biology
.... The second group is the Amoebae, which can be subdivided into the testate amoebae, which have a shell-like covering, and the naked amoebae, which don't have this covering. Finally, the third group is the Flagellates, which are generally the smallest of the protozoa and have one or several long, whip-like projections called flagella poking out of their cells. The last Neanderthals thought to remained lives about 400,000 years ago just before the ice age. Although early modern humans expanded throughout Eurasia some time between 30,000 and 40,000 years ago, not enough evidence yet exists to prove where they originated or how extensive their expansion may have been. Perhaps Neanderthals in some areas were replaced by modern humans, while those in other regions evolved into modern humans on their own. There are 5 different systems. The digestive, circulatory, excretory, reproductive, and respiratory. The digestive system prepares food for use by hundreds of millions of body cells. It consists of the mouth, esophagus, stomach, small intestine, and large intestine. The circulatory system c...