• Chlamydia, gonorrhea, and syphilis are sexually transmitted diseases caused by bacteria.
• Some sexually transmitted diseases may be asymptomatic; yet leaving them untreated can lead to serous health consequences.

1. Why are chlamydia infections particularly troublesome?
   Answer
2. What kinds of complications can accompany gonorrhea?
   Answer
3. What are the three stages of syphilis?
   Answer

Essential Study Partner

• Chlamydia

• Genital warts, herpes, hepatitis B and AIDS are sexually transmitted diseases caused by viruses.
• Genital herpes may be transmitted even if there are no apparent symptoms of the disease.
• There is no cure for sexually transmitted viral infections.

1. Can the herpes virus be transmitted even if a partner has no symptoms at the time?
   Answer
2. Genital warts are associated with what other medical condition in women?
   Answer
3. What organ in the body is most affected by a hepatitis infection?
   Answer

• Trichomoniasis is sexually transmitted disease caused by a protozoan.
• A fungus is the cause of one form of vaginitis, an infection of the vagina.
• Many different types of animals cause infections in humans. Pubic lice are sexually transmitted.

1. Can pubic lice be transmitted other than by sexual interactions?
   Answer
2. How common is bacterial vaginosis, and what are the possible consequences of an infection?
   Answer
3. What are the symptoms of trichomoniasis, and why should it be treated?
   Answer

Animation Activity

• Trichomonas

• AIDS is caused by a Human Immunodeficiency Virus (HIV)
• Over 36 million people are estimated to living with an HIV infection.
• New HIV infections are increasing faster among heterosexuals than homosexuals.
• There are three successive phases of an HIV infection.
• A person with AIDS dies from an opportunistic infection.

1. How many people in the world currently have an HIV infection? What continent is particularly affected?
   Answer
2. What are the three categories of an HIV infection?
   Answer
3. What treatments are currently available for an HIV infection?
   Answer

Animation Activity

• HIV Replication
• HIV Replication(English)
• HIV Replication(Spanish)
• Treatment of HIV(English)
• Treatment of HIV(Spanish)
• How the HIV Infection Cycle Works
• How the NAD+ Works
• proton Pump
• The Calvin Cycle

Reading

• The HIV/AIDS Epidemic: A Scientist's Perspective