The Differences Between Eukaryotic And Prokaryotic Cells

1910 Words8 Pages
Organisms are made up of cells which were considered as the basic unit of life. After the invention of microscope, Robert Hooke first discovered cells by looking at a dead cell from an oak tree. His finding brought the study of cell biology. According to the cell theory formulated by lots of scientists, all living organisms are composed of at least one cell which is the basic unit of life, and all cells come from pre-existing living cells. Cell is a wide type of substance that have variations between species and species, for example a plant cell contains a cell wall which is absent in most animal cells. Scientists had been trying to classify all organisms into different groups. Current classification system is the three domains and six kingdoms which the three domain divides organisms based on the ribosomal RNA they contained in the cells. The three domains are Bacteria, Archaea and Eukarya which the first two are made up of prokaryotic cells and Eukarya is made up of eukaryotic cells. This essay will focus on the differences between eukaryotic and prokaryotic cells. To start with, the first eukaryotic and prokaryotic cell appeared at different time mainly because to their requirements for survive. At first the condition of the Earth was not suitable for any organism, for example lack of organic molecules. After the modification of the Earth environment, the prokaryotic cells in single-celled organisms were believed to arise 3.5 billion years before. The oldest fossils of
Open Document