Lab Exam II Microbiology

Question 1

Lyses cells

Answer 1

Sodium hydroxide/Sds

Question 2

Precipitates debris

Answer 2

KOAc & detergent

Question 3

Precipitates DNA

Answer 3

90% ethanol

Question 4

Resuspend’s DNA

Answer 4

Triss EDTA buffer

Question 5

Chelates calcium and magnesium

Answer 5

EDTA

Question 6

Washes plasmid

Answer 6

70% ethanol

Question 7

Can differentiate between endogenous and DNA that is not from the cell. Spares the bacterium from infection – recognizes palindromic sequences.sticky and allow them to combine with complementary single-stranded DNA. Add last.

Answer 7

Restriction endonucleases

Question 8

nicks are annealed by…

Answer 8

DNA ligase

Question 9

Small colonies that have not taken up the plasmid (White) that form around a large colony that has released beta lactamase which degrades ampicillin and it’s vicinity.

Answer 9

Satellite colonies

Question 10

Degrades ampicillin

Answer 10

Beta lactamase

Question 11

Helps us digest carbohydrates and synthesize certain vitamins. We provide E. coli with a nice warm place to live with food. It is also protected from viruses and competition with other bacteria.

Answer 11

E. coli

Question 12

Is inhibiting the growth of one type of organism while permitting the growth of another as with an antibiotic.

Answer 12

Selection

Question 13

When you are making a distinction between different organisms such as in a blue white screening.

Answer 13

Screen

Question 14

Use reverse transcriptase to synthesize cDNA from post transcriptionally modified mRNA. The cDNA can be correctly translated in a prokaryotic cell.

Answer 14

How would you find a gene?

Question 15

Extra chromosomal DNA commonly used as cloning vector. Origin of replication, selectable marker, cloning site into which the gene can be inserted.

Answer 15

Plasmid

Question 16

Isolate DNA. Cleve DNA with restriction endonucleases and splice into a vector. Transform cells. Use selections and screens to elucidate which clones have taken up plasmid. Replica plating. Use of a primer will help you elucidate the clone expressing The gene of interest.

Answer 16

Making a gene library

Question 17

Cleves media having x-gal so bacteria producing the enzyme turn blue.
There must be a recognition sequence in the beta-galactosidase Jean so that a gene of interest may be inserted and interrupt the beta galactosidase gene. Transformants will be white. Plate on antibiotic/X gal media.

Answer 17

Beta galactosidase

Question 18

Bioxidation in which molecular oxygen can serve as the final electron acceptor.

Answer 18

Aerobic

Question 19

Bioxidation in which organic ions other than oxygen such as nitrate or sulfate can serve as the final electron acceptor.

Answer 19

Anaerobic

Question 20

Biooxidative process not requiring oxygen in which an organic substance serves as the final electron acceptor (lactic acid or alcohol fermentation. Yellow/yellow with gas)

Answer 20

Fermentation

Question 21

Alkaline slant (red) and acid butt (yellow) with or without gas production breaks in auger butt.

Answer 21

Triple sugar iron test. Fermentation of glucose.

Question 22

Acid slant yellow and acid butt (yellow) with or without gas production.

Answer 22

Triple sugar iron test. Lactose and or sucrose fermentation.

Question 23

Alkaline slant (red) and alkaline butt (red) or no change (orange/red) butt

Answer 23

Triple sugar iron test. No carbohydrate fermentation has occurred. Peptones are catabolized resulting in an alkaline pH due to the production of ammonia.

Question 24

Medium has sodium thiosulfate and Ferris sulfate to produce blackening.

Answer 24

Triple sugar iron test. hydrogen sulfide production.

Question 25

Positive result produces a cherry red reagent layer.

Answer 25

Indole production test

Question 26

Glucose fermentation reaction with methyl red PH reagent. Positive test is red. Negative test is yellow.

Answer 26

Methyl red test

Question 27

Glucose fermentation. Red layer is a positive test.

Answer 27

Voges-proskauer test

Question 28

Positive tube shows growth on slanted surface

Answer 28

Citrate utilization test

Question 29

Prevents transpeptideation resulting in a weakened peptidoglycan

Answer 29

Penicillin

Question 30

Has an affinity for bacterial ribosomes causing missreading of codons in mRNA interfering with protein synthesis.

Answer 30

Streptomycin

Question 31

Has an affinity for bacterial ribosomes preventing peptide bond formation between amino acids during protein synthesis.

Answer 31

Chloramphenicol

Question 32

Have an affinity for bacterial ribosomes prevent hydrogen bonding between the anti-codon on the transfer RNA amino acid complex and the codon on messenger RNA during protein synthesis.

Answer 32

Tetracyclines

Question 33

Inhibits cell wall synthesis

Answer 33

Bactracin

Question 34

Distraction of cell membrane

Answer 34

Polymyxin

Question 35

Inhibits RNA synthesis

Answer 35

Rifampin

Question 36

Inhibits DNA synthesis

Answer 36

Quinolone