Internal and External to the Cell Wall

Question 1

what are slime layers?

Answer 1

composed of diffuse, unorganized material that can be easily removed

Question 2

T/F slime layers are commonly found in medically relevant bacteria

Answer 2

F, in environmental bacteria

Question 3

What are slime capsules?

Answer 3

composed of rigid, well organized layers that are tight around the cell

Question 4

T/F slime capsules are commonly found in pathogenic bacteria

Answer 4

True

Question 5

What stain is utilized to see slime capsules under an electron microscope

Answer 5

India Ink

Question 6

What are three advantages for bacteria to have a slime capsule?

Answer 6

allows pathogenic organisms to hide from hosts immune system
allows bacteria to stick better to whatever surface theyre on
allows bacteria to be safe from dessication

Question 7

What are fimbtiae

Answer 7

short, fine, bristle-like appendages

Question 8

What is the function of fimbriae, up to how many can be on one bacteria

Answer 8

attachment mediators, make first contact with the environment, up to 1,000

Question 9

T/F fimbriae are only located on one pole

Answer 9

false surround entire perimeter

Question 10

What are pili

Answer 10

elongated, rigid tubular structures

Question 11

T/F, pili are always present

Answer 11

false, formed only when organisms are close and start communicating.

Question 12

what is the function of pili

Answer 12

exchange DNA

Question 13

What is the primary function of flagella

Answer 13

motility

Question 14

Flagella are (rigid/soft), and have a (hollow/dense) (linear/helical) structure

Answer 14

rigid, hollow, helical

Question 15

What kind of microscope is necessary to see flagella

Answer 15

electron microscope

Question 16

What is the monotrichous arrangement of flagella

Answer 16

singular flagellum on one singular pole

Question 17

What is the amphitrichous arrangement of flagella?

Answer 17

tufts of flagella from both ends of the cell

Question 18

what is the lophotrichous arrangement of flagella

Answer 18

tuft of flagella from one end

Question 19

what is the peritrichous arrangement of flagella

Answer 19

flagella all around the perimeter

Question 20

What are the three main components of flagella?

Answer 20

filament, hook, basal body

Question 21

what is the filament composed of?

Answer 21

composed of around 20,000 flagellin proteins and a cap with 5 varying proteins arranged in a hollow helical tube

Question 22

what is the function of the cap?

Answer 22

plays a role in attachment and filament assembly

Question 23

What is the function of the hook?

Answer 23

connects the filament to the basal body

Question 24

what is the basal body?

Answer 24

the motor of the flagellum

Question 25

what is the function of the basal body

Answer 25

contains rings that supply motor proteins with a proton gradient in order to allow movement

Question 26

How many rings are present in the basal body of gram - bacteria? what are they?

Answer 26

4, L ring, P ring, MS ring, C ring

Question 27

How many rings are present in the basal body of gram + bacteria? what are they?

Answer 27

2, Ms ring, C ringT

Question 28

T/F the flagellum grows from the base

Answer 28

false, grows from the tip

Question 29

What is the structure and fucntion of MS and C rings?

Answer 29

have a helical arrangement of charges on them, move protons across motor proteins, providing the force needed to start movement

Question 30

How many protons are necessary per revolution during flagellar movement?

Answer 30

1200 per revolution

Question 31

What role do chemoreceptors play in flagellar movement

Answer 31

signal to the fli proteins associated with the MS and C rings to stop when bacteria are entering an unsuitable environment

Question 32

How do peritrichous bacteria move?

Answer 32

to dart forward, flagella are bundled and rotated in a counter clockwise direction
when stopped by chemoreceptors , they tumble by pushing the flagella out in a clockwise rotation

Question 33

How do polar bacteria move?

Answer 33

in bacteria with reversible flagella, counterclockwise to go forwards, clockwise to go backwards
in bacteria with a unidirectional flagella, clockwise to run forward, stop to turn - can only go forward

Question 34

what is brownian movement?

Answer 34

movement in fluid

Question 35

What are some features of archael flagella?

Answer 35

thin
filament not comprised of flagellin
dense, filled structure
Use ATp hydrolysis for energy

Question 36

What is the structure of the basal body in archaea

Answer 36

comprised of around 12 proteins

Question 37

How many different proteins is the archael filament comprised of?

Answer 37

7-12 different proteins