chapters 1-4: intro to microbio & chemical properties

Question 1

microorganisms

Answer 1

(aka microbes) organisms too small to be see with the unaided eye

Question 2

pathogen

Answer 2

disease producing organism

Question 3

what is a prokaryote?

Answer 3

an organism without a membrane bound nucleus; “prenucleus”

Question 4

characteristics of bacteria

Answer 4

prokaryote, single-celled, peptidoglycan cell walls, divide via binary fission; may swim by using appendages (flagella)

Question 5

characteristics of archaea

Answer 5

prokaryote, lack peptidoglycan cell walls (may lack cell wall entirely), often live in extreme environments, generally not known to cause disease in humans
Ex) methanogens, extreme halophiles, extreme thermophiles

Question 6

what is a eukaryote?

Answer 6

an organism with a membrane bound nucleus

Question 7

characteristics of fungi

Answer 7

eukaryote, chitin cell walls, absorb organic chemicals for energy
Ex) yeasts - unicellular
molds (mycelia & hyphae) & mushrooms - multicellular

Question 8

characteristics of protozoa

Answer 8

eukaryote, absorb or ingest organic chemicals, may be motile via pseudopods, cilia, or flagella, free living or parasitic, reproduce sexually or asexually

Question 9

characteristics of viruses

Answer 9

acellular, consist of DNA or RNA core, core is surrounded by protein coat; are replicated only when they are in a living host cell

Question 10

who reported that “living things are composed of little boxes / ‘cork cells’”?

Answer 10

Robert Hooke

Question 11

cell theory

Answer 11

all living things are composed of cells

Question 12

who discovered first microbes as “animalcules” (microscopic animals)

Answer 12

Anton van Leeuwenhoek

Question 13

spontaneous generation

Answer 13

hypothesis that life arises from nonliving matter; a “vital force” is necessary for life

Question 14

biogenesis

Answer 14

[Rudolf Virchow] hypothesis that living cells arise only from preexisting cells

Question 15

germ theory of disease

Answer 15

uses Koch’s postulates (experimental steps) to demonstrate that a specific microbe causes a specific disease

Question 16

miasma theory of disease

Answer 16

obsolete theory that diseases (cholera, black death) come from a noxious form of “bad air” or from rotting organic matter

Question 17

significance of Redi’s “jar of meats” experiment

Answer 17

debate over spontaneous generation; covered jars and sealed jars did not get maggots while opened jars did

Question 18

significance of Pasteur’s “long necked flasks” experiment

Answer 18

disproved spontaneous generation by using s-shaped flasks to keep microbes out but let air in; when the broth was not sealed, there was microbial growth; when the broth was sealed, there was no microbial growth; shows that microbes originate in air or fluids

Question 19

Koch’s postulates

Answer 19

1) microorganism must be observed in every case of the disease
2) it must be isolated and grown in pure culture
3) the pure culture, when inoculated in an animal, must reproduce the disease
4) microorganism must be recovered from diseased animal

Question 20

“magic bullet” and who discovered it

Answer 20

[Paul Ehrlich] synthetic drug that could destroy a pathogen without harming the host;
- synthetic arsenic drug to treat syphilis = salvarsan

Question 21

who inoculated a person with cowpox virus in 1796 (beginning of vaccinations)?

Answer 21

Edward Jenner

Question 22

who created the first antibiotic, penicillin on accident by the Penicillium fungus?

Answer 22

Alexander Fleming

Question 23

taxonomy

Answer 23

[Linnaeus] classification of organisms by scientific nomenclature (genus and specific epithet); italicized and genus is capitalized

Question 24

protons

Answer 24

subatomic particle with positive charge; makes up nucleus of atom

Question 25

neutrons

Answer 25

subatomic particle with no electrical charge; makes up nucleus of atom

Question 26

electrons

Answer 26

subatomic particle with negative charge

Question 27

chemical reaction

Answer 27

involves the making or breaking of bonds between atoms

Question 28

endergonic reactions

Answer 28

absorbs energy

Question 29

exergonic reactions

Answer 29

releases energy

Question 30

element

Answer 30

pure element which cannot be broken down by chemical means

Question 31

isotope

Answer 31

variants of a chemical element which differ in neutron numbers

Question 32

valence

Answer 32

the number of missing or extra electrons in the outermost shell

Question 33

ionic bond

Answer 33

attractions between ions of opposite charge; one atom loses electrons and one atom gains electrons

Question 34

ions

Answer 34

charged atoms that have gained or lost electrons

Question 35

covalent bond

Answer 35

two atoms share one or more pairs of electrons

Question 36

polar

Answer 36

unequal distribution of electrons; “pull”

Question 37

nonpolar

Answer 37

equal distribution of electrons; “no pull”

Question 38

properties of water

Answer 38

• temperature buffer (absorbs heat)

- great solvent: polar substances undergo dissociation in water, forming solutes

Question 39

solute

Answer 39

a substance dissolved in another substance

Question 40

solvent

Answer 40

substance that dissolves a solute

Question 41

acid

Answer 41

substances that dissociate into one or more hydrogen atoms and one or more negative ions

Question 42

base

Answer 42

substances that dissociate into one or more hydroxide ions and one or more positive ions

Question 43

pH

Answer 43

concentration of H+ in a solution