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BACTERIA The Prokaryotes: Eubacteria and Achaea. SBI3U Biology. Dr. Oz (4:37 min): http://www.youtube.com/watch?v=CljhLb1Ar9U Toilet germs (1:53 min): http://www.youtube.com/watch?v=v6nGgS6ADoI&feature=related
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BACTERIAThe Prokaryotes:Eubacteria and Achaea SBI3U Biology Dr. Oz (4:37 min): http://www.youtube.com/watch?v=CljhLb1Ar9U Toilet germs (1:53 min): http://www.youtube.com/watch?v=v6nGgS6ADoI&feature=related Cell Phones! (3:01 min): http://www.youtube.com/watch?v=4lmwbBzClAc&feature=related
Learning Objectives: • Learning Goals • Minds ON • Bacteria PowerPoint • Micro viewers lab • Exit card
Learning Goals We are / will be learning to… • Analyze the risks and benefits of human intervention (e.g. pesticide use, fish stocking, tree planting, etc.) • Analyze how climate change could impact the diversity of living things (e.g. Global warming, increase in precipitation) • Become familiar with terms such as: species diversity, structural diversity, bacteria, fungi, binomial nomenclature, morphology • Classify, apply, and draw dichotomous keys to identify and classify organisms according to kingdom • Explain concepts of taxonomic rank such as genus, species and taxon • Compare/contrast characteristics of prokaryotes, eukaryotes and viruses • Compare/contrast anatomical and physiological characteristics of organisms representative of each kingdom • Explain structural and functional changes of organisms as they have evolved over time • Explain why biodiversity is important for maintaining viable ecosystems
Minds ON • Read from Bill Bryson’s “A Short History of Nearly Everything”
Yesterday’s Recap Dichotomous Keys: A tool used to classify organisms based on structural characteristics (≠ colour, where an organism lives, etc.) Refresher: a prokaryote = Kingdom Archaebacteria and Eubacteria = all bacteria * Can we think of a mental reminder for this?
Bacteria Cell See Fig. 6 on page 48 in text.
Important Structures: • Capsule • Cell wall – made of peptidoglycan and outer membrane • Plasma membrane • Nucleoid region – condensed DNA molecule • Ribosomes in the cytoplasm • Pili (Singular = Pilus) • Flagellum
Characteristics of BacteriaProkaryotic Cells: unicellular (single-celled) no nuclear membrane or other membranes around organelles small—less than 2 µm (micrometers) only 1 circularchromosome (plasmid)
Identifying Prokaryotes Cell Shape Cell Wall Movement
Bacterium Shapes And Groupings SHAPES Coccus~ Sphere shaped bacteria Bacillus~ Rod shaped bacteria Spirillium ~ Spiral shaped bacteria GROUPINGS Mono - one Diplo - two Strepto - in a chain Staphylo - cluster
Bacterium Cell Walls: Gram + and Gram – http://virtuallab.nmsu.edu/stain.php
Cell Walls cont’d Chemical nature of a cell wall can be determined by Gram Staining. By finding out what colour the cell produces when it is gram stained you can figure out the type of carbohydrates in the cell wall. Why would this be helpful?
Movement Flagellum ~ Tail like structure that whips around to propel the bacterium Cilia~ small hair-like projections surrounding the cell that help it to “swim”, moves back and forth in a synchronized movement Non motile ~ Sticky cilia like structures that keep the bacterium from moving
Flagella peri = around
Bacterial Respiration Aerobic Anaerobic Obligate Aerobes Obligate Anaerobes Facultative Anaerobes Grows in the presence of oxygen Grows in the absence of oxygen Must have oxygen Must have NO oxygen Can grow with or without oxygen
Bacteria and Metabolism Autotrophs Heterotrophs Chemotrophs
Autotrophs make their own energy use solar energy (or other chemical compounds) to ‘fix’ carbon dioxide eg. Cyanobacteria uses photosynthesis to make glucose
Example: Cyanobacteria Photosynthetic Bluish-greenish color Contain membranes that carry out p/s
Example: Cyanobacteria Do not contain the same type of chloroplasts as plants do This bluish-greenish algae can be found nearly everywhere on earth. Can survive in extremely hot and cold environments
Why are Cyanobacteria not in the Plant Kingdom?? • Can exist unicellularly • Prokaryotic (no nucleus and membrane-bound organelles)
Heterotrophs Obtain energy from eating other organisms Eg. E. coli
Chemotrophs makes own energy from chemicals like sulfur or hydrogen sulfide Eg. Archaebacteria living in deep sea vents
Other Archaea- Terms • Chemotrophs/Methanogens– convert chemical compounds into methane gas • Halophiles– like salt water (oceans) • Extreme Thermophiles– like warm environments (hot springs) • Psychrophiles– cold-loving organisms (Arctic soil)
Bacterial Reproduction Binary Fission Conjugation Spore Formation
1) 2) 3) Cellular organism copies its genetic information then splits into two identical daughter cells.
Conjugation Sexy time! 1 bacterial cell passes a copy of a plasmid through a hollow pilus For example, that contains the information such as a resistance to penicillin 1) 2) 3)
Spore Formation: Endospore A type of dormant cell (sometimes for years) Exhibit no signs of life Highly resistant structure that forms around the chromosome when cell is under some sort of environmental stress such as: -High temperatures -Irradiation -Strong acids -Disinfectants
Archaebacteria or Archaea Lack important carbohydrate found in cell walls (Gram -) Different lipids in their cell membrane Different types of ribosomes Very different gene sequences Do not cause disease Can live in extremely harsh environments Do not require oxygen (anaerobic)
Eubacteria Make up the larger of the two prokaryote kingdoms Generally are surrounded by a cell wall composed of complex carbohydrates Gram + and – Can cause disease Live nearly everywhere
MICROVIEWER ACTIVITY • make a chart similar to this one • use the microviewers provided to list examples of helpful bacteria and for each, why they are helpful • do the same for harmful bacteria • practice naming the type of shape and groupings
This powerpoint was modified by Mrs. S. Kerr, Mrs. S.Y. Chen-Allen and Mrs. N. Brannan from www.worldofteaching.com
Exit Card Draw what you think the following look like (refer to your notes): Streptobacilli Staphylococci