6-1 PL Quiz Flashcards Preview

Microbiology Lab > 6-1 PL Quiz > Flashcards

Flashcards in 6-1 PL Quiz Deck (13):
1

what allows microbiologists to estimate the population density in a liquid sample

standard plate count

2

how does the standard plate count work

by plating a very dilute portion of the sample and counting the number of colonies it produces

3

the inoculum that is transferred to the plate contains a ________ _______ of the original sample

known proportion

4

what is the inoculum a product of

serial dilution

5

tubes containing a known volume of sterile diluent (water, saline, or buffer)

dilution blanks

6

what is serial dilution

a series of controlled transfers down a line of dilution blanks

7

what is the cell density usually reduced to at each step

1/10 or 1/100

8

this contains between 30 and 300 colonies

countable plate

9

what is considered statistically unreliable

a count lower than 30 colonies

10

formula used to calculate dilutions

V1D1=V2D2

11

what does CFU stand for

colony forming units

12

this is actually the number of colonies that develop on the plate

CFU

13

how do you calculate the original cell density

OCD=CFU/DxV