â¢ Medium-grained (1/16 mm to 2 mm) rocks are usually called sandstone. Medium-grained rocks can be composed of quartz grains, feldspar grains (arkose), or rock fragments and clay (graywacke). Sandstone (Photograph by Parvinder Sethi). Medium-sized grains in clastic sedimentary rocks form sandstone. This sample is a quartz sandstone.
Eukaryotes are those organisms in which the cell body contains a nucleus whereas prokaryotes are those organisms in which the cell body does not contain a nucleus. In amoeba, the reproduction is carried out under the instruction of the nucleus thus making it a eukaryote organism.
DNA in pro-/eukaryotes. Cells are the basal unit of all living organisms (except virusses, but these are not true, independently living organisms). There are two kinds of cells on the earth: types of cells: prokaryotic cells and eukaryotic cells (eu = true; karyon = nucleus, pit).n eukaryotic cells, like in the maize cell shown here, DNA is located in the nucleus, the mitochondria and the chloroplasts (occuring only in plants and some protists).