Describe some of the destructive and beneficial actions of microbes.
destructive: pathogenic; spoil foods;
soil microbes break down wastes; beneficial: photosynthesis, digestion and synthesis of vitamins; produce acetone and butanol; produce foods; make jeans;
1-2 Recognize the system of scientific nomenclature that uses two names:
a genus and a specific epithet (species)
Distinguish a genus from a specific epithet.
a genus: Capitalized and
a specific epithet (species): not capitalized
1-3 Differentiate the major characteristics of each group of microorganisms.
Bacteria - simple, single-celled organisms, DNA not enclosed, Prokaryotic, peptidoglycan cell wall, binary fission (split into 2 equal parts), contain flagella
Archaea - prokaryotic, peptidoglycan cell wall, found in extreme environments; pathogenic in humans
Fungi- Eukaryotic, nucleus containing DNA, uni/multi cellular, photosynthesis, chitin cell wall, sexually or asexual repoduction
Protozoa - unicellular, eukaryotic, move using pseudopods, flagella or cilia, photosynthesis, sexual/asexual reproduction
Algae - eukaryotic, photosynthetic, unicellular, cellulose cell wall.
Viruses - acellular, simple, one type of nucleic acid, must have host to survive.
Multicellular Animal Parasites/Helminths - eukaryotic, (flat/round worms)
1-5 Explain the importance of observations made by Hooke and van Leeuwenhoek.
He discovered life's smallest structural units called 'cells'; discovered live microorganisms
1-6 Compare spontaneous generation and biogenesis.
Belief that some forms of life could arise spontaneously from nonliving matter;
What evidence supported spontaneous generation?
Redi's experiment with one covered and one uncovered meat jar producing maggots proved that this could not occur spontaneously
3-1 List the metric units of measurement that are used for microorganisms. How long is it in nanometers?
3-3 Define total magnification and resolution. What does it mean when a microscope has a resolution of 0.2 nm?
3-4 Identify a use for darkfield, phase-contrast, differential interference contrast, fluorescence, confocal, two-photon, and scanning acoustic microscopy, and compare each with brightfield illumination.
4-1 Compare and contrast the overall cell structure of prokaryotes and eukaryotes.
Compare: both contain nucleic acids, proteins, lipids, and carbs; same chemical reactions to metabolize food, build proteins, and store energy.
Contrast: structure of cell walls and membrane, and absence of organelles
What is the main feature that distinguishes prokaryotes from eukaryotes?
Prokaryotes: DNA not enclosed, singular arranged chromosomes, DNA not associated with histones, lack membrane-enclosed organelles, cell wall contain polysaccharide peptidoglycan, divide by binary fission
Eukaryotes: DNA in nucleus, muti chromosomal, histones, membrane-enclosed organelles, cell wall simple, mitosis
4-2 Identify the three basic shapes of bacteria.
coccus- round, bacillus- rod shaped, spiral- spiral
4-3 Describe the structure and function of the glycocalyx.
sugar coat surrounding a cell. made of viscous (sticky), gelatinous polymer that is externa to the cell wall. composed of polysaccharide, polypeptide, or both.
-organized and firmly attached to cell wall: capsule
-unorganized and loosely attached: slime layer
Why are bacterial capsules medically important?
capsules protect pathogenic bacteria from phagocytosis by the cells of the host
4-4 Differentiate flagella, axial filaments, fimbriae, and pili.
Flagella: prokaryotic cells; long filamentous appendages that propel bacteria
Axial filaments: found on spirochetes; bundles of fibrils that arise at the ends of the cell beneath an outer sheath and spiral around the cell/spiral motion
Fimbriae: involved in forming biofilms; help bacteria adhere to epithelial surfaces
Pili: motility and DNA transfer (conjugation)
4-5 Compare and contrast the cell walls of gram-positive bacteria, gram-negative bacteria, acid-fast bacteria, archaea, and mycoplasmas.
Gram positive: many layers of peptidoglycan, thick, rigid structure; contain teichoic acids
Gram negative: thin layer of peptidoglycan, outer membrane made of lipopolysaccharides, lipoproteins, and phospholipids.
Acid-fast bacteria: high concentration of hydrophobic waxy lipid (mycolic acid), thin layer of peptidoglycan
Archaea: may have no cell wall, or unusual walls of polysaccharides and proteins- no peptidoglycan.
Mycoplasmas: no cell wall
Why are drugs that target cell wall synthesis useful?
Bacterial cell walls are made of different material as Eukaryotic cells
4-7 Differentiate protoplast, spheroplast, and L form.
Protoplast: a gram-positive bacterium or plant cell treated to remove the cell wall
Spheroplast: gram-negative bacterium treated to damage the cell wall; spherical cell
L form: prokaryotic cell that lack a cell wall; can return to walled state
4-9 Define simple diffusion, facilitated diffusion, osmosis, active transport, and group translocation.
4-18 Define organelle. Compare the structure of the nucleus of a eukaryote and the nucleoid of a prokaryote.