Microbiology Exam 1 Study Guide

LABORATORY

Agar – the substance that causes substance to remain solid

PDA Potato Dextrose Agar – “selective” for fungus (yeasts, molds)

Photosynthesis – takes in CO2, puts out O2

Protozoa – unicellular heterotrophic eukaryotes, lack cell wall, classified by motility

Algae – photosynthetic eukaryotes characterized by chloroplasts and absence of roots. Produce 75% of Earth’s O2 by photosynthesis

MSA plates contain a high amount of salt to select for STAPHYLOCCUCUS.

Mouth epithelial cells revealed most bacteria were coccus shaped and associated with our cells

Hemolysis- B (yellow, very revealed) A (green, somewhat revealed) Y (hard to see) our mouth had some A and a little Y

B completely destroy RBCs, A partially destroy the RBCs, Y does not destroy RBCs.

MSA plates are high in salt that select for staphylococcus

Pathogenic staphylococcus ferment mannitol plates to yellow due to acid production

Gram-stain – FIRST test performed to identify bacteria, goalis to have single, well-isolated colonies.

Gram-pos turn out violent, gram-neg turn pink AFTER safranin

Gram-pos have the peptidoglycan very vulnerable

Order of Gram-stain: Fixation, Crystal Violet, Iodine, Decolorization, Safranin

Molds are multicellular fungi. Starts with formation as SPORE forms. Branches out, branches called HYPHAE. Collectively called MYCELIUM. VEGETATIVE HYPHAE absorb nutrition from the environment.

TEMPERATURE ORGANISMS

Psychrophiles - -10 to 20C

Psychrotrophs – 0 to 30C

Mesophiles – 10 to 50 ( MOST COMMON)

Thermophiles – 40 to 70C

Hyperthermophiles – 65 to 110C

Many human pathogens grow at 37C.

Systemic exposure – full body exposure

LECTURE

Likelihood of infection - (Number of Microbes)(Virulence)/(Host Immunity)

Hooke saw the first microbe

Leeuwenhoek developed the microscope, saw “animalcules”

Pasteur founded pasteurization, immunology and vaccination, germ theory

Bacteria and Archaea were around 1 billion years before photosynthetic...