Two units (equivalent to two years or four semesters) of laboratory science are required (three units are strongly recommended), providing fundamental knowledge in two of the following disciplines: 1  Biology. 2  Chemistry. 3  Physics.
Slave forts were established all along the coast of West Africa, to house captured Africans in holding pens (barracoons) awaiting transport. They were equipped with up to a hundred guns and cannons to defend European interests on the coast, by keeping competitors at bay. There were approximately 80 castles dotted along the slave-trading coast.
The Placozoa are an animal phylum, a primitive form of invertebrate. They are the simplest in structure of all metazoa. The Placozoa is usually considered to have only one species, Trichoplax adhaerens, but there is enough genetic diversity that it is possible that there are multiple, morphologically similar species. Although they were first discovered in 1883, a common name does not exist for the taxon.