Chapter 3

Question 1

coccus bacteria shape

Answer 1

spherical or ball-shaped

Question 2

bacillus bacteria shape

Answer 2

rod, cylindrical

Question 3

vibrio bacteria shape

Answer 3

rods that are gently curved

Question 4

spirillum bacteria shape

Answer 4

slightly curled or spiral-shaped body (rigid helix)

Question 5

spirochete bacteria shape

Answer 5

corkscrew-shaped; spiral cell, more flexible (resembles a spring)

Question 6

filaments bacteria shape

Answer 6

produce multiple branches off of a basic rod

Question 7

what are staphylococci (micrococci)?

Answer 7

irregular clusters of cocci cells

Question 8

what are streptococci?

Answer 8

chains of cocci

Question 9

what are sarcina?

Answer 9

cubical packet of eight, sixteen, or more cocci cells

Question 10

what are streptobacilli?

Answer 10

chain of several bacilli

Question 11

what are palisades?

Answer 11

bacilli cells of a chain remain partially attached by a small hinge region at the ends

Question 12

spirilla definition

Answer 12

occasionally found in short chains

Question 13

spirochetes definition

Answer 13

rarely remain attached after cell division

Question 14

Monotrichous flagella

Answer 14

single flagellum

Question 15

Lophotrichous flagella

Answer 15

small bunches or tufts of flagella emerging from the same site

Question 16

Amphitrichous flagella

Answer 16

flagella at both poles of the cell

Question 17

Petrichous flagella arrangement

Answer 17

flagella are dispersed randomly over the surface of the cell

Question 18

What are the 2 types of chemotaxis (explain each)

Answer 18

positive chemotaxis: movement toward a favorable chemical stimulus

negative chemotaxis: movement away from a repellant

Question 19

role of fimbriae

Answer 19

• bristle-like fibers sprouting off the surface of many bacterial cells
• allow tight adhesion between fimbriae and epithelial cells, allowing bacteria to colonize and infect host tissues

Question 20

role of pili

Answer 20

-used in conjugation between bacterial cells (partial DNA transfer from one cell to another)

Question 21

what can Type IV pilus do?

Answer 21

it can transfer genetic material, act like fimbriae and assist in attachment, and act like flagella and make a bacterium motile

Question 22

what are nanotubes (nanowires)?

Answer 22

• thin, long, tubular extensions of the cytoplasmic membrane

- used as channels to transfer amino acids or to harvest energy by shuttling electrons to iron-rich substances

Question 23

what is the S layer in bacteria?

Answer 23

single layers of thousands of copies of a single protein linked together like tiny chain link fences (armour)

• only produced when bacteria are in a hostile environemnet

Question 24

what is glycocalyx role in bacteria?

Answer 24

coating of repeating polysaccharide or glycoprotein units

Question 25

what are the types of glycocalyx layer

Answer 25

slime layer: loose, protects against loss of water and nutrients capsule: more tightly bound, denser, and thicker; produce a sticky (mucoid) character to colonies on agar

Question 26

2 types of flagellar movement

Answer 26

run: rotation fo flagellum counterclockwise, resulting in a smooth linear direction tumble: reversal of the direction of the flagellum, causing the cell to stop and change course (clockwise)

Question 27

3 layers of the cell envelope

Answer 27

cell wall cytoplasmic (cell) membrane outer membrane

Question 28

What are Mycoplasmas

Answer 28

bacteria that naturally lack a cell wall; have sterols in the cell membrane that stabilize the cell against lysis

Question 29

What are L forms

Answer 29

bacteria that naturally have cell walls but lose it during part of their life cycle

Question 30

What disease does Bacillus anthracis cause?

Answer 30

anthrax

Question 31

What disease does Clostridium tetani cause?

Answer 31

tetanus

Question 32

What disease does Clostridium perfringens cause?

Answer 32

gas gangrene

Question 33

What disease does Clostridium botulinum cause?

Answer 33

botulism

Question 34

What disease does Clostridioides difficile cause?

Answer 34

a serious gastrointestinal disease