Bacterial Structure 2&3. 4

Question 1

Swarming locomotion

Answer 1

is the multicellular movement of bacteria across a surface and is powered by rotating helical flagella

Question 2

Swimming locomotion

Answer 2

is the movement of individual bacteria in liquid, also powered by rotating flagella

Question 3

Twitching locomotion

Answer 3

is surface movement of bacteria that is powered by the extension of pili, which then attach to the surface and subsequently retract, pulling the cell closer to the site of attachment.

Question 4

Gliding locomotion

Answer 4

is active surface movement that does not require flagella or pili and involves focal adhesion complexes.

Question 5

Sliding locomotion

Answer 5

is passive surface translocation that is powered by growth and facilitated by a surfactant

Question 6

Motility in most microorganisms is

accomplished by?

Answer 6

flagella

Question 7

flagella are

Answer 7

complex structures of several proteins, most of which anchor into cell wall and cytoplasmic membrane

Question 8

**What drives the flagellar motor rotational movement?

Answer 8

PMF= protein motive force

•About 1000 protons are used up per rotation

Question 9

*flagellin is a powerful stimulant of the host ___ immune response

Answer 9

innate

Question 10

flagella has a speed of about ____ cell lengths/s and rotates at speeds up to ______ revolutions per second?

Answer 10

60 cell lengths/ second

300 revolutions per second

Question 11

In pathogens flagella are often??

Answer 11

virulence factors (add in degree of damage or evasiveness to host)

Question 12

Counterclockwise rotation moves the cell in a direction called a?

Answer 12

run

Question 13

Clockwise rotation causes the tuft of flagella to spread, resulting in?

Answer 13

tumbling of the cell

Question 14

In the processes of chemotaxis and phototaxis, random movement of a
prokaryotic cell can be biased either

Answer 14

toward or away from a stimulus by controlling the degree to which runs or tumbles occur

Question 15

How can motile bacteria respond to chemical and physical gradients in their environment?

Answer 15

chemotaxis or phototaxis

*controlled by a network of cell associated sensory and response proteins that controls runs/tumbles

Question 16

Positive chemotaxis

Answer 16

occurs toward an attractant when the sum of bacterial runs, or movement from flagella rotation, results in net movement in the direction of increasingconcentration of a chemical

Question 17

Negative chemotaxis

Answer 17

occurs when motile Bacteria move away from a repellant

Question 18

what is the source ofH-antigen?

Answer 18

filament of flagella

Question 19

What does H-antigen do?

Answer 19

induces antibodies of our immune system

*if you have anti-H-antigen antibodies you may have been infected with that bacterium

Question 20

monotrichous

Answer 20

single flagellum

Question 21

amphitrichous

Answer 21

bipolar flagella

Question 22

lophotrichous

Answer 22

tufted flagella

Question 23

peritrichous

Answer 23

flagella that surround the perimeter