Quiz 6

Question 1

Binary Fission Outline

Answer 1

1. Division Prep - enlarge cell wall, membrane, volume
2. Septum grows, chromosomes move, cytoplasmic distribution
3. Cell membrane patches itself

Question 2

ParM

Answer 2

elongates, pushing each plasmid to opposite poles of the dividing cell

Question 3

FtsZ

Answer 3

Z ring formation

Question 4

Z ring

Answer 4

serves as a scaffold for the division proteins that divide the cell in two

Question 5

NAG + UTP

Answer 5

UDP-NAG

Question 6

UDP-NAG + PEP

Answer 6

UDP-NAM

Question 7

Cytoplasmic Stage

Answer 7

Building the NAM and NAG precursors

Question 8

Membrane Stage

Answer 8

movement of NAM and NAG across the membrane by bactoprenol

Question 9

Peptidoglycan Synthase

Answer 9

Flips this bactoprenol-sugar complex to the other side of the membrane

Question 10

Extracellular Stage

Answer 10

Cross-linking by the transpeptidase

Question 11

Vancomycin

Answer 11

another cell wall inhibitor that attaches to the last two amino acids

Question 12

Biofilm Growth

Answer 12

1. Substratum pre-conditioning by ambient molecules
2. Cell deposition
3. Cell absorption
4. Desorption
5. Cell-to-cell signaling
6. Convective and diffusive transport of O2
7. Replication/growth
8. Secretion of polysaccharides
9. Detachment, erosion, sloughing

Question 13

Biofilm Concerns

Answer 13

Antibiotic resistance, gene transfer, development of super bacteria, persister microbes

Question 14

Quorum Sensing

Answer 14

Method of bacterial communication, bacteria can sense wether there is quorum (high cell density) and recruit additional microbes to the site

Question 15

Microbial Population Growth

Answer 15

Lag Phase -> Exponential Phase -> Stationary Phase -> Death Phase

Question 16

Genomic Cell Counting

Answer 16

Quantitative PCR, 16S ribosomal RNA sequencing

Question 17

Culture-based Measures

Answer 17

Cell counter, colony forming units

Question 18

Growth rate constant

Answer 18

K = n/t

Question 19

Osmophiles

Answer 19

microbes that are adapted to hypertonic environments, require high sugar concentrations

Question 20

Compatible Solutes

Answer 20

inorganic and organic molecules with neutral charge that microbes obtain to cope with osmotic stress

Question 21

Psychrophiles

Answer 21

readily isolated from the arctic and the ocean, max growth 20, optimum 15, min 0

Question 22

Obligate Aerobe

Answer 22

Must use O2 as final e- acceptor

Question 23

Facultative Anaerobe

Answer 23

Can use O2 as final e- acceptor

Question 24

Aerotolerant Anaerobes

Answer 24

Cannot use O2, but no poisonous

Question 25

Obligate Anaerobes

Answer 25

Cannot use O2, poisonous

Question 26

Microaerophiles

Answer 26

Use O2 at low concentrations

Question 27

Piezophilic

Answer 27

optimal growth as high pressures, change their membrane lipids in response to pressure

Question 28

Barotolerant

Answer 28

pressure adversely affects them but not as much as non-tolerant microbes

Question 29

Sterilization

Answer 29

process by which all living cells, spores, and a cellular agents are destroyed or removed from an object or habitat

Question 30

Disinfection

Answer 30

killing, inhibition, or removal of microorganisms that might cause disease

Question 31

Sanitation

Answer 31

microbial population reduced to levels that are considered safe by public health standards

Question 32

Antisepsis

Answer 32

destruction or inhibition of microorganisms on living tissue

Question 33

Pasteurization

Answer 33

controlled heating for heat-sensitive substances, does not sterilize, but does sanitize, lowers total microbial load and kills pathogens present

Question 34

Boiling

Answer 34

destroyers vegetative cells

Question 35

Autoclaving

Answer 35

steam sterilization

Question 36

Air Filtration

Answer 36

method to reduce microbial populations in the lab

Question 37

Phenolic Compounds

Answer 37

many denature proteins, disrupt cell membranes, antimicrobial (lysol, tannins)

Question 38

Alcohols

Answer 38

denature proteins and dissolve membrane lipids

Question 39

Halogens

Answer 39

fluoride, chlorine, iodine, form salt like compounds

Question 40

Aldehydes

Answer 40

cross-link with microbial proteins and amino groups in peptidoglycan, highly reactive, disrupt protein structure, peptidoglycan function

Question 41

Bactoprenol

Answer 41

integral membrane protein transports NAG/NAM outside the cell

Question 42

AHL release

Answer 42

low density

Question 43

AHL diffuse in

Answer 43

high density

Question 44

Paul Ehrlich

Answer 44

father of chemotherapy, arsphenamine, kills syphilis