Mesoderm lining the coelom forms mesothelium. Separation of Peritoneal and Pleural Cavities: In the adult, peritoneal and pleural cavities are separated by the diaphragm. The diaphragm isformed by a septum transversum, paired pleuroperitoneal folds, and somatic mesoderm.
HIV Myth 2: 'HIV and AIDS Are the Same Thing'. Absolutely not. HIV is the virus that infects a person and attacks the immune system. AIDS is the disease that develops later in people with HIV that remain untreated or don't respond to treatment.
MYTH: AIDS is not caused by HIV. DEBUNKING: This is the biggie, of course. As long ago as 1983, researchers first isolated HIV from people with AIDS. By 1985, they had developed a test showing that the overwhelming majority of people with AIDS have antibodies to HIV in their blood.