Practice Quiz Unit 3

Question 1

Peptidoglycan

Answer 1

Both gram+ and gram-.

Located in cell wall. Gram+ cells have very thick cell wall due to peptidoglycan.

Question 2

Teichoic Acids

Answer 2

Gram+.

Attaches cell wall to membrane.

Question 3

Lipopolysacharride (LPS)

Answer 3

Gram-.

Located in outer membrane.

Question 4

Outer Memrane

Answer 4

Gram-

Question 5

Periplasmic Space

Answer 5

Gram-.

Located between two membranes.

Question 6

Porin Proteins

Answer 6

Gram-.

Located in outer membrane and form transmembrane channels that allow passage of hydrophilic molecules.

Question 7

Lipid A

Answer 7

Gram-.
Toxic portion of lipopolysaccharide.
Component of out membrane.

Question 8

O Antigen

Answer 8

Polysaccharide antigen located in lipopolysaccharide.

Question 9

H Antigen

Answer 9

Flagellar antigen.

Question 10

Beta Lactam Antibiotics

Answer 10

More effective in cells during logarithmic growth phase. Targets newly forming peptidoglycan

Question 11

Quinolone

Answer 11

Targets DNA gyrase and DNA topoisomerase (?).

Question 12

Coagulase

Answer 12

Promotes deposition of fibrin and walls off S. aureus.

Question 13

Infection

Answer 13

Microbe enters into relationship with host.

Question 14

Pili

Answer 14

Bacterial structure most commonly involved in mediating adherence of bacteria to human cells.

Question 15

Enterococcus Spp.

Answer 15

Gram+. Forms chains.

Mostly likely to be found as part of normal bowel flora.

Question 16

Clostridium difficile

Answer 16

Associated with antibiotic use due to antibiotic resistance. Causes diarrhea.
Part of normal flora w/o causing disease.
GI disease related to toxin production.

Question 17

McConkey Agar

Answer 17

Allows growth of gram- bacteria only.

Question 18

Lactose Fermenting Bacteria (when grown on McConkey agar)

Answer 18

E. coli, Klebsiella pneumoniae

Question 19

Gram Stain

Answer 19

Adheres to peptidoglycan, which makes thick cell wall in gram+ cells.

Question 20

Genetic Recombination

Answer 20

Allows bacteria to express different antigenic forms of pili.

Question 21

Bacteriophage Converion (Lysogenic Conversion)

Answer 21

Mechanism of phage mediated transfer. Process where bacteria incorporates phage DNA that confers a new phenotypic trait into own genome. Allows diptheriae to express diptheria toxin.

Question 22

Klebsiella pneumoniae

Answer 22

gram- rod

Question 23

Glycocalyx

Answer 23

Virulence factor most associated with Staph epidermis

Question 24

Transformation

Answer 24

Naked strands of DNA are incorporated into bacterial genome. Possible in both gram+ and gram- bacteria.

Question 25

Generalized Transduction

Answer 25

Mechanism of phage-mediated transfer. Gene transfer mediated by a bacteriophage, where any segment of donor phage (bacterial?) genome is passed into another cell.

Question 26

Bacterial Conjugation

Answer 26

Form of genetic transfer that is dependent upon contact between donor and recipient cells. Usually mediated by certain types of bacterial plasmids.

Question 27

Virulence Genes

Answer 27

Are often expressed only under conditions of low iron. | May be obtained in complex transposons, during bacteriophage conversion, or in the acquisition of plasmids.

Question 28

Lytic Infection

Answer 28

Phage multiplication leading to host cell lysis.

Question 29

Transposition

Answer 29

DNA sequence that can change its position within the genome.

Question 30

prophage

Answer 30

Consists of phage DNA which is linearly inserted into host cell genomes where it becomes passively replicated as part of host bacterial chromosome.

Question 31

Insertion Sequence Transposon

Answer 31

Encode transposase. Inactivate genes into which they are transposed or turn on expression of adjacent genes.

Question 32

Complex Transposons

Answer 32

Similar to regular transposons but carry additional genes such as those encoding antibiotic resistance, toxins, or other virulence factors.

Question 33

Endotoxin

Answer 33

LPS from cell walls of gram- bacteria

Question 34

Exotoxin

Answer 34

Toxin secreted by bacteria.

Question 35

Enterotoxin

Answer 35

Exotoxin that acts in GI system.