Chapter 1

• –Began making and using simple microscopes
• –Examined water and visualized tiny animals, fungi, algae, and single-celled protozoa; “animalcules”
• First to see bacteria

Developed taxonomic system for naming plants and animals

• fungi
• protozoa
• algea
• bacteria
• archea
• small multicellular animals

• yeasts and molds
• saccharomyces cervisiae: bakers yeast
• rizopus: bread mold,
• penecillium, 
• Aspergillus: pathogen

• animalia
• worm
• trichinosis

• protista
• african sleeping sickness 

algea

bakers yeast

• single celled
• similiar to animals in nutrient needs and cellular structure
• live freely in water or in animal hosts
• mostly asexual
• most are locomotive (pseudopodia, cilia, flagella)
•  Trypanosoma african sleeping sickness

• –Unicellular or multicellular
• can be spyrogyra or mixed diatoms 
• –Photosynthetic
• –Simple reproductive structures
• –Categorized on the basis of pigmentation, storage products, and composition of cell wall

• –Unicellular and lack nuclei
• –Much smaller than eukaryotes
• –Found everywhere there is sufficient moisture; some isolated from extreme environments
• –Reproduce asexually
• –Two kinds
• –Bacteria  – cell walls contain peptidoglycan(amino acids); some lack cell walls
• –Archaea – cell walls composed of polymers other than peptidoglycan, like glyco: sugar

• spontaneous regeneration yes or no
• what causes fermentation
• what causes disease
• how prevent infection and disease

• Aristotle proposed spontaneous regeneration  
• Redi: disproved macro spontaneous regeneration
• Needville: reproved spon. regen. by boiling beef broth and sealing with a cork. 
• Spallanzani: proved needham failed to boil long enough and or did not seal properly.  Microorganisms exist in air.  sealed his containers but folks argued that he did not allow enough air for microbes to thrive
• Pasteur: proved no s.r. by using the s-shaped necks  

–Scientists did not believe animals could arise spontaneously, but did believe microbes could

–Needham’s experiments with beef gravy and infusions of plant material reinforced this idea

• –Concluded that
• –Needham failed to heat vials sufficiently to kill all microbes or had not sealed vials tightly enough
• –Microorganisms exist in air and can contaminate experiments
• –Spontaneous generation of microorganisms does not occur
• –Critics said sealed vials did not allow enough air for organisms to survive and that prolonged heating destroyed “life force”

–When the “swan-necked” flasks remained upright, no microbial growth appeared

–When the flask was tilted, dust from the bend in the neck seeped back into the flask and made the infusion cloudy with microbes within a day

• -not spontaneous
• -not caused by air
• -bacteria causes acids (vinegar fermentation)
• -yeaste causes alcohol (fermentation)

• cheese
• alcoholic beverages
• soy sauce
• vinegar
• yoguart
• sour cream
• artificial sweetener
• bread

• Pasteur developed germ theory of disease
• Robert Koch studied causative agents of disease
•     –Anthrax
•     –Examined colonies of microorganisms

• Proved that specific pathogen caused a specific disease
•   –Simple staining techniques
• –First photomicrograph of bacteria
• –First photomicrograph of bacteria in diseased tissue
• –Techniques for estimating CFU/ml
• –Use of steam to sterilize media
• –Use of Petri dishes
• –Techniques to transfer bacteria
• –Bacteria as distinct species

• pathos : disease
• genein: to produce

study of cuasation of disease

pasteur discovered that bactera spoiled the wine led to the theory that diseases were caused by germs

• –Suspected causative agent must be found in every case of the disease and be absent from healthy hosts
• –Agent must be isolated and grown outside the host
• –When agent is introduced into a healthy, susceptible host, the host must get the disease
• –Same agent must be found in the diseased experimental host

study occurence, distribution and spread of disease

• –Semmelweis and handwashing
• –Lister’s antiseptic technique
• –Nightingale and nursing
• –Snow – infection control and epidemiology linked cholera to poisened water source
• –Jenner’s cow pox vaccine – field of immunology
• –Ehrlich’s “magic bullets” – field of chemotherapy: destroy the pathogen while remaining nontoxic to humans