Microbio Test 2

Question 1

Glycogen

Answer 1

Polymer of glucose

Question 2

Polyphosphate

Answer 2

A storage unit that saves phosphate for a bacteria.

Question 3

Carbon storage polymers

Answer 3

-PHB
-PHA
Glycogen

Question 4

Nutrient storage units of bacteria

Answer 4

-Carbon storage polymers
-Polyphosphate
-Elemental Sulfur

Question 5

Structures that control location of bacteria

Answer 5

-Magnetosomes
-Gas vesicles

Question 6

Magnetosomes

Answer 6

Help move the bacteria along the magnetic poles.

Question 7

Gas vesicles

Answer 7

Provides buoyancy for phototrophs

Question 8

Endospores

Answer 8

-Resistant to heat, harsh chemicals, and radiation
-Enable the survival during unfavorable conditions
-Dormant stage of life, no metabolic activity
-Mostly in Gram (+)

Question 9

Anatomy of a endospore

Answer 9

-Exosporium
-Spore coat
-Core wall
-Cortex
-DNA

Question 10

S-layers

Answer 10

-Paracrystalline
-Can be a cell wall and extra layer for Archaea
-Only can be extra layer for bacteria

Question 11

Glycocalyx

Answer 11

-Made of polysaccharides
-Capsule is tightly adherent
-Slime layer is loosely adherent

Question 12

Three functions of glycocalyx

Answer 12

-Adhesion to a surface or other cells
-> BIOFILM
-Prevent dissociation
-Avoid phagocytosis

Question 13

Cell surface apendages

Answer 13

-Protein structures
-Fimbriae
-Pili
Flagella

Question 14

Fimbriae

Answer 14

-Abundant
-Shorter
-Role in adherence

Question 15

Pili

Answer 15

-Fewer per cell
-Longer
-Retractable
-Type 4 -> Motility
-Adherence
-Conjugation (exchange of DNA) horizontal gene transfer

Question 16

3 parts of flagella

Answer 16

-Basal body
-Hook
-Filament

Question 17

Flagella synthesis

Answer 17

-Grows at the tip
-Many gene products involved

Question 18

Flagella arrangements

Answer 18

-Peritrichous (everywhere)
-Polar (one out the end)
-lophotrichous (multiple out of the end)
-Amphitrichous (multiple out of both ends)

Question 19

Archaella (Archaea’s form of flagella)

Answer 19

-Grows from the base like pili
-Energy source is ATP

Question 20

Bacterial gliding motility

Answer 20

-surface motility
-no obvious cell surface appendages
-caterpillar tractor
-Slime extrusion

Question 21

Chemotaxis

Answer 21

Moves in response to chemical signals

Question 22

Random walk

Answer 22

Swims and tumbles during swimming motility (not efficient)

Question 23

Biased random walk

Answer 23

Swims for a longer time in the correct direction and then tumbles (more efficient)

Question 24

Phototaxis

Answer 24

Movement towards light

Question 25

Aerotaxis

Answer 25

Movement towards oxygen

Question 26

Osmotaxis

Answer 26

Ionic strength

Question 27

Hydrotaxis

Answer 27

Movement towards water

Question 28

Binary Fission

Answer 28

Symmetric cell division in bacteria and archaea

Question 29

Petroff-Hausser Counting Chamber

Answer 29

Pros:
-Very fast
Cons:
-Can’t distinguish live vs. dead cells
-Viewing motile cells is hard
-Doesn’t work at low cell densities
-Need a microscope
-liquid culture

Question 29

Serial Dilutions

Answer 29

Pros:
-Counting live
-Will work with a high number of cells
Cons:
-Slow cells have to grow
-Cell clump
- “Great plate anomaly”

Question 29

Viable Count
(Plate cells, agar-based medium)

Answer 29

Spread plate method;
-Grown on agar
Pour plate method:
-Mixed with agar

Question 30

Spectrophotometer

Answer 30

Pros:
-Fast
-Observe growth phases
Cons:
-Can’t tell live vs. dead
-Doesn’t work well at high cell density

Question 31

Growth Phases in BATCH Cultures

Answer 31

-Lag
-Exponential
-Stationary
-Death

Question 32

Define or minimal medium

Answer 32

-All components are precisely known
****

Question 33

Psychrophile

Answer 33

-Cold Adaptations
-Alter protein structure, increased alpha helices creates more flexibility at colder temps
-Membrane structure is unsaturated fatty acids to create more fluidity

Question 34

Mesophile

Answer 34

-Grows at room temp or body temp

Question 35

Thermophile

Answer 35

-Live in hot conditions