quizzes 5-8

Question 1

agarose gel in class separates what?

Answer 1

separates DNA by size

Question 2

What is the difference between an auxotrophs and protoroph?

Answer 2

a prototroph has all the necessary proteins for biosynthesis, an auxotroph is protein deficient and does not have everything it needs

Question 3

T or F: a bacteriophage can infect and lyse a living but non replicating cell

Answer 3

false

Question 4

actinomycetes are identified by their

Answer 4

white circular appearance with bullseye

Question 5

distinguishing azotobacter from azomonas?

Answer 5

azotobacter is urease positive and forms cysts

Question 6

Which of the following method is a DNA transfer with direct contact with another microbe

Answer 6

conjugation and transduction

Question 7

calculating innoculum concentration for phage

Answer 7

pfu on plate*mL= pfu/ml

Question 8

A microbial composition changing overtime is…

Answer 8

ecological succession

Question 9

What is the pure DNA ratio?

Answer 9

1.8-1.9

Question 10

What is the difference between acinetobacter and pseudomonas?

Answer 10

pseudomonads are motile and oxidase negative

Question 11

What enzyme do propionic bacteria use to protect them from oxygen?

Answer 11

catalase

Question 12

What is the difference between aerotolerant and aeroduric?

Answer 12

aerotolerant can grow in the presence of oxygen whereas aeroduric can survive exposure to oxygen bu cannot grow in its presence

Question 13

What does eosin EMB plates do?

Answer 13

select against gram negative cocci, select against gram positive cocci, pH indicator for fermentation

Question 14

Why do we see grow in minimal casamino broth but not in minimal casein broth?

Answer 14

Growth in casamino acids because the casein is already hydrolyzed

Question 15

Why did we innoculate microscope slides with agar in order to observe aerial hyphae?

Answer 15

We use sporephore formation as a diagnostic test , see the aerial hyphae and spores