prokaryotes

Question 1

tree of life

Answer 1

bacteria, archaea, then eucarya branched off of archaea

Question 2

prokaryotes lack membrane bound nucleus and organelles but have a

Answer 2

cell wall

Question 3

cell wall contains

Answer 3

peptidoglycan

Question 4

function of cell wall

Answer 4

maintains shape, provides protection, prevents osmotic bursting

Question 5

2 types of cell walls

Answer 5

gram negative: thin peptidoglycan, lipopolysaccharide (endotoxin) and bilayered membrane, red

gram positive: thick peptidoglycan, single cell (plasma) membrane, purple

Question 6

cell membrane/ plasma membrane

Answer 6

infolds for respiration/ photosynthesis

Question 7

cell membrane function

Answer 7

selectively permeable; regulates movement in/out of cell
synthesis of cell wall components
assists w DNA replication
secretes proteins
contains flagella

Question 8

what is cell membrane composed of

Answer 8

phospholipid bilayer, carbohydrates and proteins

Question 9

capsule

Answer 9

coating of molecules external to the cell wall, made of sugars and/or proteins

Question 10

capsule function

Answer 10

adhesion to substrate, cohesion, biofilms, protection against host immune system, camouflage from WBCs

Question 11

centre of cell membrane is ____ and outer is ____

Answer 11

hydrophobic, hydrophilic

Question 12

pili and fimbriae

Answer 12

when they are short an abundant the function is adhesion
when they are long and sparse the function is conjugation (joins one bacterium to another)

Question 13

flagellum

Answer 13

allow bacteria to move, can rotate clockwise or anticlockwise, can be outside or inside the cell and when cell flexes moves in corkscrew motion

Question 14

nucleoid

Answer 14

bacterial chromosome, single ring of DNA (haploid)

Question 15

what exists in the cytoplasm

Answer 15

Ribosomal DNA

Question 16

DNA on plasmids

Answer 16

-small circles of DNA, not essential for survival but advantageous in stressful conditions

Question 17

bacillus shape

Answer 17

rods

Question 18

coccus shape

Answer 18

balls

Question 19

coccobacillus shape

Answer 19

ovals, somewhere inbetween coccus and bacillus

Question 20

spriochaete shape

Answer 20

squiggles

Question 21

endospores

Answer 21

large gram positive rods, thermostable and destroyed only by moist heat at 121 degrees for 15 mins, basis of sterilization standards

Question 22

why is mycoplasma an unusual bacteria

Answer 22

-lacks cell well
-smallest autonomous growing organism
-simple
-pleomorphic: resistant to lysis
-found on mucosal surfaces

Question 23

why is chlamydia an unusual bacteria

Answer 23

-energy parasite, stripped down genome, hijacks host metabolism

Question 24

rickettsia

Answer 24

bacteria, obligate intracellular parasites (requires a host to fulfil life cycle)
usually vector borne

Question 25

biofilms

Answer 25

mixed communities, embedded in a matrix, metabolic cooperation, resistance to removal

Question 26

ways biofilms communicate

Answer 26

homoserine lactones (quorum sensing) electrical signals genetic exchange

Question 27

two types of autotrophs

Answer 27

photoautotroph and chemoautotroph

Question 28

two types of heterotophs

Answer 28

photoheterotroph and chemoheterotroph

Question 29

photoautotroph energy source and carbon source

Answer 29

energy source: light carbon source: CO2

Question 30

chemoautotroph energy source and carbon source

Answer 30

inorganic chemicals, CO2

Question 31

photoheterotroph energy source and carbon source

Answer 31

light, organic compounds

Question 32

chemoheyerotroph energy source and carbon source

Answer 32

organic compounds, organic compounds

Question 33

obligate aerobes

Answer 33

require O2 for respiration, growth

Question 34

facultative anaerobes

Answer 34

-can survive with or without oxygen, prefer O2 but can ferment organic molecules for ATP

Question 35

obligate anaerobes

Answer 35

poisoned by oxygen, use inorganic molecules or fermentation (organic molecules)

Question 36

aerotolerant anaerobes

Answer 36

grow anaerobically, but don't die in presence of O2

Question 37

whats average generation time for prokaryotes (doubling time)

Answer 37

20 mins

Question 38

conjugation

Answer 38

plasmid gene transfer

Question 38

how do bacteria reproduce

Answer 38

asexual binary fission one cell splits into two daughter cells

Question 38

what are some ways genetic variation occurs in bacteria

Answer 38

mutation, transformation, conjugation and transduction

Question 39

transformation

Answer 39

take up foreign DNA from environment

Question 40

transduction

Answer 40

gene transfer between cells by viruses (phages)

Question 41

extremophiles:

Answer 41

thermophiles; high temp psychrophile; low temp acidophile; acid barophile; pressure xerophile; dry halophile; salt

Question 42

name some human applications

Answer 42

microbial leaching/ mining, fuel production, bioremediation, biotechnology

Question 43

first cellular life

Answer 43

cyanobacteria utilized atmospheric elements to produce O2 which allowed for greater diversity of life

Question 44

compare prokaryote cell wall to fungi's and plant cell's

Answer 44

prokaryote cell wall; peptidoglycan, gram pos or neg fungi cell wall; chitin plant cell wall; cellulose

Question 45

general cell structure from out to in

Answer 45

surface filaments (pili and fimbriae, flagellum) capsule cell wall plasma membrane genetic material in cytoplasm (nucleoid; bacterial chromosome single ring of DNA (haploid), ribsomal DNA in cytoplasm, DNA on plasmids (not essential for survival))