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Flashcards in Exam 1 Deck (32)
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1

Ergotism

Cause: mold Claviceps purpurea - produces toxic alkaloids
Symptoms: spasms, itching, mania, psychosis
Proposed explanation for bewitchment

2

Van Helmont

recognized that fermentation gave rise to gas and alchohol

3

Van Leeuwenhoek

invented simple microscope

4

Kirchner

Monk
first to claim to see "invisible worms" with microscope

5

Pasteur

researched heat preservation methods
described microbio of lactic acid fermentation
coined aerobic and anaerobic by investigation alch production of yeast
ended debate on spontaneous generation (via swan neck flask exp.)
used attenuated (less virulent) strain as vaccine for chicken cholera
injected Joseph Meister with "aged" spinal cord containing rabies virus

6

Koch

-worked with anthrax, wrote paper pointing to a bacterium as the cause of this disease = validation of germ theory of disease (some diseases are caused by microorgs)

-pure culture studies made possible (potato slices)

-discovered cause of TB and cholera

-Koch's postulates

7

Koch's postulates

1. microorg must be found in abundance in all orgs with disease and not in healthy orgs
2. microorg must be isolated from diseased org and grown in pure culture
3. culture should cause disease when put into healthy org
4. microorg must be reisolated from infected person and identified as identical to original

8

Walter Hesse

Koch's associate
First to use agar to isolate pure culture
Actually was his wife who suggested agar

9

Lister

Observed that people survived surgery but died of "ward fever"
Proposed that microbes in air and on doc's hand caused post-op infections
introduced thorough cleaning of wound then covering with phenol-saturated cloth
Machine that pumped mist of phenol was used during operations
lactic acid fermentation (showed that a specific bacterium caused the lactic acid fermentation in milk)

10

Ehrlich

Proposes that antibodies contribute to immunity
Shows that they are produced against the plant toxins ricin and abrin

11

Metchnikoff

discovered macrophages
work with phagocytosis

12

Twort

discovered bacteriophage (viruses that affect bacteria) accidentally when he noticed that some bacteria on plates became transparent

13

Transduction

When a bacteriophage inserts a virus into a host, it takes some of the host DNA with it which then is inserted into the next host

14

Griffith

discovers transformation (genetic alteration via uptake of foreign DNA through cell membrane) in bacteria and est. foundation for molecular genetics
Experiment w/ rats

15

Fleming

Publishes first paper describing penicillin and its effects on gram positive bacteria

16

Howard Florey & Ernest Chain

Produce extract of penicillin, isolated from Fleming's culture - show that it can cure infections in animals

17

Lederberg & Tatum

Describe conjugation in bacteria

18

Transformation

Genetic alteration via uptake of foreign DNA through cell membrane

19

Conjugation

Transfer of genetic material (plasmid) between cells by direct cell to cell contact

20

Crick, Wilkins & Watson

Double helix structure of DNA based on x-ray crystallography done by Rosalind Franklin

21

Rosalind Franklin

Did x-ray cyrstallography of DNA that lead to the description of the double helix structure by Crick, Wilkins and Watson

22

Gilbert & Sanger

Develop methods to sequence DNA

23

Prusiner

Finds evidence that class of infections proteins called prions cause scrapie

24

Prions

Protein molecules
Not infection, conversion: find prion like orgs in host and convert them to the bad form
Infectious agent composed of protein in a misfolded form

25

Mullis

Uses the heat stable enzyme from Thermus aquaticus to establish PCR technology

26

PCR

Polymerase chain reaction
Amplifies a piece of DNA

27

Acetic acid

pKa 4.75
inhibits gram positive and negative
yeasts and molds tolerant
Jellies

28

benzoic acid

pKa 4.19
pH range 2.5-4.5
inhibits yeasts and molds and enzymes
first antimicrobial premitted in foods
jellies

29

parabens

esterification of benzoic acid
pH 3-8
active against yeasts and molds, some bacteria (g+)
targets cytoplasmic membrane
jams

30

sorbic acid/sorbates

pKa 4.75
inhibits yeasts, molds, some bacteria
prevents germination of spores of clostridium botulinum
Jam