Bacteria Cell Structure- Test 1

Question 1

What is the average size of bacteria?

Answer 1

0.2-2.0um diameter x 2 to 8um length

Question 2

There is great variety in bacteria but typically described by one of three basic shapes. What are those shapes?

Answer 2

-coccus- spherical
-bacillus- rod
-coccobacillus- short, plump
-vibrio- gently curved
-spirillum- helical, twisted rod
-spirochete- spring-like

Question 3

What does the arrangement of cells depend on?

Answer 3

the pattern of division and if/how cells remain attached after division

Question 4

rigid polysaccharide layer that provides strength

Answer 4

peptidoglycan

Question 5

Do gram-positives and gram-negative cells have different cell wall structures?

Answer 5

yes

Question 6

A gram-stain reaction determined by the cell wall thickness does not always what?

Answer 6

correlate with envelope structures

Question 7

Does a gram-positive or -negative cell have a inner and outer membrane?

Answer 7

negative

Question 8

How does Archaeal cell walls differ from bacterial?

Answer 8

-they lack peptidoglycan
-typically lack an outer membrane
-most lack polysaccharide wall and instead have s-layer (protein shell)

Question 9

What is the structure of bacterial lipopolysaccharide?

Answer 9

-they have ionic bonds to divalent cations and add strength
-the LPS replaces most of phospholipids in outer half of outer membrane
-Braun lipoprotein anchors outer membrane to peptidoglycan
-has a toxic component called endotoxin

Question 10

What are the major events in endospore formation?

Answer 10

starts at the vegetative cell cycle then goes through asymmetric cell division where you have the forespore and the mother cell then you go through engulfment where the mother cell engulfs the forespore and the outer spore membrane is formed then the late sporulation them maturation then the mother cell disappears and there is a free endospore and goes through germination and back into the vegetative cycle

Question 11

What are the different types of bacterial endospores?

Answer 11

terminal, subterminal, and central endospores

Question 12

coating of molecules external to the cell wall, made of sugars and/or proteins and have two types, slime layer and capsule

Answer 12

Glycocalyx

Question 13

What are the functions of glycocalyx?

Answer 13

-protect cells from dehydration and nutrient loss
-inhibit killing by white blood cells by phagocytosis contributing to pathogenicity
-attachment- formation of biofilms

Question 14

observed in many photosynthetic bacteria, observed in many bacteria with high respiratory activity

Answer 14

plasma membrane infoldings

Question 15

membrane bound organelle- site of anaerobic ammonia oxidation

Answer 15

anammoxosome in plantomycetes

Question 16

-functions as energy reserves, carbon or phosphorus reservoirs and/or have special functions
-enclosed by thin protein membrane
-reduces osmotic stress

Answer 16

storage inclusions

Question 17

smaller than eukaryotic ribosomes (prokaryotic 70s, eukaryotic 80s)

Answer 17

bacteria ribosomes

Question 18

transfer DNA from one cell to another

Answer 18

conjugative plasmids

Question 19

carry antibiotic resistance genes

Answer 19

R plasmids

Question 20

produce bacteriocins substances that destroy closely related species

Answer 20

col plasmids

Question 21

carry virulence genes

Answer 21

virulence plasmids

Question 22

carry genes for enzymes

Answer 22

metabolic plasmids

Question 23

-extrachromosomal DNA found in bacteria, archaea, some fungi; usually small, closed circular DNA molecules
-exist and replicate independently of chromosome; inherited during cell division
-classification via mode of existence, spread, and function

Answer 23

plasmids

Question 24

-hair-like appendages that allow for attachment

Answer 24

fimbriae

Question 25

-involved in motility -conjugation pili involved in DNA transfer from one cell to another

Answer 25

pili

Question 26

Archaea has what instead of pili?

Answer 26

Hami, also used for attachment, have hooks to help attachment

Question 27

-long thin appendages anchored in cell at one end -different arrangements -increase or decrease rotational speed relative to strength of proton motive force

Answer 27

bacterial flagella

Question 28

counterclockwise

Answer 28

run

Question 29

What is the difference of archaella from bacterial flagella?

Answer 29

smaller, proteins are unrelated and more similar to pili, move by rotation driven by ATP, generally swim much slower

Question 30

What is flagella powered by?

Answer 30

PMF

Question 31

movement typically occurs away from colony

Answer 31

surface motility

Question 32

requires type IV pili

Answer 32

twitching motility

Question 33

smooth, continuous motion along long axis without external structures, sometimes has a slime layer

Answer 33

gliding motility

Question 34

response of ionic strength

Answer 34

osmotaxis

Question 35

response to water

Answer 35

hydrotaxis

Question 36

response to oxygen

Answer 36

aerotaxis

Question 37

response to light

Answer 37

phototaxis