Lecture 2: The Prokaryotes (Bacteria & Archaea)

Question 1

most life on the planet are

Answer 1

unicellular prokaryotes

Question 2

Characteristics of bacteria and archaea

Answer 2

1. microscopic
2. tremendous numbers
3. thrive almost everywhere
4. mostly unicellular

Question 3

shapes of prokaryotic cells

Answer 3

1. spheres (cocci) like streptococcus
2. rods (bacilli) like e. coli
3. spirals like syphilis

Question 4

Bacteria have cell walls with

Answer 4

peptidoglycan

Question 5

peptidoglycan

Answer 5

network of sugar polymers cross-linked by polypeptides

Question 6

Archaea contain polysaccharides and protein but lack

Answer 6

peptidoglycan

Question 7

eukaryote cell walls are made of

Answer 7

cellulose or chitin

Question 8

antibiotics target _____ and damage bacterial cell walls

Answer 8

peptidoglycan

Question 9

Prokaryotes also lack

Answer 9

nuclei and other organelles

Question 10

frimbriae:

Answer 10

hairlike appendages that help cells adhere to other cells or substrate

Question 11

Capsule

Answer 11

sticky layer of polysaccharide that can help cell adherence and/or evade host immune system

Question 12

sex pilus

Answer 12

facilitates conjugation

Question 13

flagella

Answer 13

helps bacteria move through

Question 14

prokaryote chromosomes are

Answer 14

circular and not in a nucleus

Question 15

bacteria exhibit taxis, which is

Answer 15

the ability to move toward or away from certain stimuli
(toward = + , away = - )

Question 16

basal apparatus

Answer 16

motor; system of rings in cell wall and membrane powered by ATP pump

Question 17

how do prokaryotes reproduce

Answer 17

binary fission

Question 18

prokaryotes divide how often?

Answer 18

every 1-3 hours

Question 19

though mutation rates are slow, prokaryotes accumulate rapidly which leads to

Answer 19

rapid evolution

Question 20

3 factors of prokaryote diversity

Answer 20

1. Rapid reproduction
2. Mutation
3. Genetic recombination

Question 21

prokaryotic DNA is brought together by

Answer 21

transformation, transduction, and conjugation

Question 22

transformation

Answer 22

incorporating foreign DNA from the surrounding environment

Question 23

conjugation

Answer 23

plasmids are transferred between two bacterial cells that are temporarily joined

Question 24

transduction

Answer 24

movement of genes between bacteria by bacteriophages

Question 25

transduction steps

Answer 25

land on target, pierce through, then insert DNA

Question 26

phototrophs

Answer 26

obtain energy from light

Question 27

chemotrophs

Answer 27

obtain energy from chemicals

Question 28

autotrophs

Answer 28

require CO2 as a carbon source

Question 29

Heterotrophs

Answer 29

require organic nutrient as carbon source

Question 30

photoautotroph

Answer 30

use energy from light (ex: plants)

Question 31

chemoautotroph

Answer 31

energy from redox of inorganic compounds (ex: sulphur)

Question 32

photoheterotroph

Answer 32

derive carbon requirements from organic compounds

Question 33

chemoheterotroph

Answer 33

consumes other organisms for energy (ex: humans )

Question 34

heterocytes

Answer 34

nitrogen-fixing cells that exchange metabolic products in Anabaena

Question 35

biofilms

Answer 35

surface-coating colonies with various functions such as

Question 36

Role of prokaryotes

Answer 36

recycling chemical elements, chemoheterotrophic decomposers, nitrogen-fixing prokaryotes

Question 37

Symbiosis

Answer 37

ecological, close-contact relationship with a larger host and a smaller symbiont

Question 38

mutualism

Answer 38

both symbiotic organisms benefit

Question 39

commensalism

Answer 39

one organism benefits while neither harming nor helping the other

Question 40

parasitism

Answer 40

parasite harms but doesn't kill its host

Question 41

parasites that cause disease are called

Answer 41

pathogens

Question 42

important pathogenic prokaryotes

Answer 42

exotoxins and endotoxins

Question 43

exotoxins

Answer 43

cause disease even if prokaryotes that produce them are not present (always there even if organism is dead)

Question 44

endotoxins

Answer 44

released only when bacteria die and cell walls break down

Question 45

other prokaryote functions

Answer 45

animal digestive functioning, bioremediation, producing ethanol