topic 10

Question 1

prokaryotes

Answer 1

abundant and diverse (14% of biomass), highly adaptable (extreme conditions),

Question 2

what is a prokaryote

Answer 2

archaea and bacteria, simple cell structure, generally small and unicellular, various shapes, lack a nucleus (free circular genome), lack membrane-bound organelles

Question 3

prokaryote cell surface adaptations

Answer 3

cell wall that provides structure and protection, contain peptidoglycan (bacteria) or structural polysacchariedes (archaea)

Question 4

gram staining

Answer 4

differentiates bacterial cell-wall composition: gram positide have thick peptidoglycan, gram-negative have outer lipopolysaccharide membranes

Question 5

prokaryote capsules

Answer 5

sticky layer of polysaccharides/proteins, help to stick to surfaces or eachother, protect against dessivation, help some pathenogenic bacteria invade immune system

Question 6

fimbriae

Answer 6

short, hair like structures to stick to surfaces

Question 7

pili

Answer 7

longer hairs that allow for the exchange of DNA

Question 8

endospores

Answer 8

metabollically inactive prokaryotes (dormant state) for when conditions are inhospitable

Question 9

motility

Answer 9

use of flagella to move around (at the end(s) of the cell)

Question 10

taxis

Answer 10

movement in response to stimulus

Question 11

structure of prokaryotes

Answer 11

simple internal structure without compartmentalization, small genomes with single circular chromosome

Question 12

plasmids

Answer 12

additional small circular DNA molecules, extra genes/greater versatility

Question 13

binary fission

Answer 13

method of reproduction, asexual reproduction that results in identical copies of the initial cell

Question 14

what contributes to genetic diversity of prokaryotes

Answer 14

rapid reproduction, mutations, genetic recombination

Question 15

genetic recmbination in prokaryotes

Answer 15

genetic material exchanged beteen cells, horizontal gene transfer, transformation, transduction, or conjugation

Question 16

horizontal gene transfer

Answer 16

genetic recombination between different species

Question 17

transformation - recombination

Answer 17

bacteria taking up and integrating dna from external environment (often fragments/plasmids from dead bacteria)

Question 18

transduction

Answer 18

transfer of DNA via bacteriophages

Question 19

conjugation

Answer 19

direct transfer of DNA via a pilus, only from donor to recipient (unidirectional), frequently transferring plasmids

Question 20

phototrophs

Answer 20

obtain energy from light

Question 21

chemotrophs

Answer 21

obtain energy from chemicals

Question 22

autotrophs

Answer 22

use inorganic molecules as carbon sources (producing organic compounds)

Question 23

heterotrophs

Answer 23

obtain carbon by consuming organic matter

Question 24

obligate aerobes

Answer 24

rely on o2 for cellular respiration

Question 25

obligate anaerobes

Answer 25

inhibited by o2, use fermentation/anaerobic respiration for energy

Question 26

faculative anaerobes

Answer 26

switch between using oxygen or not, depending on availability

Question 27

biological nitrogen fixation

Answer 27

prokaryotes converting atmospheric nitrogen into ammonia

Question 28

challenges to prokaryote phylogenies

Answer 28

horizontal gene transfer complicates lineages, archaea share characteristics with prokaryotes and eukaryotes

Question 29

proteobacteria

Answer 29

gram negative, alpha-epsilon

Question 30

alpha proteobacteria

Answer 30

associated with eukaryote hosts (rhizobium in legume roots), hypothesized to have evolved to eukaryotic mitochondria

Question 31

gamma and epsilon proteobacteria

Answer 31

pathogens (salmonella, e coli, h pylori)

Question 32

chlamydias

Answer 32

intracellular parasites that live within animal cells, rely on host, gram negative

Question 33

spirochetes

Answer 33

helical heterotrophs, some parasitic, moves efficiently through host tissues

Question 34

cyanobacteria

Answer 34

photoautotrophs that generate oxygen, eukaryotic chloroplasts hypothesized to have evolved, some toxic

Question 35

gram-positive bacteria

Answer 35

decomposers found in soil (actinomycetes -- antibiotics), can be pathenogenic (anthrax, botulism)

Question 36

archaea

Answer 36

simple prokaryotic cell organization with cell walls without peptidoglycan, often extremophiles

Question 37

methanogens

Answer 37

thrive in anoxic environments, produce methane as a waste metabolite

Question 38

extreme halophiles

Answer 38

archaea found in highly saline environments

Question 39

extreme themophiles

Answer 39

archaea found in ery hot environment, often chemoautotrophs

Question 40

prokaryote role in ecosystems

Answer 40

oxygen production, nitrogen fixation, chemical element cycling, chemoheterotrophic prokaryotes as decomposers

Question 41

symbiotic relationships

Answer 41

long term ecological relationships: mutualism, commensalism, parasitism (pathogens = disease causing)

Question 42

prokaryotes in industry

Answer 42

food production (dairy), decomposers used for bioremediation and sewage treatment, genetic engineering