Essay on Archaea VS Bacteria

[1] – Molecular Cell Biology, 7th edition 2012, Harvey Lodish, Chris A. Kaiser, Anthony Bretscher, et al. Macmillian Higher Education.

When life arose on Earth about 4 billion years ago, the first types of cells to evolve were prokaryotic cells. For approximately 2 billion years, prokaryotic-type cells were the only form of life on Earth. The oldest known sedimentary rocks found in Greenland are about 3.8 billion years old. The oldest known fossils are prokaryotic cells, 3.5 billion years in age, found in Western Australia and South Africa. The nature of these fossils, and the chemical composition of the rocks in which they are found, indicates that these first cells made use of simple chemical reactions to produce energy for their metabolism and growth. Eukaryotic cells evolved into being between 1.5 and 2 billion years ago. Eukaryotic cells appear to have arisen from prokaryotic cells, specifically out of the archaea. Indeed, there are many similarities in molecular biology of contemporary archaea and eukaryotes. However, the origin of the eukaryotic organelles, specifically chloroplasts and mitochondria, is explained by evolutionary associations between primitive nucleated cells and certain respiratory and photosynthetic bacteria, which led to the development of these organelles and the associated explosion of eukaryotic diversity. Today Prokaryotes

Cytoplasmic streaming was measured 4 times after flushing the cells with pond water, at 5 minute intervals

Currently, there are two major competing theories for the endosymbiotic origin of eukaryotic cells. The first theory claims that the eukaryotic cell is a combination of an archaeon with a

Wischusen, William, Jolissaint, Ann, Reiland, Jane, and Pomarico, Steven. 2012. Biology 1208/1209: Biological Laboratories for Science Majors. Hayden McNeil, Plymouth,

Prior to the development of DNA technology and the sequencing of organismal genomes, Charles Darwin suggested that the “tree” of life can be traced back to a single root (Koonin and Wolf, 2012). While Darwin’s theory was primitive, it laid the groundwork for the phylogenetic trees that are currently studied in science classrooms around the world. The three-domain tree, containing Eukarya, Archea, and Bacteria, soon became too simplistic due to the realization that some bacteria possessed the ability to exchange genetic information by horizontal gene transfer (Koonin and Wolf, 2012).

If necessary, use the back of the exam pages for the rest of your answers. Do not use other sheets of paper. Please write legibly; if I cannot read your answer, I will count it wrong.

You may use the lab manual, pre-lab lectures, and credible internet resources, however you may not use your cell bio lab classmates as a resource. You will most likely see this material again on the Final and I highly encourage you to work individually and seek help from myself or your TA. Plagiarism will result in an automatic zero.

Molecular Cell Biology, 7th Edition, 2013, Lodish, Berk, Kaiser, Krieger, Bretscher. Ploegh, Amon, and Scott. W.H. Freeman and Company (ISBN-13: 978-1-4292-3413-9)

Bacteria and Archaea are prokaryotic, which are mostly single-celled incomplex microorganisms. Both Bacteria and Archaea have a variety of prokaryotes classified in multiple kingdoms (Reece, et al., Campbell Biology, 2014). There are a number of scientists who believe that Archaea cells may be the precursor to Eukaryotic cells and that they have more in common with Eukaryotes than Prokaryotes (Madigan, Martinko, & Dunlap, 2009).

Bacteria have several different types of pili, known and classified based on their structure and assembly. Similarly, archaea have different appendages that

3. Tortora GJ. Functional Anatomy of Prokaryotic and Eukaryotic Cells. In: Microbiology an Introduction. 9th ed. San Francisco, CA: Pearson Education, Inc; 2007: 77-113.

Prokaryote cells - bacteria and archeans. They are single celled organisms, where the DNA is not separate from the cytoplasm. These prokaryote cells formed the earliest and most primitive life on earth.

Eukaryotes come in two grades of organization: single-celled (protists) and multicellular (plants, animals, and fungi). The world today is full of complex multicellular plants and animals: how, why, and when did they evolve from protists?

Although both Archaeal and bacterial cells possess flagella for motility, the composition of each organism’s flagellum is very different. In bacterial cell, the flagellum is composed of a basal body, external protein filaments both are joined together by a third component called the hook.(Bacteria Flagella David Gene Morgan , Shahid Khan). In Archaeal, the protein filament is polymerised, glycosylated and very much thinner. The Archaeal flagellum is believed to be similar to the bacteria IV pilus in structure.(www.uniprot.org/keywords/974).