INTRO TO MICROBIOLOGY

Transcription

1 INTRO TO MICROBIOLOGY Spring 2015 Peering through the microscope into a drop of seawater is like looking at stars with a telescope on a clear night. Dr. Gallardo, ocean researcher

2 What will you be studying in microbio? OBJECTIVES: What is microbiology? What are microbes? Several ways microbes affect our lives Brainstorm session Microbes - are organisms that are too small to be seen with the unaided eye Fun facts: Microbes account for more than 60% of all of Earth s organic maaer. Less than 1% of known microorganisms cause disease There are millions of different kinds of microbes A microbe isn t necessarily alive!

3 Microbes in Our Lives A few are pathogenic (disease- causing) West Nile, AIDS, mad cow, diarrhea, bacterial infecpons, etc.. Some are producers in the ecosystem by photosynthesis Produce industrial chemicals such as ethanol and acetone Produce fermented foods such as vinegar, cheese, and bread Produce products used in manufacturing (e.g., cellulose) and treatment (e.g., insulin, penicillin) Treat sewage and clean up pollutants

4 Where are the microbiologists?

5 Microbes in Our Lives Microbes are master recyclers! Take- in nutrients and inorganic elements that other life- forms can t use. They are the base of many food chains Cycle and recycle elements such as carbon, nitrogen, sulfur, hydrogen, oxygen, etc.. So that other plants and animals can use these nutrients. Allows humans to: Prevent food spoilage Prevent disease occurrence Many microbes in our body, keep us healthy! Microbes do much of your digespng for you.

6 Designer Jeans: Made by Microbes? Stone- washing: Trichoderma CoAon: Gluconacetobacter Debleaching: Mushroom peroxidase Indigo: E. coli PlasPc: Bacterial polyhydroxyalkanoate Applications of Microbiology, p. 3

7 Check Your Understanding Describe some of the destructive and beneficial actions of microbes. Awesome articles q 2015 will be the year of the microbiome! (Fortune magazine) q Are viruses alive?

8 GENERAL CHARACTERISTICS & IDENTIFICATION OF MICROBES Chapter 1.2

9 Types of Microorganisms (microbes) Figure 1.1

10 Two basic cell types & a virus

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12 Prokaryotic vs. Eukaryotic Cell Summary: Similarities: Plasma membrane, DNA, and cell wall (plant cells) Differences: 1. Eukaryotic DNA is in a nucleus surrounded by a nuclear membrane 2. Prokaryotic DNA is in a nuclear region not surrounded by a membrane 3. ProkaryoPc cells have a single circular chromosome; EukaryoPc cells have paired chromosomes 4. ProkaryoPc cells lack histone proteins; EukaryoPc cells have histone proteins 5. ProkaryoPc cell wall has peppdoglycan; plant and fungal cells have both cellulose and chipn

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14 Microbe Tree Microbes Viruses (acellular) Prokaryotes Eukaryotes Bacteria Archea Protists Fungi Algae Parasites (at young stage)

15 Monday homework Size estimate worksheet Read pg 1-11 & articles OBJECTIVES: Differentiate the major characteristics of each group of microorganisms: bacteria, archaea, fungi, protozoa, algae, viruses, and helminths Distinguish which groups of microbes are prokaryotes? Which are eukaryotes? List several ways in which microbes affect our lives. Name and define the primary areas included in microbiological studies.

16 Prokaryotes: Archaea Archaea single- celled Lack peppdoglycan Live in extreme environments Include Methanogens (produce methane as a waste product) Extreme halophiles (salty environments) Extreme thermophiles Archaea are not known to cause disease in humans Figure 4.5b

17 Prokaryotes: Bacteria Bacteria single- cell organisms PepPdoglycan cell walls Composed mainly of + Asexually reproduce by binary fission For energy, use organic chemicals, inorganic chemicals, or photosynthesis Many bacteria can swim using flagella Figure 1.1a

18 Eukaryotes: Protozoa Unicellular but EukaryoPc! Absorb or ingest organic chemicals May be mople via pseudopods, cilia, or flagella Can reproduce sexually or asexually Come in a variety of shapes Figure 1.1c

19 Eukaryotes: Fungi Examples of fungi: yeast, molds, and mildews Molds and mushrooms are mulpcellular, consispng of masses of mycelia (long filaments that branch and intertwine) Yeasts are unicellular ChiPn cell walls Use organic chemicals for energy Reproduce sexually or asexually Figure 1.1b

20 Eukaryotes: Algae Only 2 types of algae are microbes: Microbial green algae Red algae (live in ocean) phytoplankton Cellulose cell walls Use photosynthesis for energy Produce molecular oxygen and organic compounds Figure 1.1d

21 Acellular: Viruses Viruses are replicated only when they are in a living host cell Consist of DNA or RNA core Core is surrounded by a protein coat Coat may be enclosed in a lipid envelope Figure 1.1e

22 Check Your Understanding Which groups of microbes are prokaryotes? Which are eukaryotes? 1-3

23 Basic Cell Types Prokaryote: single- celled organisms, and all are bacteria or archaea. Eukaryote: single- celled or multi- cellular organisms Pro = before Eu = true Karyon = nucleus