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.
Myth One. Myth: AIDS is mostly an African problem. Fact: Of the 42 million people around the world who live with HIV/AIDS, 70% are in sub-Saharan Africa. HIV/AIDS exists and is spreading in Africa in a socioeconomic context created by western colonialism and, more recently, western trade and economic policies.
Because primates are suspected of being the source of HIV, AIDS is considered a zoonosis, an infection that is shared by humans and other vertebrate animals. Genetic studies of a pandemic strain of HIV, known as HIV-1 group M, have indicated that the virus emerged between 1884 and 1924 in central and western Africa.