1 / 21

Introduction to Microorganisms

Introduction to Microorganisms. 1. Lesson Objectives:. Define microbiology. List the organisms included in the field of microbiology . Discuss the role microorganisms play in the environment, the food industry and the medical field.

zalman
Télécharger la présentation

Introduction to Microorganisms

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to Microorganisms 1

  2. Lesson Objectives: • Define microbiology. • List the organisms included in the field of microbiology . • Discuss the role microorganisms play in the environment, the food industry and the medical field. • List the distinguishing characteristics of bacteria, fungi, algae, protozoa and viruses. • Describe how bacteria are named. • List the microorganisms that are classified as prokaryotes and eukaryotes.

  3. Microbiology The study of living organisms too small to be seen with the naked eye. Question: (with a partner) What event, discovery, or invention marked the start of Microbiology? Answer:________________________________

  4. Members • Bacteria • Fungi (yeasts and molds) • Protozoa • Algae • Viruses

  5. Prokaryote Cell

  6. Cellular Organization • Prokaryotes-Pre nucleus • Bacteria • Simple cells • Small • No membrane- bound nucleus. DNA is organized into one large circular strand (genome) and smaller circles (plasmids) • No membrane-bound internal structures (ribosomes present) • Cell division quick-Binary Fission

  7. Eucaryote

  8. Eukaryotes • True (good) nucleus • Membrane bound organelles • Includes fungi, algae, and protozoa, plants and animals • More structurally complex • Cell Division is by mitosis and meiosis

  9. Microbes and the Planet • First life on the earth • Prokaryotes (bacteria) appeared about 3.5 billion years ago • Eukaryotes ( all other microbes) arose 2 billion years ago • Ubiquitous • Adaptable to any niche that exists

  10. Microbes and the Planet • Essential for life • Photosynthesis • Microbes are responsible for over 70 % of Earth’s photosynthesis • First photosynthesis—did not produce oxygen! When oxygen was formed, an environment suitable for man and animals resulted. Earth’s environment is a result of microbial products soil water atmosphere

  11. Scope of Microbiology • Environmental • Most microbes are beneficial • Genetic engineering • Bioremediation • Food production • Symbionts—provide necessary processes to other organisms.

  12. Microorganisms and the Environment • Decomposition- recyclers of nutrients • Can breakdown complex organic compounds to simple compounds • Return CO2N2, and H20 to atmosphere and soil

  13. Scope • Food Microbiology Examples of food made possible by microbes:

  14. Microbes and Man Normal flora Pathogens Approximately what percentage of microbes are pathogens? Found in which parts of body?

  15. Medical Antibiotics fungus Why is there a clear zone here? Figure 1.5

  16. Classification and Nomenclature Names were originally based on visible characteristics of microbes: Microscopic appearance (Staphylococcus—”bunch of grapes,” Bacillus—”rod”) Discoverer of the organism or the disease (Salmonella: Daniel Salmon, Listeria: Joseph Lister) ??????????? (Pseudomonas: “false monad”)

  17. Taxonomy: Organizing, Classifying and Naming Living Things • Formal system originated by Carl von Linné (1701-1778) • Concerned with: • classification – orderly arrangement of organisms into groups • nomenclature – assigning names • identification – discovering and recording traits of organisms for placement into taxonomic schemes

  18. Woese System of Classification Carl Woese compared a macromolecule found in all cells (rRNA) and used the sequence of bases in this molecule as a basis of comparison in thousands of organisms.

  19. Why use ribosomal RNA • Every organism on the planet has rRNA, and it always has the same function. • The sequence of nucleotides (adenine, guanine, cytosine, uracil) in certain parts of rRNA undergo very little change throughout evolution. Therefore… • All members of a given species have the same rRNA sequence (in certain areas).

  20. Woese’s conclusion • Three major “domains” of living cells:BacteriaArchaeaEukarya • The first two are prokaryotes, the third is all eukaryotes • Bacteria and Archaea are as different from each other as each is from Eukarya

  21. Nomenclature • Binomial • Latinized • Genus-noun • Species-adjective • Genus (always capitalized) species (never capitalized) • Staphylococcus aureus • S. aureus • S. epidermidis

More Related