BIOS 242 final Chamberlain

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BIOS 242 final Chamberlain

• 4 important facts about Antoni van Leeuwenhoek (Dutch)

–Answer -First person to see protozoa and bacteria -Began making and using simple microscopes -Often made a new microscope for each specimen -Examined water and visualized tiny animals, fungi, algae, and single-celled proto- zoa; "animalcules

• 2 important facts about Carolus Linnaeus

–Answer -developed taxonomic system for naming plants and animals and grouping similar organisms together -Leeuwenhoek's microorganisms grouped into six categories as follows –Answer æFungi æProtozoa æAlgae æBacteria æArchaea æSmall multicellular animals

• Describe 2 important contributions of Pasteur

–Answer -Developed germ theory of disease -His experiment –Answer

æSwan neck flasks were used –Answer

–Answer allowed for airflow without allowing the introduction of environmental microbes æWhen the "swan-necked" flasks remained upright, no microbial growth appeared æWhen the flask was tilted, dust from the bend in the neck seeped back into the flask and made the infusion 1 / 4

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cloudy with microbes within a day

• What are prokaryotes, and what are the characteristics of them?

–Answer -Archaea and bacteria.-Characteristics –Answer no membrane surrounding DNA, no nucleus, no membrane bound organelles, smaller than eukaryotes

• What are eukaryotes, and what are the characteristics of them?

–Answer -algae, protozoa, fungi, microanimals -Acellular Infectious Agents –Answer viruses, viroids, prions.-Characteritics –Answer have membrane surrounding DNA, have nucleus, have membrane bound organelles, larger than prokaryotes

• What are archaea & bacteria, and what are the characteristics of them?

–Answer

• Unicellular, lack nuclei, smaller than eukaryotes, ubiquitous (everywhere), asexual

-bacteria cell walls contain peptidoglycan -archaea cell walls composed of polymers, NOT peptidoglycan

• What is fungi, and what are the characteristics?

–Answer -Eukaryotic, obtain food from other organisms, has cell wall, plays role in fermentation -Mold –Answer multicellular, long filaments called hyphae, sexual & asexual 2 / 4

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-Yeast –Answer unicellular, asexual by budding, creates bread wine & beer through fermen- tation

• explain fermentation

–Answer happens in absence of oxygen. Creates cheese, yogurt, wine, beer, bread (yeast makes alcohol, bacteria make acid)

• what is protozoa and what are the characteristics?

–Answer Single-celled motile eu- karyotes, mostly asexual, sometimes sexual (involved in

MOVEMENT)

-Pseudopodia –Answer cell extensions that flow in direction of travel -Cilia –Answer numerous short protrusions that propel organisms, only in eukaryotes, com- posed of tubulin in eukaryotes -Flagella –Answer few, longer extensions than cilia, composed of tubulin in eukaryotes -Flagella and cilia respond to stimuli (taxis)

• what is algae, and what are the characteristics of it?

–Answer Unicellular or multicel- lular, photosynthetic, source of food for aquatic plants and animals, used to make agar which is used as a solidifying agent in microbial growth media. Example –Answer kelp, seaweed 3 / 4

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• what is serology?

–Answer The study of blood serum, especially with regard to the response of the immune system (antibody production) to pathogens or introduced substances

• what is Immunology?

–Answer The study of the body's defense against specific pathogens Etiology –Answer the cause of a disease

• what are the characteristics of gram positive staining results?

–Answer results in purple color, thick peptidoglycan cell wall, contains teichoic acid, retains crystal violet dye which gives it its purple color, must be stained by acid-fast bacteria which contains up to 60% mycolic acid

• what are the characteristics of gram negative staining results?

–Answer results in pink color, thin peptidoglycan cell wall, may contain LPS (lipopoly saccharide) which is an endotoxin, has periplasmic space between inner and outer membrane

• Explain the gram staining procedure.

–Answer

• Stain with crystal violet for 1 min, wash off- both gram pos. and gram neg. will appear purple
• Apply grams iodine for 1 min, wash off- iodine increases size of cells, both gram pos. and

gram neg. will remain purple

• Add 95% alcohol (acetone) drop by drop until alcohol runs clear, wash off- In gram neg. thin

peptidoglycan cell wall comes off and gram pos. (thick peptidoglycan cell wall) stays and remains purple.

• Counterstain with safranin for 45 sec., wash off, blot dry- safranin is used to stain the

colorless gram-negative bacteria making it appear pink.

• what are Glycocalyces?

–Answer Flagella, cilia, Fimbriae, pili & hami

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