i used 0.1 mL to inoculate the plate,the question is to calculate population den

ID: 275490 • Letter: I

Question

i used 0.1 mL to inoculate the plate,the question is to calculate population density in 10^-1,10^-2,10^-3,10^-4.10^-5.10^6.all the number of the colony in the picture

x, x2 1 a-ay . A- ??1 : . 1 a-o-LIN° mal No Spac.. Heading 1 Heading 2 Title Font Paragraph Styles Table 3: Experiment 1 Growth Results Plate 10 102 1010 10 10 Classification (TNTC, TFTC, Countable) CFU/plate (actual count of colony numbers if appropriate) Calculated Population Density (CFU original/ml) TNTC TNTC TNTC TNTC TNTC TNTC 48 30 32 23 9 1. Define CFU is colony forming unit. It is a unit that is used in determination of the number of viable bacteria in a sample.

Explanation / Answer

TNTC – Too numerous to count - If the CFUs are more than 300, those are classified as TNTC

Countable - If the CFUs are between 30-300, those are classified as countable

TFTC – Too few to count - If the CFUs are less than 30 those are classified as countable

The factor to convert 0.1 ml to 1 ml is 10, so, to predict the no of approximate CFU /ml, the formula is = The no of CFUS from 0.1 ml X Factor i.e. 10.

For example no. of colonies from 10^-1 dilution = 48X10 = 480.

If you find any difficulty leave me a comment.

Plate

10^-1

10^-2

10^-3

10^-4

10^-5

10^-6

Classification

Countable

TFTC

CFU/PLATE (0.1 ml)

No. of colonies per ml

480

300

320

230

110

Dilution factor

100

1000

10000

100000

1000000