHILIS bacteria: Treponema painless chancre that may be treatable and curable with antibiotic
pallidum unnoticeable; SKIN RASH; fever; medications
late stage symptoms often systemic

TRICHOMONIASIS PROTOZOA:Trichomonas foul-smelling, discolored discharge; treatable and curable with metronidazole
vaginalis painful urination in men; vaginal or
vulvar itching or burning in women