It's actually pretty easy to estimate the first number - all you have to know is the apparent angular size of the sun and moon in the sky (about half a degree each) and the the time it takes the moon to orbit the earth (about one month).
Eukaryotic Organelles. 1  Nucleus-a membrane bound structure that contains the cell's hereditary (DNA) information and controls the cell's growth and reproduction. 2  It is commonly the most prominent organelle in the cell.
Cell Membrane. 1  The cell membrane forms the outer boundary of the cell. 2  The cell membrane is composed of a double layer of lipid molecules in which proteins float.